Diabetes Guidelines 2018 PDF

Can J Diabetes 42 (2018) S1–S5 Contents lists available at ScienceDirect Canadian Journal of Diabetes journal homepage: w w w. c a n a d i a n j o u r n a...

Can J Diabetes 42 (2018) S1–S5 Contents lists available at ScienceDirect Canadian Journal of Diabetes journal homepage: w w w. c a n a d i a n j o u r n a l o f d i a b e t e s. c o m 2018 Clinical Practice Guidelines Introduction Diabetes Canada Clinical Practice Guidelines Expert Committee Robyn L. Houlden MD, FRCPC Welcome to the Diabetes Canada 2018 Clinical Practice Guide- inappropriate variation in practice, promote efficient use of health- lines for the Prevention and Management of Diabetes in Canada. care resources, empower people living with diabetes, identify gaps Updated every five years, these comprehensive, evidence-based in knowledge, prioritize research activities, inform public policy, and guidelines represent the sixth set since their introduction in 1992; support quality control activities, including audits of practice (1). and the first under the new name of Diabetes Canada. In 2017, the The guidelines represent a summary of material and do not name of the Canadian Diabetes Association was changed to Dia- provide in-depth background clinical knowledge which is typi- betes Canada to reflect the seriousness of diabetes, and to increase cally covered more comprehensively in medical textbooks and review perception of the organization as being committed to helping all articles. They are not meant to provide a “menu-driven” or “cook- Canadians with diabetes, as well as to ending the disease. book” approach to diabetes care where the clinician has no discre- tion. In addition, they are unable to provide guidance in all circumstances and for all people with diabetes. People with dia- betes are a diverse and heterogeneous group; treatment decisions must be individualized. Guidelines are meant to aid in decision making by providing recommendations that are informed by the best available evidence; however, therapeutic decisions are made at the level of the relationship between the health-care provider and the individual with diabetes. That relationship, along with the The Diabetes Canada Clinical Practice Guidelines are intended importance of clinical judgement, can never be replaced by guide- to guide practice; inform general patterns of care; enhance diabe- line recommendations. Evidence-based guidelines try to weigh the tes prevention efforts in Canada; and reduce the burden of diabe- benefit and harm of various treatments; however, patient prefer- tes complications. The intended users are all health-care ences are not always included in clinical research and, as a result, professionals that are involved in the management of people with patient values and preferences must be incorporated into clinical diabetes and those at risk of developing diabetes, with a particu- decision making (2). For some clinical decisions, strong evidence lar focus on primary care or “usual care” providers. The guidelines is available to inform these decisions, and these are reflected in the are also intended for people living with diabetes. In this version, recommendations within these guidelines. However, there are many key messages directed at people living with this chronic disease have clinical situations where strong evidence is not currently avail- been added to each chapter. able, or may never become available due to feasibility issues. In those For these 2018 Clinical Practice Guidelines, volunteer members situations, the consensus of expert opinions, informed by what- of the Clinical Practice Guidelines Expert Committee have assessed ever evidence is available, is provided to help guide clinical deci- the relevant peer reviewed evidence published since the last guide- sions that need to be made at the level of the individual with lines in 2013 through a rigorous systematic review process. They diabetes. It is also important to note that clinical practice guide- have then incorporated the evidence into revised diagnostic, prog- lines are not intended to be a legal resource in malpractice cases nostic and therapeutic recommendations for the care of Canadi- as their more general nature renders them insensitive to the par- ans living with diabetes, as well as recommendations to delay the ticular circumstances of individual cases (1). onset of diabetes for at risk populations. The grading of all recom- mendations has been stringently reviewed by an Independent Methods Committee (see Methods chapter, p. S6). Key Changes The guidelines are meant to improve the quality of care and healthcare outcomes of Canadians living with diabetes. A primary A number of changes have occurred with the development of purpose is to address clinical care gaps that exist, i.e. discrepan- the 2018 Clinical Practice Guidelines, including: cies between evidence-based knowledge and day-to-day clinical practice. The guidelines also summarize key research findings and Expansion of the Expert Committee to include 135 health- make clinical decisions more transparent. They are meant to reduce care professional volunteers from across Canada with broader representation from more allied health/interprofessional stake- Conflict of interest statements can be found on page S5. holder groups. Expert Committee members bring expertise from 1499-2671 © 2018 Canadian Diabetes Association. The Canadian Diabetes Association is the