chronic PHC 331 slides (1).pdf

Chapter 2: Methods in Chronic Disease Epidemiology PHC 331: Chronic Disease Epidemiology and Prevention 1 Definition of Epidemiology The science of public health Greek epi (upon), demos (people), logos (study) Now includes injury, disability, risk factors, quality of lif...

Chapter 2: Methods in Chronic Disease Epidemiology PHC 331: Chronic Disease Epidemiology and Prevention 1 Definition of Epidemiology The science of public health Greek epi (upon), demos (people), logos (study) Now includes injury, disability, risk factors, quality of life, and, traditionally, disease Center for Disease Control (CDC) defines epidemiology as “the study of the distribution and determinants of health-related states in specified populations, and the application of this study to the control of health problems.” PHC 331: Chronic Disease Epidemiology and Prevention 2 Definition of Epidemiology, contd. Based on the CDC’s definition, a breakdown of the terms: Study – quantitative, statistic- and research-based Distribution – characterized through people and how health events happen in populations Determinants – causes, factors, implemented in analytical epidemiology Health-related states – not just diseases, a spectrum of ailments Populations – groups of people, not just individuals Control – implement decision-making processes to prevent health issues PHC 331: Chronic Disease Epidemiology and Prevention 3 The Chronic Disease Continuum Diseases of known microorganisms (AIDS, flu, etc.) focus the study of epidemiologists Likewise, injuries are acute, with often immediate health consequences (car accidents, falling, etc.) However, many chronic diseases originate early in life through unhealthy behaviors, which, in turn, increase the risk in later life to develop these diseases This (detailed below) is called the chronic disease continuum Descriptive Epidemiology, Analytic Epidemiology, Intervention/Evaluative Research Developmental, Health risk behaviors Adapted from social, environmental, Chronic conditions Chronic diseases and other factors Remington et al. genetic determinants (2010) PHC 331: Chronic Disease Epidemiology and Prevention 4 The Chronic Disease Continuum, contd. An important question is at what point are epidemiologist trying to “control” a chronic disease? At which stage of the continuum? Controlling has become not only achieving lower mortality rates, but also lowering detrimental effects of the disease Both of these factors are used to describe the natural history of a given disease PHC 331: Chronic Disease Epidemiology and Prevention 5 Descriptive Epidemiology Uses readily available data to examine a disease and who it affects in populations by time, place, or person Assesses burden, at risk groups, trends Public tends to focus on incurable diseases or environmental diseases, instead of chronic diseases that fall on the continuum. PHC 331: Chronic Disease Epidemiology and Prevention 6 The Burden of Disease Frequently, the count of affected individuals is seen as the fundamental measure Implemented when analyzing the need for healthcare to aide in lessening the burden Count is a simple way to present this burden to the general public, but it is dependent on the population size Other measures can be used by epidemiologists to highlight different elements of the disease PHC 331: Chronic Disease Epidemiology and Prevention 7 Calculating Rates Rates are used to compare populations – incidence and prevalence Incidence rate – new cases over period ÷ person-years Person-years = persons × period monitored Cumulative incidence – probability of developing a disease, ranging from 0 to 1 Prevalence – another proportion, this one measured at a point in time instead of a period Less valuable than incidence in identifying causes PHC 331: Chronic Disease Epidemiology and Prevention 8 Comparing Rates Compared using risk ratios/relative risks Rate ratio – incidence rate of one group compared to another Rate difference – subtracting the rates from one another Calculates how much risk is different given certain variables in the study Rates also used to aim program targeting goals At-risk subgroups are found within populations Can assist healthcare professionals in joint interventions PHC 331: Chronic Disease Epidemiology and Prevention 9  Difference between rat ratio and rate difference Mortality Rate Disease Smokers (a) Nonsmokers (b) Ratio (a/b) Difference(a-b) Lung cancer 131 11 11.9 120 Coronary heart 275 153 1.8 122 disease PHC 331: Chronic Disease Epidemiology and Prevention 10 Study Designs Randomized controlled trials (RCTs) – the most thorough and scientific study Subjects assigned to prevention or non-prevention Disease and death-rates monitored and observed over time Often impractical/impossible Need comparison groups for analysis Comparisons between (least effective) national data and (most effective) concurrent collection vary in appropriateness PHC 331: Chronic Disease Epidemiology and Prevention 11  Study Designs in Chronic Disease Epidemiology Experimental Studies 1- RCT :-Randomized controlled trials (RCTs) are considered the most scientifically rigorous type of epidemiological study. In an RCT, subjects are randomly assigned to either receive or not receive a preventive or therapeutic procedure, such as a clinical smoking cessation intervention or a new drug. The disease course or mortality patterns are then observed over time to assess the effectiveness of the preventive or therapeutic procedure (Remington et al, 2010) PHC 331: Chronic Disease Epidemiology and Prevention 12  Advantages of RCT Comparison groups vary in their appropriateness for disease intervention studies. Least convincing are comparisons with national data or populations in other studies. Subjects assigned to prevention or non-prevention Disease and death-rates monitored and observed over time Often impractical/impossible Need comparison groups for analysis PHC 331: Chronic Disease Epidemiology and Prevention 13 Study Designs, contd. Historical or retroactive studies can also be a viable option, if the correct records are available Downsides include that no incidence rates or cumulative incidence can be gathered Upsides include that, in certain cases, information was found that affected risks which could be modified and benefit a population in the future Adapted from Remington et al. (2010) PHC 331: Chronic Disease Epidemiology and Prevention 14 Observational Studies Since RCTs can be unethical, epidemiologists need to observe without intervention Based on doctor recommendations Prospective cohort – exposures not randomly assigned, but first identified Active and intense measurements can be made PHC 331: Chronic Disease Epidemiology and Prevention 15 Strengths/Limitations of Study Designs Study Type Strengths Limitations Experimental studies Randomized clinical trial *Controls randomly assigned *High cost *Impractical long-term *Impractical exposures Randomized community trial *Population-wide scope *Very expensive *Multicomponent effectiveness *Small number of study groups Quasi-experimental study *Real-world policy/program intervention *Potential bias *Multiple comparison groups *Lack of control – confounders Observational studies Prospective cohort *Measure risk before disease occurs *Expensive *Multiple outcomes *Large number of subjects required *Yields incidence rates/relative risks *Lengthy follow-ups *Hard to control exposure factors Case-control *Rare diseases *Possible risk-factor bias *Inexpensive *Possible bias in control group selection *Quick results *Identified might not represent population Adapted from Remington et al. (2010) PHC 331: Chronic Disease Epidemiology and Prevention 16 Assessing Valid Study Results Most chronic disease studies are from observational studying Therefore, errors are present in a number of different ways: Measurement, selection of subjects, bias, etc. Experts are needed to quantify uncertainty in research methods and decide quality studies Confounding and bias are important types of error in epidemiological studies PHC 331: Chronic Disease Epidemiology and Prevention 17 Confounding “The influence of an exposure of interest is mixed with the effect of another” (Remington et al. 2010) In RCT, confounders can be equally distributed among each study group In observational studies, confounders have to be measured and adjusted As long as confounders are measurable and adjusted, then no need for concern However, some confounders are difficult to measure or unknown PHC 331: Chronic Disease Epidemiology and Prevention 18 Selection/Information Bias Faulty sampling methods or refusal to participate leads to samples with higher or lower measurement risk Poorly arranged control groups are major threats to accuracy Phone samples introduce bias when families without landlines are not taken into account Classification errors also present a potential bias Also known as information bias PHC 331: Chronic Disease Epidemiology and Prevention 19 Prevention through Intervention Attributable Risk How much burden is lessened is exposure is eliminated Relative risk - 1 ÷ relative risk Population Attributable Risk How common the exposure is Rate (total pop.) - rate (unexposed) ÷ rate (total pop.) Also Pe (relative risk - 1) ÷ 1 + Pe (relative risk - 1) Where Pe proportion of population exposure PHC 331: Chronic Disease Epidemiology and Prevention 20 Single vs. Series Often, critical analyses will lead to “important” or “groundbreaking” new information, but this must be taken lightly One study is never sufficient to answer all or even one question about a chronic disease. Validity must be measured through repetition and variety or intervention PHC 331: Chronic Disease Epidemiology and Prevention 21 Systematic Reviews, Meta-analysis, Expert Panels Systematic reviews Researchers consolidate information using comprehensive methods to assess relevant science behind a single health issue Increasingly, meta-analysis is used in these systematic reviews Meta-analysis Identify relevant studies, inclusion/exclusion criteria, data abstraction, heterogeneity across statistical analysis PHC 331: Chronic Disease Epidemiology and Prevention 22  Risk Assessment/Expert panels An approach to looking at risks posed by adverse exposures like pollutants A “bridge” between the scientific community and those who create policies and protocol Four steps to proper risk assessment: Hazard identification, risk characterization, exposure assessment and risk estimation Expert panels used to assess validity of epidemiological studies through peer review PHC 331: Chronic Disease Epidemiology and Prevention 23 Key Concepts Incidence rate – New events in a specified period / persons exposed to risk within period Relative risk – Risk of death or disease in population exposed to risk / risk of death or diseased in unexposed population Population attributable risk – Rate of disease in population attributed to risk factor / total rate of disease PHC 331: Chronic Disease Epidemiology and Prevention 24  Chapter 3: Intervention Methods for Chronic Disease Control PHC 331: Chronic Disease Epidemiology and Prevention 1 Behavioral Determinants Behavior changes in individuals can often prevent many chronic diseases CDC estimates that 80% of heart disease, type II diabetes and 40% of cancer would be eliminated if poor diet, inactivity and smoking were also eliminated Obesity is now seen more frequently among both adults and children PHC 331: Chronic Disease Epidemiology and Prevention 2 Healthcare Determinants The high cost of treating chronic diseases is another reason they are increasing Secondary prevention can find many diseases earlier when they are cheaper to treat and more beneficial to lifestyle change, and also lead to fewer visits in later years (which will lower health costs) Lack of incentives for prevention services in US healthcare system PHC 331: Chronic Disease Epidemiology and Prevention 3 Environmental Determinants Features like sidewalks, parks, bike trails, community pools all encourage healthier choices Households with multiple televisions and computers also promote a less-active culture which affects the amount of exercise being done Nutritional choices also under consideration in built environments – menus, work cafeterias, highlight lower costs for less nutritional foods PHC 331: Chronic Disease Epidemiology and Prevention 4 Social Determinants Population health is emerging as just as important as individual health Policymakers are quick to blame individual choices for chronic illness, when, in reality, there are an amplitude of environmental, cultural and economic factors at play Social determinants are often a large result of health disparities PHC 331: Chronic Disease Epidemiology and Prevention 5 Levels of Intervention Victim-blaming fails to account environmental and social – ecological approach acknowledges that we live in a world full of interactions Intrapersonal factors Interpersonal factors Organizational factors Community factors Policy factors PHC 331: Chronic Disease Epidemiology and Prevention 6 Health Belief Model Early attempt to use theory to study preventive behaviors If subject perceives moderate severity and susceptibility, then choose preventative action Often criticized and used to explain how people rarely adopt preventative behaviors Content of Health Belief Model:- Perceived Suscessiability Perceived severity Perceived benefits Perceived barrier Cuss to action self- efficacy PHC 331: Chronic Disease Epidemiology and Prevention 7 Perceived susceptibility - This refers to a person's subjective perception of the risk of acquiring an illness or disease. There is wide variation in a person's feelings of personal vulnerability to an illness or disease. Perceived severity - This refers to a person's feelings on the seriousness of contracting an illness or disease (or leaving the illness or disease untreated). There is wide variation in a person's feelings of severity, and often a person considers the medical consequences (e.g., death, disability) and social consequences (e.g., family life, social relationships) when evaluating the severity. Perceived benefits - This refers to a person's perception of the effectiveness of various actions available to reduce the threat of illness or disease (or to cure illness or disease). The course of action a person takes in preventing (or curing) illness or disease relies on consideration and evaluation of both perceived susceptibility and perceived benefit, such that the person would accept the recommended health action if it was perceived as beneficial. PHC 331: Chronic Disease Epidemiology and Prevention 8 Perceived barriers - This refers to a person's feelings on the obstacles to performing a recommended health action. There is wide variation in a person's feelings of barriers, or impediments, which lead to a cost/benefit analysis. The person weighs the effectiveness of the actions against the perceptions that it may be expensive, dangerous (e.g., side effects), unpleasant (e.g., painful), time-consuming, or inconvenient. Cue to action - This is the stimulus needed to trigger the decision-making process to accept a recommended health action. These cues can be internal (e.g., chest pains, wheezing, etc.) or external (e.g., advice from others, illness of family member, newspaper article, etc.). Self-efficacy - This refers to the level of a person's confidence in his or her ability to successfully perform a behavior. This construct was added to the model most recently in mid-1980. Self-efficacy is a construct in many behavioral theories as it directly relates to whether a person performs the desired behavior. PHC 331: Chronic Disease Epidemiology and Prevention 9 Health Belief Model PHC 331: Chronic Disease Epidemiology and Prevention 10 Trans theoretical Model Also known as Stages of Change Model Not everyone at the same stage to drastically change health behavior, so each plan fits to different characteristics Series of stages, from pre-contemplation (no change) to termination (problem no longer acceptable) or relapse (retroactively choosing less healthy behavior) PHC 331: Chronic Disease Epidemiology and Prevention 11 Theory of Planned Behavior Individuals are fueled by behavioral intentions An attitude of a positive behavior is “is the sum of all the positive feelings…or negative feelings…about performing the behavior” (Remington et al. 2010). Places normative beliefs on people’s perceptions and readiness to change PHC 331: Chronic Disease Epidemiology and Prevention 12 Health Locus of Control Expectancy is important when considering control – where, who, what is/are responsible? If there is belief that a plan of action will result in an outcome, a person is more likely to pursue that option Control moves from internal (self) to external (higher powers, luck, fate, etc.) Those who lean toward external control are more likely reached through policy changes PHC 331: Chronic Disease Epidemiology and Prevention 13 Social Cognitive Theory Addresses dynamic of society that influence health and methods for behavioral change Triadic, dynamic, reciprocal models Emphasis placed on highlighting capability and self-confidence Self-efficacy through mastery of task Applicable to wide variety of populations PHC 331: Chronic Disease Epidemiology and Prevention 14 Family-Based Interventions Monopolizes on existing string of social network (family) to implement support Family trained to assist in weight loss program, for example “Family Matters” program to prevent youth smoking and alcoholism PHC 331: Chronic Disease Epidemiology and Prevention 15 Friends and Social Networks Mentor programs, buddy systems, self-help groups Creating a new social network with the sole purpose of intervening Especially important in adolescent interventions PHC 331: Chronic Disease Epidemiology and Prevention 16 Social Support and Social Networks Social support Emotional support Instrumental support Informational support Appraisal support Either strengthening existing networks or creating new ones to assist in the problem-solving process PHC 331: Chronic Disease Epidemiology and Prevention 17 Natural Helpers A member of a social network who gains trust and respect through his or her abilities to offer support and guidance These strategies are seen frequently in urban and rural settings Natural helpers are either found in a community organically, or is given specialized training (this is known as a lay health advisor) PHC 331: Chronic Disease Epidemiology and Prevention 18 Health Care System and Clinical Services Effective in providing screening/follow-ups However, often underutilized in primary prevention (see Slide 3) Brief interventions are low cost alternative to high cost visits Short, private, non-confrontational, 5-60 minute meeting with counseling and informative education Can be leveraged depending on a person’s aptitude and readiness for change PHC 331: Chronic Disease Epidemiology and Prevention 19 Schools Youth are a spirited, receptive audience for prevention messages Establishing healthier habits at an earlier age is essential in stopping or slowing chronic illness PHC 331: Chronic Disease Epidemiology and Prevention 20 Work Sites US adult population spends half or more of the day at work, so it becomes a useful tool in dispensing knowledge about prevention education Leaders are understanding that chronic diseases are costing more and more (employee absence, insurance costs, etc.) and are mediating this through health knowledge at the workplace. Results: Improved productivity Reduced absences Reduced health risks/health care costs Improved company image PHC 331: Chronic Disease Epidemiology and Prevention 21 Examples of Community-Level Health Planning Approaches Selected based on priorities of population in question Priority population partners – participatory, collaborative, local, empowering, research and action blend Community coalitions Media advocacy – seen today in suicide prevention, and lead poisoning, to name a few PHC 331: Chronic Disease Epidemiology and Prevention 22 Community-Level Health Planning Process planning Plan with people Plan with data Institutionalization Priorities Short- and long-term outcomes Evaluation PHC 331: Chronic Disease Epidemiology and Prevention 23 Community-Based Prevention Marketing Mobilizing