registered owner of the name Diabetes Canada. https://doi.org/10.1016/j.jcjd.2017.10.001 S2 R.L. Houlden / Can J Diabetes 42 (2018) S1–S5 diverse practice settings across the country and include diagnosed with this serious chronic condition with potentially professionals from family medicine, endocrinology, internal devastating complications that affects all age groups. The World medicine, cardiology, neurology, nephrology, infectious disease, Health Organization estimates that, globally, high blood glucose is urology, psychiatry, psychology, obstetrics, ophthalmology, pedi- the third highest risk factor for premature mortality, after high blood atrics, nursing, dietetics, pharmacy, chiropractics, exercise physi- pressure and tobacco use (5). In 2015, the IDF estimated that 415 ology and others. million adults currently had diabetes and 318 million adults had Inclusion and active participation of informed people with dia- impaired glucose tolerance, putting them at high risk of develop- betes on the Expert Committee to ensure that their views and ing the disease in the future (4,6). Canada has also seen rising rates preferences inform the guideline development process and the of diabetes. In 2015, the estimated prevalence of diabetes was 3.4 recommendations, as well as development of key messages million or 9.3% of the population, and is predicted to rise to 5 million using lay terms directed at people living with diabetes. or 12.1% of the population by 2025, representing a 44% increase from Increased recognition of ethnocultural diversity in Canada and 2015 to 2025 (6). The estimated prevalence of prediabetes in adults its relationship with diabetes care. in Canada in 2015 was 5.7 million or 22.1% of the population (6). Increased involvement of Indigenous authors, organizations and Diabetes is the leading cause of blindness, end stage renal disease health-care providers working with Indigenous populations and (ESRD) and non-traumatic amputation in Canadian adults (see Reti- communities in the development of recommendations related nopathy chapter, p. S210; Neuropathy chapter, p. S217; Foot Care to type 2 diabetes in Indigenous peoples. In addition, acknowl- chapter, p. S222). Cardiovascular disease (CVD) remains the leading edgment of the legacy of colonization and residential schools cause of death in individuals with diabetes and occurs two- to four- and their ongoing effects on Indigenous health, as well as the fold more often than in people without diabetes (see Cardiovas- call to action of the 2015 Truth and Reconciliation Commis- cular Protection in People with Diabetes chapter, p. S162; Screening sion (3). for the Presence of Cardiovascular Disease chapter, p. S170). People Addition of new material on diabetes and driving, and post- with diabetes are over 3 times more likely to be hospitalized with transplant diabetes. CVD, 12 times more likely to be hospitalized with ESRD and over More rigorous systematic review of literature with the assis- 20 times more likely to be hospitalized for a non-traumatic lower tance of the McMaster Evidence Review and Synthesis Centre; limb amputation compared to the general population (7). Diabe- a former Evidence-based Practice Centre (EPC) designated by tes complications are also associated with premature death and it the U.S. Agency for Healthcare Research and Quality (AHRQ) is estimated that 1 of 10 deaths in Canadian adults was attribut- under the auspices of their Evidence-based Practice Program able to diabetes in 2008/09 (7). Thirty per cent of people with dia- which has completed high quality reviews for the Canadian Task betes have clinically relevant depressive symptoms (8); and Force on Preventive Health Care and the Public Health Agency individuals with depression have an approximately 60% increased of Canada. risk of developing type 2 diabetes (9) (see Diabetes and Mental More rigorous review of the grading of recommendations by Health chapter, p. S130). an Independent Methods Review (IMR) Committee. In the event Diabetes and its complications increase costs and service pres- of a discordance between author-assigned grade and IMR- sures on Canada’s publicly funded health-care system. This is because assigned grade, the recommendation was arbitrated by an IMR of an increased use of health services, loss of productivity and the co-chair. long-term support needed to manage diabetes-related complica- Wider external review by specialists, community primary care tions. Among adults aged 20 to 49 years, those with diabetes were providers, academic Departments of Family Medicine across 2 times more likely to see a family physician and 2 to 3 times more Canada, and specialty and disease support organizations. likely to see a specialist (3). Also, people with diabetes were 3 times Additional efforts to manage and minimize conflict of interest more likely to require hospital admission in the preceding year with among all Expert and Steering Committee members. longer lengths of stay (2) (see In-Hospital Management of Diabe- Expanded harmonization of recommendations through col- tes chapter, p. S115). Canada has been identified as the country with laboration with other organizations, including the Canadian Car- the seventh highest spending on diabetes-related health expendi- diovascular Society (CCS), Hypertension Canada, and the ture, totaling 17 billion US dollars in 2015 (4). With the aging of Canadian Cardiovascular