the community Developing a community profile Selection behavior/audiences Formative research Strategy development Program development Program implementation Tracking PHC 331: Chronic Disease Epidemiology and Prevention 24 Chapter 4: Chronic Disease Surveillance PHC 331: Chronic Disease Epidemiology and Prevention 1 Conceptual Model of Health Surveillance Adapted from Remington et al. (2010) Define the Problem Data Collection Find Programs Information Dissemination Data Analysis that Work Data Evaluate Interpretation the Effect Program Process Epidemiologic Process PHC 331: Chronic Disease Epidemiology and Prevention 2 Notifiable Disease Systems Council of State and Territorial Epidemiologists modifies this list each year Includes primarily infectious diseases, but also contains some noncommunicable diseases, as well In 1996, CSTE included smoking, the first behavior on the list 2004 list contains 92 disease systems Chronic Disease Indicators website includes definitions and data of each in the United States PHC 331: Chronic Disease Epidemiology and Prevention 3 Vital Statistics Collected information from birth and death An initial cornerstone of surveillance since the mid-19th century and perhaps earlier Death certificates are used to list immediate causes of death and a string of events that caused death (underlying cause) Limitation – incomplete certificate, lack of clinical history PHC 331: Chronic Disease Epidemiology and Prevention 4 Sentinel Surveillance One symptom or a string of symptoms, disease, disability, etc. Effectiveness yet to be proven by research Could potentially identify outbreaks or bioterrorism PHC 331: Chronic Disease Epidemiology and Prevention 5 Chronic Disease Registries Used in monitoring trends Usually mandated in state laws Most common disease registries – cancer Hospital-based or population-based registries PHC 331: Chronic Disease Epidemiology and Prevention 6 Health Surveys Implemented when collecting information from self- reported health practices (general pop.) CDC established a phone-based surveillance system of questionnaires Some surveys go beyond questionnaires and access physical exams and samples Collected at mobile examination centers PHC 331: Chronic Disease Epidemiology and Prevention 7 Administrative Data Collection Systems Primarily hospital discharge data Used to locate hospitalization patterns of chronic diseases Limitations – incomplete records, unreliable imputation of data, missing variables, measurement errors, only focus on hospital setting, not outpatient care PHC 331: Chronic Disease Epidemiology and Prevention 8 Census Data Each 10 years, the United States government censuses the entire population – collects detailed information on individual and household Limitations – census does not include everyone; inevitably some are missed Minority racial/ethnic groups Geographic areas PHC 331: Chronic Disease Epidemiology and Prevention 9 Person Analyses Charts the variety of a disease given their personal attributions Race, age, gender, etc. Realizing differences in these factors helps design effective and group-specific prevention or control programs PHC 331: Chronic Disease Epidemiology and Prevention 10 Place Analyses Charts a disease that occurs in one geographic region against another region Typically found in situations when a city or county is compared to state or country Needs to understand and interpret age structure between areas by age- standardization Cluster analysis – in acute geographic areas – monitored to avoid health risks specific to a very small area (neighborhoods, communities, suburbs, etc.) PHC 331: Chronic Disease Epidemiology and Prevention 11 Time Analyses Charts trends that appear over time Used to detect outbreaks, transmission patterns, intervention strategies Temporal trends, regional analysis Interventions based on variables specific to a certain time in a certain era PHC 331: Chronic Disease Epidemiology and Prevention 12 Data Dissemination Data dissemination is the final step in disease monitoring Often composed in documents with technical language, with little linkage to public health promotion Epidemiologists asked to disseminate the information collected into health department reports Five steps in data analysis: Establish the message, set an objective, define the audience, select the channel, evaluate the impact PHC 331: Chronic Disease Epidemiology and Prevention 13 Message Arguably the most important element of data presentations The role of the epidemiologist is to convey a clear message, one that is worthwhile and somewhat easy to understand “Less is more” approach Main points must be easy to understand PHC 331: Chronic Disease Epidemiology and Prevention 14 Objective Goal of epidemiologist is to establish an objective for a piece of writing Goals vary – sometimes there is no goal, simply that there is something to be reported, other times objective is for general public education Sometimes the ideal objective is public action PHC 331: Chronic Disease Epidemiology and Prevention 15 Audience Target audience varies, but has traditionally been both local health departments and health care providers These agencies are charged with implementing any strategies for managing disease control Today, a broader spectrum of target audience exists – from policymakers and legislators, or to the general public, advocacy agencies to promote their efforts PHC 331: Chronic Disease Epidemiology and Prevention 16 Channel The method or medium that an epidemiologist “channels” his or her work Journals, paper/electronic mail, radio/television, blogs, print/digital media, etc. Frequently mailed to healthcare facilities Sometimes a press release is required Selective channeling aides research in reaching target audience PHC 331: Chronic Disease Epidemiology and Prevention 17 Impact Final step is evaluating how the information was distributed using the previous four methods This can be measured in various ways – number of items distributed, where and how, readership, coverage, hits on a webpage, web searches The success of the previous methods outline the impact that a particular public health campaign may have PHC 331: Chronic Disease Epidemiology and Prevention 18 Chapter 5: Tobacco Use PHC 331: Chronic Disease Epidemiology and Prevention 1 Significance According to WHO,2017: The tobacco epidemic is one of the biggest public health threats the world has ever faced, killing more than 8 million people a year around the world. More than 7 million of those deaths are the result of direct tobacco use while around 1.2 million are the result of non-smokers being exposed to second-hand smoke. Smoking harms every organ of the body, with diseases including Cardiovascular diseases Cancers – lip, mouth, esophagus, lung, kidney, etc. Respiratory problems Reproductive disorders SIDS, cataracts, slow wound healing Low bone density PHC 331: Chronic Disease Epidemiology and Prevention 2 Cardiovascular Disease Smoking a major risk factor in developing congenital heart disease Ability of blood to delivery oxygen is reduced Secondhand smoking causes prothrombotic effects and endothelial cell dysfunctions PHC 331: Chronic Disease Epidemiology and Prevention 3 Cancer “Mainstream tobacco smoke (MS) contains nearly 5,000 chemicals…and more than 60 known carcinogens” (Remington et al. 2010) These carcinogens have been linked to tobacco- related cancers Nitrosamines/polyaromatic hydrocarbons – lung cancer N-nitrosodimethylmine – kidney tumors Nitrosamine NNK – pancreatic cancer Benzene, polonium-210, lead-210 – myeloid leukemia PHC 331: Chronic Disease Epidemiology and Prevention 4 Chronic Lung/Other Respiratory Disease When you smoke, additional biological processes like inflammation, degradation of structural proteins and oxidant stress are developed, which can cause alveolar injury Results in COPD Hypoxemia Decline in pulmonary function Reduction of tracheal mucus velocity PHC 331: Chronic Disease Epidemiology and Prevention 5 Nicotine Dependence Nicotine distribution absorbs rapidly to the brain in both oral and inhalation of tobacco – around ten seconds upon initial use Crosses blood-brain barrier and binds to receptors in brain, which releases neurotransmitters Effects dependent on rate of use, tolerance Withdrawal symptoms include irritability, frustration, increased appetite, weight gain, and generally occur within one day and maintain for ten days, though cravings for regular smokers last for years PHC 331: Chronic Disease Epidemiology and Prevention 6 High-Risk Groups In the United States, estimated 43 million smokers Higher for men (22%) than women (17%) 10% - Asians; 13% - Hispanics; 20% - African Americans; 21% - Caucasians; 36% - Native Americans and Alaska Natives (Remington et al. 2010) A 2005 study found that 51% of men and 50% of women were smokers at one time but had quit Estimated 4,000 young people smoke their first cigarette each year According to the Global Burden of Disease study more than 8 million people died prematurely as a result of smoking in 2017. PHC 331: Chronic Disease Epidemiology and Prevention 7  Number of tobacco users global by sex ( WHO,2019) The number apparently peaked in 2018 at 1093 million tobacco users. Between 2000 and 2005, the number of male tobacco users increased by 22 million; between 2005 and 2010, the increase slowed to 13 million, and slowed again to a 7 million increase between 2010 and 2015. The number of users is projected to decrease going forward from 2018, decreasing by 2 million to 1 091 million in 2020, then by another 4 million to 1 087 million in 2025, assuming countries maintain current efforts in tobacco control. PHC 331: Chronic Disease Epidemiology and Prevention 8  Global trends in prevalence of tobacco use by sex ) WHO, 2019) In 2000, around half of men aged 15 years and older were current users of some form of tobacco. By 2015, the proportion of men using tobacco had declined to 40.3%. By 2025, the rate is projected to decline to 35.1%. In 2000, around one in six women (16.7%) aged 15 years and older were current users of some form of tobacco. By 2015, the proportion of women using tobacco had declined to under one in ten (9.5%). By 2025, the rate is projected to decline to 6.7%. any form of tobacco was three times in 2000, the proportion of males using e proportion of users among women. By 2015 the rate for males was more than four times the rate for females. By 2025 the rate for males is expected to be five times the rate for females. PHC 331: Chronic Disease Epidemiology and Prevention 9 Trends in current tobacco use among people aged ≥15 years PHC 331: Chronic Disease Epidemiology and Prevention 10 Time Trends Peak cigarette sales in the United States in 1963 – steadily declining since Over time, the gap between men (historically higher rates) and women (lower) has been narrowing, but the declination rate is lowering at a comparable rate From 2002, more former smokers than current smokers PHC 331: Chronic Disease Epidemiology and Prevention 11 Modifiable Risk Factors Societal and individual factors – exposure in popular films, perception of safeness among certain brand Advertising and promotion – media sponsorship, high budget spend on advertisement from tobacco companies “Safer” tobacco – low-tar branding Access – vending machines and some sales counters selling to minors PHC 331: Chronic Disease Epidemiology and Prevention 12 Modifiable Risk Factors, contd. Social norms – societal, local, familial, peer communities all affecting smoking; when access to tobacco exists in these communities, it becomes easier to acquire Individual psychosocial factors – weaker attachment to parents, stronger attachment to peers, rebelliousness and risk-taking Continued tobacco use – the role of genetics in treatment response; the effect of advertising and “safer” products PHC 331: Chronic Disease Epidemiology and Prevention 13 Modifiable Risk Factors, contd. Inadequate understanding – underestimation of smoking-related deaths; assumption that young people will stop before potentially harmful side effects occur Adults not aware of hazards, which can be attributed to underrepresentation of anti-smoking literature and media Lower price – the lower the price, the more cigarettes and tobacco are consumed PHC 331: Chronic Disease Epidemiology and Prevention 14 Population-Attributable Risk Several recent studies have suggested the influence that risk factors play when defining tobacco use One study postulated that 33% of experimentation with tobacco among youth attributed to advertisements; Two others speculate that cinema/Hollywood glorification of tobacco leads to higher risks; A third looks at youth with nonsmoking parents smoking as a direct result of movies and popular culture PHC 331: Chronic Disease Epidemiology and Prevention 15 Prevention and Control Price Increasing the price of tobacco can help stymy sales, especially among youth Sales would have to increase across all types of tobacco to be effective Countermarketing campaigns Pointed at youth prevention, but need to be sustained to be effective Challenge social norms about tobacco use, educate youth on prevention Advertising bans Mixed evidence on effectiveness When a ban is in place, tobacco companies shift to other forms of delivery – electronic, billboards, points of sale PHC 331: Chronic Disease Epidemiology and Prevention 16 Prevention and Control, contd. Minors’ access restrictions More stringent interventions are needed to lower youth accessibility of tobacco School-based tobacco prevention programs Effective when taught alongside community interventions Emphasize tobacco-free campuses, negative health effects Eliminating secondhand smoke Eliminating smoking indoors helps, but cannot prevent complete exposure Also helps reduce cigarette consumption in general PHC 331: Chronic Disease Epidemiology and Prevention 17 Screening and Treatment Best practice in the medical field – ask about past history with tobacco use Should be acquired during every visit and thoroughly documented in a medical record Those who smoke should be screened so effective treatment can be given as needed Cotinine can be measured in blood, saliva, urine – though acquiring these levels not particularly routine in medical care, except in the case of pregnant women’s tobacco intake PHC 331: Chronic Disease Epidemiology and Prevention 18 List of Evidence-Based Interventions Comprehensive tobacco prevention and control programs: Estimated that prevention programs have added 21 years to the life expectancy between 1964 and 1992 for 1.6 million Americans California spearheaded the prevention programs, and has lower cases of lung cancer, lowest per capita consumption, and low youth smoking rate than the rest of the United States Tobacco excise taxes Increased taxation on cigarettes, though remedied by tobacco companies by coupons and other discounting strategies PHC 331: Chronic Disease Epidemiology and Prevention 19 List of Evidence-Based Interventions, contd. Countermarketing campaigns Smoke-free policies Public and private insurance coverage Minors’ access restrictions Telephone cessation quitlines Usually not enough funding to sustain Product changes PHC 331: Chronic Disease Epidemiology and Prevention 20 Future Research and Demonstration Key issues for continued research: Promised public health interventions Evaluating state prevention and control programs Industry practice monitoring and counteraction Translating the decline in youth and adult dependence Disparate population interventions Health impacts of changing products Most cost-effective interventions locally and internationally PHC 331: Chronic Disease Epidemiology and Prevention 21 Chapter 6: Diet and Nutrition PHC 331: Chronic Disease Epidemiology and Prevention 1 Consequences and Causes of Poor Nutrition Chart Causes Poor Diet/Nutrition: Consequences *Social and cultural factors *High in total calories, *Obesity *Poor social/family saturated fat, animal *CHD support meat, sugar, salt, and *Diabetes *School lunch policies alcohol *Selected cancers *Lack of education about *Low in fruit, vegetables, *Dental caries diet whole grains, fiber, *High blood pressure *Food industry marketing unsaturated oils *Psychological effect (esp. to children) *Eating out *Watch television At-risk Populations *Infants/elderly *Poor *Undereducated *Urban populations *Racial/ethnic minorities *Family with both parents working outside the home Adapted from Remington et al. (2010) PHC 331: Chronic Disease Epidemiology and Prevention 2 Significance Cardiovascular disease and cancer, followed closely by Type II diabetes, are the three main causes of mortality in the world, and are chiefly caused by an imbalance of nutrition High blood pressure/cholesterol Inversely, micronutrient deficiencies account for 15% of childhood diseases PHC 331: Chronic Disease Epidemiology and Prevention 3 Pathophysiology – Fruits and Vegetables Lowers chronic disease risk High levels of dietary fiber, vitamin C, E, folic acid, etc. Antioxidants and beta-carotenes Reduction of serum cholesterol Manages body weight through high contents of water, fiber, low fat content PHC 331: Chronic Disease Epidemiology and Prevention 4 Pathophysiology – Dietary Fiber Studies show that an increase in dietary fiber result in a lower chance of CHD/certain cancers Increases stool bulk, increases food’s entry and exit times, lowers risk for carcinogens in the body Soluble fiber can lower cholesterol Binds bile acids and prevents reabsorption High fiber, research shows, has an inverse relationship with insulin levels PHC 331: Chronic Disease Epidemiology and Prevention 5 Pathophysiology – Dietary Fat and Red Meat Different kinds of fat Trans fat and saturated fats – adverse toward health Omega-3 fatty acids and monounsaturated fats – benefit health Reduction of saturated fat by intake by small increments lowers heart attack risk rates by 25% Hypothesis is that omega-3 fatty acids alter the immune system’s response to cancer Red meat – both positive and negative effects + — high in iron, vitamins A, B12, protein - — risk of colorectal cancer, formation of mutagenic free radicals in stomach PHC 331: Chronic Disease Epidemiology and Prevention 6 Pathophysiology – Dairy Products and Milk Low fat milk intake shown to lower risk of osteoporosis, CVD, colon cancer Contains fatty acids Calcium content lowers lipid collection and higher lipid excretion rates 2% and whole milk are high in saturated fat and calories PHC 331: Chronic Disease Epidemiology and Prevention 7 Pathophysiology – Sugar-Sweetened Beverages Caloric sweeteners – “all caloric carbohydrate sweeteners, such as table sugar, honey, and high fructose corn syrup, and excludes naturally occurring sugars and artificial sweeteners” (Remington et al. 2010) Consumption of beverages with caloric sweeteners increases risk of obesity and cavities Increased consumption over the last 30 years has shown spiked levels of excessive consumption PHC 331: Chronic Disease Epidemiology and Prevention 8 High-Risk Populations – Sex U.S. men – higher intake of red meat, dairy U.S. women – higher intake of fruits, vegetables, salts, cholesterol Greater importance on eating healthily PHC 331: Chronic Disease Epidemiology and Prevention 9 High-Risk Populations – Age and Life Course Young and old are susceptible to poor nutrition Young – targeted by food industry to eat energy-dense foods; poor diet habits developed in youth tend to carry into adulthood Old – lower metabolism and physical activity, changes in taste and smell; 80% of elderly need improvements PHC 331: Chronic Disease Epidemiology and Prevention 10 High-Risk Populations – Race and Ethnicity African Americans and Caucasians increased total energy-dense foods from 1971 and 2002 Racially diverse populations, on average in the United States, have lower access to fresh fruits and vegetables Sociocultural and behavioral factors influence the dietary variety of the three major racial groups in the United States African American, Caucasian (white), and Mexican American PHC 331: Chronic Disease Epidemiology and Prevention 11 High-Risk Populations – Income As wealth decreases, direct relationship between the ability to acquire healthy foods Similarly, energy-dense foods are more likely to be consumed by those with lower income This is partly due to the inaccessibility, such as the high price and the lack of larger stores that support a variety of nutritional fruits and vegetables in urban/low-income areas PHC 331: Chronic Disease Epidemiology and Prevention 12 High-Risk Populations – Education Income and education have a corollary relationship, so both affect chronic disease outcome at similar rates Higher consumption of fruits/vegetables has been linked to higher education, and those with the most education are more likely to spend more per capita on these foods PHC 331: Chronic Disease Epidemiology and Prevention 13 High-Risk Populations – Other Geographic distribution Developed countries have higher diets with animal products and saturated fats Fish consumed more frequently in coastal regions Industrial development and immigration As a country shifts from underdeveloped to developed, chronic disease patterns can occur in as little as one generation Time trends Larger portion sizes appeared over time Higher kcal consumption for both men (+196kcal) and women (+283 kcal) PHC 331: Chronic Disease Epidemiology and Prevention 14 Barriers to Healthy Eating Individual preference Appearance, taste, texture Community and family Environments that support positive food choices make it easier to follow a healthy diet Lowest cost foods – least nutritious Fast-food density has been shown to be connected to poor nutrition Parental modeling affects familial diet among adolescents Families with both parents working outside the home have increased chances of seeking nutrition in energy-dense, unhealthy foods PHC 331: Chronic Disease Epidemiology and Prevention 15 Primary Prevention Policy Dietary Guidelines created by the US Department of Health and Human Service Areas of consideration include adequate nutrients within calorie needs, weight management, physical activity, fats, carbohydrates, sodium and potassium, alcoholic beverages, food safety Emphasizes a balanced diet An early nutritional guide developed in the 1940s by the U.S. From “Basic Seven” to Department of Agriculture, CC BY 2.0, via Wikimedia Commons “MyPlate” PHC 331: Chronic Disease Epidemiology and Prevention 16 Primary Prevention Policy, contd. Food Pyramid nutritional policy, developed in 1992 by the USDA. The current nutritional policy, MyPlate, developed in 2011. Image by the USDA College, Public Domain, via Wikimedia Image by OpenStax College, CC BY 3.0, via Wikimedia Commons Commons PHC 331: Chronic Disease Epidemiology and Prevention 17 Surveillance Various nutritional analyses that make up the National Nutrition Monitoring System Food disappearance programs chart the available consumable foods Food questionnaires used by epidemiologists to chart frequency of intake and a list of consumed foods Effective because participants are likely to remember recent food choices, as opposed to long-term dietary analyses PHC 331: Chronic Disease Epidemiology and Prevention 18 Large-Scale Initiatives Origins in the 1980s – National Cancer Institute/Kelloggs Campaign National Fruit and Vegetable Program 1% or Less Campaign Site-based interventions Workplace Schools Faith-based PHC 331: Chronic Disease Epidemiology and Prevention 19 Large-Scale Initiatives, contd. Population-specific initiatives Community approaches in urban areas Federal safety net School lunch programs Supplemental Nutrition Assistance Program (formerly Food Stamps) Eliminating racial disparities Heart to Heart Program PHC 331: Chronic Disease Epidemiology and Prevention 20 Large-Scale Initiatives, contd. Policy approaches Agricultural policies – which crops are produced Nutrition right-to-know – advocacy groups attempt to make nutritional assessments in restaurants more accessible School wellness policies – improved physical activity programs and healthy food options in vending machines Advertising to children PHC 331: Chronic Disease Epidemiology and Prevention 21 Chapter 7: Physical Activity PHC 331: Chronic Disease Epidemiology and Prevention 1 Consequences Affects physiological, psychological, societal of health Reduces chance of premature death, developing CHD/diabetes/colon cancer Promotes healthy bones and joints Less falls and functional dependency in older adults PHC 331: Chronic Disease Epidemiology and Prevention 2 Consequences, contd. Causes Consequences *Psychosocial (motivation *Obesity *Self-efficacy *CHD *Social/cultural factors *Diabetes *Physical environment *Colon cancer *Perceptions of Physical Inactivity *High blood pressure competence in sports *Falls/osteoporosis *Enjoyment *Psychological effects At-risk Populations *Older adults *Adolescents *Women *Those with low incomes *Overweight adults *Those with conditions that limit movement *Injured or disabled individuals Adapted from Remington et al. (2010) PHC 331: Chronic Disease Epidemiology and Prevention 3 Pathophysiology Physical activity – movement produced by skeletomuscular system that burns energy Occupational and nonoccupational Contrasted with exercise Exercise Repetitive movement used to maintain physical fitness Physical fitness Achievable attributes related to physical activity Cardiorespiratory, muscular, metabolic, morphological, motor Frequency – number of times PA is performed Duration – minutes/hours PA is performed PHC 331: Chronic Disease Epidemiology and Prevention 4 Pathophysiology, contd. Intensity METs – Metabolic cost divided by resting metabolic rate MET-minutes – MET multiplied by minutes Kcal – MET-minutes times body weight Light intensity - 6 METs Activity dose Leisure – free choice periods of PA Occupation PA – done during paid employment PHC 331: Chronic Disease Epidemiology and Prevention 5 Pathophysiology, contd. Transportation PA – done while traveling to a destination Household PA – done during the maintenance of the home Family PA – done when performing the care of others PA affects all body systems that deal with the production of energy Lower risk of CHD PHC 331: Chronic Disease Epidemiology and Prevention 6 Distribution Needs constant updating to chart meaningful activity patterns Two primary population-based surveys used to measure physical activity: National Health Interview Survey Household survey Frequency, self-assessed intensity, duration Behavioral Risk Factor Surveillance System Phone-based survey Type, frequency, duration PHC 331: Chronic Disease Epidemiology and Prevention 7 Distribution, contd. Surveillance estimations of PA were created to unify results across the board: Recommended PA – moderate-intensity workouts, 30 minutes/day, 5 days/week; vigorous-intensity workouts, 20 minutes/day, 3 days/week Insufficient PA – more than 10 minutes spent doing moderate- to vigorous-intensity workouts, but infrequent levels Inactivity – Less than 10 minutes/week spent doing moderate- to vigorous-intensity workouts PHC 331: Chronic Disease Epidemiology and Prevention 8 High-Risk Groups Physical inactivity increases with age and is more common among women and ethnic minorities Highest among men between 18-24 years old Among adolescents, two guidelines for physical activity: Daily physical movement in lifestyle, and Three+ sessions of vigorous physical activity per week PHC 331: Chronic Disease Epidemiology and Prevention 9 Geographic Distribution Highest prevalence of activity was in urban centers, and the lowest in rural areas Built environments may play a part in how much physical activity a population performs Land use patterns, transportation systems, sidewalk development, trail systems, etc. PHC 331: Chronic Disease Epidemiology and Prevention 10 Time Trends Though promoted thoroughly, proportion of adults who regularly exercise hasn’t undergone major growth over the years Adolescents have the same trend over time PHC 331: Chronic Disease Epidemiology and Prevention 11 Modifiable Risk Factors Personal, psychological, and confidence levels all attribute to a person’s choice to have a physically active lifestyle Barriers include “lack of time, motivation, social support, facilities, and knowledge of ways to become more physically active” (Remington et al. 2010) Health conditions also contribute to physical inactivity, and the positive response felt by not being inactive may worsen the health condition PHC 331: Chronic Disease Epidemiology and Prevention 12 Prevention In the United States, national health objectives are developed to set guidelines for activity objectives Healthy People 2010 US Preventative Services Task Force The Guide to Clinical Preventive Services Goals include to establish recommendations for population health, increase overall physical activity in a variety of strata, reduce leisure time that lacks physical activity, etc. PHC 331: Chronic Disease Epidemiology and Prevention 13 Environmental and Policy Factors Policy changes frequently begin as grassroots programs Recently, however, many coordinated efforts between school systems, public health offices, and these grassroots programs have been implemented Examples of policy efforts include ease of access to bicyclists and walkers, requiring physical education in school, activity programs through local recreation departments Environmental factors include the inclusion of safe stairwells in lobbies, providing an alternative to elevators PHC 331: Chronic Disease Epidemiology and Prevention 14 Public Health Interventions Transtheoretical Model Precontemplation, contemplation, action, maintenance, relapse Project Active – an individual-based project Home exercise vs. traditional exercise (health club/gym) Home exercise group aimed for thirty minutes of moderate activity per day, unique to the user’s lifestyle, whereas traditional group took exercise programs offered by the health club By the end of the study, smaller decline in home exercise group PHC 331: Chronic Disease Epidemiology and Prevention 15 Public Health Interventions, contd. Work sites, schools, assisted living facilities – all are options for intervention-based programs Transdisciplinary partnerships are very effective ways of promotion Example – teams from the Department of Transportation, state education systems, nonprofit organizations, and healthcare facilities worked together to form the National Safe Routes to School Task Force National Coalition for Promoting Physical Activity President’s Council on Physical Fitness and Sports State Governor’s Council on Physical Fitness State Health Department Physical Activity Initiatives and Campaigns PHC 331: Chronic Disease Epidemiology and Prevention 16 Measurement of Physical Activity – Future Research More work done with questionnaire development and surveys Quantification of popular trends in physical activities A difficulty to overcome in the research is inaccuracy due to self-analysis PHC 331: Chronic Disease Epidemiology and Prevention 17 Adolescent Physical Activity – Future Research Relatively recent adoption of guidelines for school programs that promote physical activity established a framework for analysis Additional studies needed to strengthen findings, especially in young women, and the balance between adequate nutrition and activity levels PHC 331: Chronic Disease Epidemiology and Prevention 18 Environmental and Policy Changes – Future Research Continued efforts required to effect policy changes designed to promote activity in communities Working with neighborhood coalitions Writing to local papers Lobbying for changes made by city planners Forming position statements for agencies Funding is required to research effectiveness of already established programs, especially those in disadvantaged communities PHC 331: Chronic Disease Epidemiology and Prevention 19 Older Adults – Future Research Baby boomer generation in need of study to understand efficacy and effectiveness of policies centered around the elderly PHC 331: Chronic Disease Epidemiology and Prevention 20 Chapter 10: Diabetes PHC 331: Chronic Disease Epidemiology and Prevention 1  Significance One of the ten major causes of death in the United States since the 1930s Responsible for hundreds of thousands of deaths each year Underreported because diabetes leads to the cause of death but doesn’t cause death By Blausen.com Staff. "Blausen gallery 2014". Wikiversity Journal of Medicine. (Own work) CC BY itself 3.0, via Wikimedia Commons PHC 331: Chronic Disease Epidemiology and Prevention 2  Diabetes Mellitus Diabetes is a chronic disease that occurs when the pancreas is no longer able to make insulin, or when the body cannot make good use of the insulin it produces. Insulin is a hormone made by the pancreas, that acts like a key to let glucose from the food we eat pass from the blood stream into the cells in the body to produce energy. All carbohydrate foods are broken down into glucose in the blood. Insulin helps glucose get into the cells. Not being able to produce insulin or use it effectively leads to raised glucose levels in the blood (known as hyperglycaemia). Over the long-term high glucose levels are associated with damage to the body and failure of various organs and tissues. PHC 331: Chronic Disease Epidemiology and Prevention 3  Significance of Diabetes Mellitus About 422 million people worldwide have diabetes, the majority living in low-and middle-income countries, and 1.6 million deaths are directly attributed to diabetes each year. Both the number of cases and the prevalence of diabetes have been steadily increasing over the past few decades. There is a globally agreed target to halt the rise in diabetes and obesity by 2025.(WHO, 2020) Types of Diabetes Mellitus:- 1- Type 1 Diabetes 2- Type 2 Diabetes 3- Gestational Diabetes PHC 331: Chronic Disease Epidemiology and Prevention 4 Significance, contd. Diabetes leads to various life-threatening complications: CVD Blindness Kidney failure Injury, infection, amputation of limbs Depression Diabetes carries a huge economic impact Partly due to long-term complications and prescription costs PHC 331: Chronic Disease Epidemiology and Prevention 5 Pathophysiology In general, Type II diabetics are unable to utilize insulin in the liver/muscle despite regular insulin production in these places As disease progresses, pancreas fails to increase insulin secretion Prediabetics: Impaired glucose tolerance (IGT) Impaired fasting glucose (IFG) Two classifications of diabetes complications Microvascular Macrovascular PHC 331: Chronic Disease Epidemiology and Prevention 6 Descriptive Epidemiology Relies on health survey data for monitoring No distinction between Types I and II Type II accounts for the majority of all diabetes cases, estimated at around 90%-95% Type II usually found in older adults, whereas Type I is associated with minors and adolescents PHC 331: Chronic Disease Epidemiology and Prevention 7 High-Risk Groups Not an equal distribution The elderly, racial minorities, lower socioeconomic status, family history Increased exposure to a variety of health complications, all of which increase substantially with age Tend to be higher in minority populations in the United States Native Americans/Alaska Natives two to three times higher than other US adults PHC 331: Chronic Disease Epidemiology and Prevention 8 High-Risk Groups, contd. Those with lower socioeconomic status, i.e. those with lower education and income, have an increased risk, as well Common factors include less access to care, less opportunities for education about diabetes, high stress levels Family history of diabetes strongly affects risk factor 2.4 times greater odds of acquiring Type II when there is a moderate familial risk 5.8 times greater when there is a high familial risk PHC 331: Chronic Disease Epidemiology and Prevention 9 Geographic Distribution In the United States, clear geographic regions show patterns in developing diabetes South/Southeastern at high risk, due to ethic makeup and obesity Where there are higher levels of obesity there are higher levels of diabetes Susceptibility to Type I diabetes shows a similarity across the different regions of the world PHC 331: Chronic Disease Epidemiology and Prevention 10 Time Trends Over time, diabetes has been one of the only CVD risk that has increased Due to age, ethnic diversity, obesity problem Increasing in all demographics over time This is true for both Types I and II However, due to timely response, medications and therapies, there hasn’t been an increase in diabetes-related complications over time PHC 331: Chronic Disease Epidemiology and Prevention 11 Modifiable Risk Factors – Type I Very few modifiable risks for Type I diabetes However, research has shown that there is some correlation between environmental factors Nutrition and viruses may come into play Type I patients were 43% more likely to have breastfed for less than 3 months and 63% more likely to consume cow’s milk before age three Enteroviruses Stress, higher maternal age at birth, birth order, birth weight, overnutrition are other possible risks PHC 331: Chronic Disease Epidemiology and Prevention 12 Modifiable Risk Factors – Type II Obesity – 80% of patients obese at diagnosis Distribution of fat also plays a role Those with a higher hip-to-waist ratio are more susceptible Dietary elements Whole grains, coffee, magnesium, peanut butter/nuts, low-fat dairy products, moderate alcohol consumption all been shown to reduce risk High saturated fat diets and increase red meat consumption have been linked to an increased risk of Type II PHC 331: Chronic Disease Epidemiology and Prevention 13 Modifiable Risk Factors – Type II, contd. Lack of physical activity Almost a linear relationship between frequency/intensity to diminished risks of Type II Diabetes Smoking Increased risk factor Factors that reduce chance of developing Type II: Relatively low BMI, high fiber diet, high polyunsaturated fat diet, 30 minutes of moderate exercise a day, smoke-free, less than half a serving of alcohol per day PHC 331: Chronic Disease Epidemiology and Prevention 14 Risk factors of Gestational Diabetes Mellitus PHC 331: Chronic Disease Epidemiology and Prevention 15 Symptoms of Type 1 Diabetes PHC 331: Chronic Disease Epidemiology and Prevention 16 Symptoms of Type 2 Diabetes PHC 331: Chronic Disease Epidemiology and Prevention 17 Complications Often external factors that are intrinsic to developing Type II often increase the risk of complications Risks can be reduced by working with health care professionals to manage macro- and microvascular complications PHC 331: Chronic Disease Epidemiology and Prevention 18 Major complications of Diabetes PHC 331: Chronic Disease Epidemiology and Prevention 19 Causes, Consequences, Risk Populations Chart Consequences Causes *Coronary heart disease *Obesity *Stroke *Physical inactivity Type 2 Diabetes *Peripheral vascular *Poor diet disease *Smoking *End-stage renal disease *Blindness *Lower leg amputations *Disability *Depression At-risk Populations *Poor pregnancy *Elderly outcomes *Poor *Premature mortality *Less educated *Minorities *Persons with a family history of diabetes Adapted from Remington et al. (2010) PHC 331: Chronic Disease Epidemiology and Prevention 20 Prevention and Control – Type I Prevention starts with identification of disease Diabetes Prevention Trial (DPT) Locating effective prevention strategies isn’t currently economical or relatively easy PHC 331: Chronic Disease Epidemiology and Prevention 21  Prevention and Control – Type II Unlike Type I, there are clear plans for prevention – both lifestyle and pharmacological interventions Studies in both China, Finland and the United States, where screenings of diabetics were calculated and then controlled through differing variables – exercise, diet, etc. Results were conclusive – reduction in diabetes after a few years of PHC 331: Chronic Disease Epidemiology and Prevention 22 participation Prevention and Control in Youth – Type II Not many studies conducted to research Type II diabetes in youth because so few cases exist Interventions done in school systems to increase physical activity were enforced, but insulin levels were not measured There has been increased development in plans to prevent Type II, as opposed to treat it in youth Early detection of prediabetes PHC 331: Chronic Disease Epidemiology and Prevention 23 Prevention and control of Gastetional diabetes PHC 331: Chronic Disease Epidemiology and Prevention 24 Screening and Early Detection Prediabetes – blood glucose between 100-126 mg/dL Type I – not recommended Type II – not cost effective, but utilized in “high risk” groups; fasting glucose >126mg/dL considered diagnostic Gestational Diabetes – shown to reduce fetal morbidity/mortality; recommended for “high risk” groups; 100g OGTT administered upon positive test PHC 331: Chronic Disease Epidemiology and Prevention 25 Treatment, Rehab, Recovery Type I Diabetes Control and Complications Trial Physical activity an important goal for treatment Type II Weight management, caloric restriction, physical activity Pharmacotherapy – BP, tobacco nonuse, aspiration may be just as important as glucose control in many cases Treatment involves hands-on patient interaction Frequent evaluations PHC 331: Chronic Disease Epidemiology and Prevention 26 Public Interventions National Diabetes Prevention and Control Program Defining the Diabetes Burden Conducting Applied Translation Research State-Based Diabetes Control Programs National Diabetes Partnerships and Programs Prevention Research Centers, Racial and Ethnic Approaches to Community Health, Steps to a Healthier US Indian Health Service Division of Diabetes Treatment/Prevention Diabetes Research and Training Centers PHC 331: Chronic Disease Epidemiology and Prevention 27 Chapter 11: High Blood Pressure PHC 331: Chronic Disease Epidemiology and Prevention 1  Significance Hypertension - or elevated blood pressure - is a serious medical condition that significantly increases the risks of heart, brain, kidney and other diseases. An estimated 1.13 billion people worldwide have hypertension, most (two-thirds) living in low- and middle-income countries. In 2015, 1 in 4 men and 1 in 5 women had hypertension. Fewer than 1 in 5 people with hypertension have the problem under control (WHO,2019) PHC 331: Chronic Disease Epidemiology and Prevention 2  Blood Pressure Hypertension is a major cause of premature death worldwide. One of the global targets for no communicable diseases is to reduce the prevalence of hypertension by 25% by 2025 (baseline 2010). Blood pressure is the force exerted by circulating blood against the walls of the body’s arteries, the major blood vessels in the body. Hypertension is when blood pressure is too high. Blood pressure is written as Chronic PHC 331: two numbers. Theand Disease Epidemiology first Prevention 3  The second (diastolic) number represents the pressure in the vessels when the heart rests between beats. Hypertension is diagnosed if, when it is measured on two different days, the systolic blood pressure readings on both days is ≥140 mmHg and/or the diastolic blood pressure readings PHC 331: Chronic on both Disease Epidemiology days is and Prevention 4 Causes, Consequences, High-Risk Groups Causes Consequences *Obesity *Cardiovascular disease *Physical inactivity *Neurological disease *Alcohol intake High Blood Pressure (stroke) *Dietary sodium and *Kidney disease potassium intake *Renal failure *Genetics *Premature death At-risk Populations *African American ancestry *Family history of high blood pressure *Men *Older women Adapted from Remington et al. (2010) PHC 331: Chronic Disease Epidemiology and Prevention 5 Pathophysiology “Mean arterial pressure is the product of cardiac output…and systematic vascular resistance” (Remington et al. 2010). Kidney, sympathetic nervous system, renin-angiotensin system all play central roles BP regulation A “normal” body maintains intake and output in equilibrium PHC 331: Chronic Disease Epidemiology and Prevention 6 Pathophysiology, contd. The various types of hypertension exhibit impaired pressure natriuresis Either intra- or extrarenal Increased activity of the sympathetic nervous system also associated with hypertension Vasoconstriction/sodium retention PHC 331: Chronic Disease Epidemiology and Prevention 7 Significance Across all populations, HBP is a severe issue for healthcare workers Second largest contributor to disease in developed and developing countries 7.1 million of annual deaths are attributed to high blood pressure The correlation between HBP and CV mortality higher in younger subjects, though mortality naturally occurs in older populations PHC 331: Chronic Disease Epidemiology and Prevention 8 Significance, contd. HBP is the leading contributor to stroke – shown as consistent across a variety of studies More than twice as high in hypertensive category Nondependent on race/sex Higher chance of congestive heart failure Higher chance of cardiovascular disease The effects of high blood pressure do vary slightly depending on race, age, regions PHC 331: Chronic Disease Epidemiology and Prevention 9 High-Risk Populations Age As we age, our average blood pressure increases across most populations True for both men and women Systolic blood pressure increases throughout lifespan Diastolic blood pressure Increases until 50 years old, and then remains constant and then decreases Data is limited because lack of followup Those with starting SBP < 140 mmHg and DBP 85-89 mmHg are more likely to develop HBP PHC 331: Chronic Disease Epidemiology and Prevention 10 Time Trends Over time, 1971-1991 a steady decline in both systolic and diastolic BP had been seen across all observable age groups, races, sexes Omitting African American men, 50+, who suffered a small increase This downward movement indicates that environmental/behavioral effects mitigated higher BP Increase began after 1991 in the United States, especially in the elderly ad in women Corollary to increased BMI PHC 331: Chronic Disease Epidemiology and Prevention 11 Causes – Genetic Factors Those predisposed to high blood pressure are susceptible Difficult to assess genetic causes Alteration of specific non-allelic gene difficult to trace because HBP looks the same in everyone Alleles and haplotypes inspection is compromised 90% of the time PHC 331: Chronic Disease Epidemiology and Prevention 12 Causes – Obesity In the United States, those with higher BMIs progressively experience blood pressure problems 50% of new cases attributable to being overweight Corroborated by nonpharmacological interventions PHC 331: Chronic Disease Epidemiology and Prevention 13 Causes – Salt Intake Sodium chloride intake attributable to the development of HBP Salt compromises kidneys After a long exposure to high salt intake, no longer able to excrete sodium, which leads to increased volume of blood in the body Confirmed by random control testing of sodium reduction in diets PHC 331: Chronic Disease Epidemiology and Prevention 14 Causes – Potassium Intake Increased potassium – lower blood pressure SBP and DBP “Administration of dietary potassium increases renal sodium and chloride excretion, reduces blood volume, and decreases blood pressure” (Remington et al. 2010) PHC 331: Chronic Disease Epidemiology and Prevention 15 Causes – Alcohol Intake Unclear direct link between high blood pressure and high alcohol intake, but hypertensive effects of extensive alcohol use shown in various studies When a reduction in alcohol intake is reported, lower blood pressure is also reported PHC 331: Chronic Disease Epidemiology and Prevention 16 Symptoms of Hypertension PHC 331: Chronic Disease Epidemiology and Prevention 17 Screening and Early Prevention Screening is beneficial because testing methods are reliable and effective for those with hypertension Screening is inexpensive, but should be targeted toward high-risk patients in particular 76% of hypertension victims are aware of their condition, By National Heart Lung and Blood Insitute (NIH) [ Public Domain], via Wikimedia Commons despite readily available testing PHC 331: Chronic Disease Epidemiology and Prevention 18 Types of Hyptersion PHC 331: Chronic Disease Epidemiology and Prevention 19 Complications of Hypertension PHC 331: Chronic Disease Epidemiology and Prevention 20 Lifestyle Changes, contd. Nonpharmacological, lifestyle choices, contd. Dietary pattern – not one factor that influences diet, but large- scale changes DASH Trial: three various diets observed for 11 weeks; one – low fruits, veggies, dairy, average United States fat content; two – fruits and vegetables; three – DASH diet (high fruits, vegetables, low-fat dairy, reduced saturated and total fat DASH diet effective for those with HBP DASH diet current recommendation for lowering high blood pressure PHC 331: Chronic Disease Epidemiology and Prevention 21 Lifestyle Changes Nonpharmacological, lifestyle choices Weight reduction – less drug therapy needed if following a diet aimed at fat/weight reduction Salt reduction – especially effective for hypertensive as opposed to normotensive Less drug therapy needed for those with a low-salt diet Increase in dietary potassium – inverse relationship with higher potassium consumption and blood pressure in various meta- analyses Especially effective for hypertensive and African Americans PHC 331: Chronic Disease Epidemiology and Prevention 22 Lifestyle Changes, contd. Nonpharmacological, lifestyle choices, contd. Alcohol intake moderation – 25% reduction lowers SBP by 3.3 mmHg and DPB by 2.0 mmHg Limited intake to 2 drinks per day (men) and 1 drink per day (women and low-weight individuals Physical activity – SBP reduction 3.5 mmHg and DBP reduction 2.5 mmHg Study of physical activity currently limited; inconclusive toward women, African Americans, and weight training (aerobic only) PHC 331: Chronic Disease Epidemiology and Prevention 23 Prevention and Control of Hypertension PHC 331: Chronic Disease Epidemiology and Prevention 24 Secondary Prevention: Pharmacological Treatment Goal of secondary prevention: avoiding the negative effects of HBP Recommended for both hypertensive individuals with no complications (risk factors) Thiazide diuretic initially Calcium channel blockers Angiotensin-converting enzyme inhibitors Angiotensin type I receptor blockers Beta-blockers PHC 331: Chronic Disease Epidemiology and Prevention 25 Population-level Changes Aim of intervention is to lower blood pressure across an entire population Various community-based projects aim to translation research into action and management of blood pressure The processes for lowering blood pressure at a population-level are the same as those outlined in individual- based programs, outline above PHC 331: Chronic Disease Epidemiology and Prevention 26 Chapter 12: High Blood Cholesterol PHC 331: Chronic Disease Epidemiology and Prevention 1  Cholesterol PHC 331: Chronic Disease Epidemiology and Prevention 2 Cholesterol Definition :- is a waxy, fat-like substance that's found in all the cells in your body. Your body needs some cholesterol to make hormones, vitamin D, and substances that help you digest foods. Cholesterol is transmitted in the blood through PHC 331: Chronic Disease Epidemiology and Prevention 3  Lipoprotien Intermediate density – cholesterol + triglycerides transport Very low density – triglycerides LDL : Low density consist of High Fat, Low Protein HDL : High density :Low Fat, High Protein PHC 331: Chronic Disease Epidemiology and Prevention 4 Lipoprotein PHC 331: Chronic Disease Epidemiology and Prevention 5  Fat PHC 331: Chronic Disease Epidemiology and Prevention 6 Significance Many different people are at risk for coronary heart disease Hypercholesterolemia 16.5% of population between 20-74 have high cholesterol in the United States, and nationally high average Many healthcare resources needed to be expended to screen and treat hypercholesterolemia PHC 331: Chronic Disease Epidemiology and Prevention 7 Pathophysiology and Genetics Insoluble in water Transported in lipoproteins throughout bloodstream Lipids + apoproteins = lipoproteins 4 types of lipoproteins: Low density – integral to atherosclerotic development Very low density – triglycerides Intermediate density – cholesterol + triglycerides transport High density – cholesterol removed from the body transport Inverse correlation between high density lipoproteins and coronary heart disease PHC 331: Chronic Disease Epidemiology and Prevention 8 Pathophysiology and Genetics, contd. Cholesterol is needed to maintain regular bodily function Problems arise when abundance of cholesterol is present Accumulates in artery walls Plaque can develop Fatty streaks are earliest signs of accumulation Atheromas are advanced Can be calcified, hemorrhage, ulcerate Genetics important to assigning cholesterol levels PHC 331: Chronic Disease Epidemiology and Prevention 9 Abnormalities include hyperlipidemia/dyslipidemia Causes, Consequences, High-Risk Groups Consequences Causes *Coronary heart disease *Diets with high saturated High Cholesterol *Atherosclerosis fats *Stroke *Genetics *End organ damage *Obesity and metabolic *Premature death and disorders disability *Physical inactivity *High health care costs *Smoking At-risk Populations and treatment *Hypothyroidism *Men 45 and older *Renal disease *Women 55 and older *Diabetes mellitus *Low socioeconomic status *Steroid therapy *Diabetics *Those with: -Known atherosclerosis -Genetic lipid disorder -Chronic kidney disease -History of a prior stroke -History of coronary artery disease Adapted from Remington et al. (2010) PHC 331: Chronic Disease Epidemiology and Prevention 10 High-risk populations Highest risk – known atherosclerotic cardiovascular disease Rate increases when prior CV event occurs Older are at more risk Especially men older than 45 and women older than 55 PHC 331: Chronic Disease Epidemiology and Prevention 11 Geographic Distribution Beijing, China had the lowest hypercholesterolemia among men/women Ticino, Switzerland / Novi Sa, Yugoslavia had the highest European countries in general are more disposed to high serum cholesterol levels PHC 331: Chronic Disease Epidemiology and Prevention 12 Time Trends Steadily decreasing in the United States since the 60s Contributed directly to the decline in coronary heart diseases in the United States in recent years PHC 331: Chronic Disease Epidemiology and Prevention 13 Modifiable Risk Factors Biggest modification – reduction in dietary fat/saturated fat Dose response relationship among saturated/trans fat intake and low-density lipoprotein levels Three types of fat: Saturated – saturated with hydrogen; no double bonds Monounsaturated – one double bond Polyunsaturated – two or more bonds Saturated fatty acids raise cholesterol levels by decreasing activity of low density lipoprotein receptors PHC 331: Chronic Disease Epidemiology and Prevention 14 Modifiable Risk Factors, contd. Polyunsaturated fatty acids – omega-6 and omega-3 Omega-6 lowers LDLs and some HDLs Omega-3 lowers triglyceride and LDL levels Monounsaturated fatty acids Reduces LDLs and minimally reduces HDL Trans fatty acids Raises LDLs and lower HDLs, raises triglycerides Obesity is also positive-corollary to total cholesterol levels Smoking/inactivity – lower HDLs and higher risk of CHD PHC 331: Chronic Disease Epidemiology and Prevention 15 Prevention Diet is the cornerstone for change when it comes to lowering cholesterol levels, however: Cholesterol-lowering medication also substantially beneficial Two approaches to prevention: Population strategy – lifestyle alteration Clinical strategy – addressing the needs of those with direct cause for cholesterol reduction PHC 331: Chronic Disease Epidemiology and Prevention 16 Top food to increase (HDL) Cholesterol PHC 331: Chronic Disease Epidemiology and Prevention 17 Screening Screening is a fivefold process with treatment, nutritional changes, weight management, increased physical activity Lipid panels are obtained in a fasting state Recommended for those over 20 years old, every five years Baseline total cholesterol levels vary by 5 mg/dL on a given day HDL levels by 1.5 mg/dL PHC 331: Chronic Disease Epidemiology and Prevention 18 Treatment – Population-based An emphasis is placed first on community education Dietary Guidelines for Americans details goals to decrease diseases like coronary heart disease Recommended for use starting as early as two years old Those with immediate cholesterol disorder, or those who have had a recent CHD event should be stricter and should follow a more rigid clinical approach PHC 331: Chronic Disease Epidemiology and Prevention 19 Treatment – Patient-based Lipoprotein count should be gathered if: 200 mg/dL cholesterol or higher HDL cholesterol lower than 40 mg/dL CHD risk factors (3+) Framingham 10-year Risk Score measures the risk percentage of having a CHD event based on risk factors, and outlines a goal level of low-density lipoproteins to have PHC 331: Chronic Disease Epidemiology and Prevention 20 Treatment – Antioxidants Historically, antioxidant use has been shown to decrease oxidation of LDLs However, now shown that antioxidants do not decrease atherosclerotic burden or prevent CHD events; further, vitamin intake with antioxidants may increase an event, and increase chance of lung cancer No longer recommended for lipid therapy PHC 331: Chronic Disease Epidemiology and Prevention 21 Treatment – Hormone Replacement Therapy Not recommended for lipid disorder treatment Increased risk suggested PHC 331: Chronic Disease Epidemiology and Prevention 22 Treatment – Children and Adolescents Atherosclerosis begins in childhood; progression linked to later high cholesterol High cholesterol is maintained in familial setting due to similar genetics and home environment Population approach – the same change in diet as adults, with an emphasis on fruits/vegetables Individualized approach – designed for at-risk youth PHC 331: Chronic Disease Epidemiology and Prevention 23 Public Health Interventions Public education, screening, intervention Community interventions from various groups Stanford Five City Project Pawtucket Heart Health Program Minnesota Heart Health Program PHC 331: Chronic Disease Epidemiology and Prevention 24 Future Research Due to substantial variation in medication benefits across a span of variables, more research needed to find a more even fit Optimal diet research Cholesterol disorders need further evaluation Behavior change and adherence need further initiatives PHC 331: Chronic Disease Epidemiology and Prevention 25 Chapter 13: Cardiovascular Disease PHC 331: Chronic Disease Epidemiology and Prevention 1 Types of Heart diseases PHC 331: Chronic Disease Epidemiology and Prevention 2 Causes, Consequences, High-Risk Groups Causes Cardiovascular Disease Consequences *High blood pressure (heart disease, stroke, and *Disability *Elevated blood peripheral vascular *Lost productivity cholesterol disease) *Large costs to health care *Cigarette smoking and system environmental tobacco *Depression smoke *Premature mortality *Physical inactivity At-risk Populations *Obesity (abdominal) *Elderly *Poor diet *Poor *Diabetes *Less educated *Minorities *Family history Adapted from Remington et al. (2010) PHC 331: Chronic Disease Epidemiology and Prevention 3 Significance Cardiovascular diseases (CVDs) are the number 1 cause of death globally, taking an estimated 17.9 million lives each year. CVDs are a group of disorders of the heart and blood vessels and include coronary heart disease, cerebrovascular disease, rheumatic heart disease and other conditions. Four out of 5CVD deaths are due to heart attacks and strokes, and one third of these deaths occur prematurely in people under 70 years of age.(WHO,2020) Variation by age, race, sex Highest mortality rates for CVD in the United States Leading cause of death of women in the United States Wide range of complications associated with CVD – disability, stroke, high blood pressure PHC 331: Chronic Disease Epidemiology and Prevention 4 Significance of Cardiovascular Diseases PHC 331: Chronic Disease Epidemiology and Prevention 5 Pathophysiology of CVD Cardiovascular disease is closely related to atherosclerosis Atherosclerosis – “A slowly progressive condition in which the inner layers of the artery walls become thick, irregular, and rigid” (Remington et al. 2010) Typically seen during middle-age or later, though atherosclerosis manifests in childhood Coronary heart disease, stroke, peripheral artery disease, congestive heart failure Each each associated with certain risk factors: CHD – high cholesterol Stroke – high blood pressure PAD – smoking/diabetes PHC 331: Chronic Disease Epidemiology and Prevention 6 Coronary Heart Disease – Significance, Pathophysiology Also known as ischemic heart disease or coronary artery disease “Several di