Harmonization of National Guide- Canada’s population, the total direct health-care costs associated lines Endeavour (C-CHANGE). with diabetes are expected to continue to increase (10). Expanded dissemination and implementation strategies to support all recommendations with increased use of web- based technology. Prevention of Diabetes A key message throughout the guidelines remains the impor- Prevention of type 1 diabetes has not yet been successful, but tance of individualizing therapy for the person with diabetes. It is remains an active area of research (see Reducing the Risk of Devel- hoped that primary care providers and other health-care profes- oping Diabetes chapter, p. S20). However, there is good evidence sionals who care for people with diabetes or those at risk of dia- that the onset of type 2 diabetes can be delayed or prevented through betes will continue to find the guidelines an indispensable resource. a number of strategies, including healthy behaviour interventions If properly applied, the guidelines should lead to improved quality (physical activity, weight loss), certain dietary patterns and phar- of care, reduced morbidity and mortality from diabetes and its com- macotherapy (see Reducing the Risk of Developing Diabetes chapter, plications, and a better quality of life for Canadians living with this p. S20). An obesity epidemic is currently paralleling the diabetes chronic disease. epidemic worldwide (see Weight Management in Diabetes chapter, p. S124) with over 60% of Canadian adults and close to one-third (31.5%) of children and adolescents having overweight or obesity The Challenge of Diabetes (11,12). There is an urgent need for governments to develop and evaluate strategies to prevent and treat rising rates of obesity and The International Diabetes Federation (IDF) has identified dia- promote physical activity and reduction of sedentary time (see Physi- betes as one of the largest global health emergencies of the 21st cal Activity and Diabetes chapter, p. S54). In addition, Canada’s century (4). Each year, more and more people worldwide are diverse population, with some ethnic groups disproportionately  R.L. Houlden / Can J Diabetes 42 (2018) S1–S5 S3 affected by diabetes, requires that health promotion and disease Indigenous peoples in these guidelines (see Type 2 Diabetes and prevention and management strategies be culturally appropriate Indigenous Peoples chapter, p. S296) provides an important lens for and tailored to specific populations (see Self-Management Education recognizing the diabetes epidemic and challenges in providing dia- and Support chapter, p. S36; Organization of Care chapter, p. S27). betes care in these populations, and acknowledges the legacy of colo- It is becoming increasingly apparent that social determinants of nization and residential schools and their ongoing effects on health play an important role in risk of diabetes and its complica- Indigenous health, as well as the call to action of the 2015 Truth tions. Two large public health surveys, the Canadian Community and Reconciliation Commission (3). Health Survey (CCHS) (13) and the National Population Health Survey (14) have found that lower-income people are significantly more likely to develop diabetes. In the CCHS, the prevalence of type 2 dia- Optimal Care of Diabetes betes in the lowest income group was 4.14 times higher than in the highest income group (13); and, in the National Population Health Effective diabetes care should be delivered within the framework Survey, being in the low income group was associated with a 77% of the Chronic Care Model and centred around the individual who higher risk of developing type 2 diabetes (hazard ratio 1.77, 95% con- is practicing, and supported in, self-management (see Organization fidence interval 1.48–2.12) (14). The primary goals of public health of Care chapter, p. S27). To achieve this, an interprofessional team interventions to prevent type 2 diabetes include the maintenance with the appropriate expertise is required, and the system needs of a healthy body weight, physical activity and healthy eating (see to support and allow for sharing and collaboration between primary Nutrition Therapy chapter, p. S64; Physical Activity and Diabetes care and specialist care, as needed. A multifactorial approach uti- chapter, p. S54); however, an individual’s ability to adopt these lizing an interprofessional team addressing healthy behaviours, gly- healthy behaviours is influenced by many factors, including the cemic control, blood pressure control, lipid management and social, environmental, cultural and economic conditions in which cardiovascular protection measures has been shown to effectively the individual lives (the “determinants of health”). These include and dramatically lower the risk of development and progression of income, education and literacy; employment and working condi- serious complications for individuals with diabetes (24–27) (see Car- tions; food security; environment and housing; early childhood diovascular Protection in People with Diabetes chapter, p. S162; development; social support and connectedness; and access to health Dyslipidemia chapter, p. S178; Treatment of Hypertension chapter, care (15) (see Type 1 Diabetes in Children and Adolescents chapter, p. S186; Nutrition Therapy chapter, p. S64; Physical Activity and p. S234). There is a need for governments to develop policies aimed Diabetes chapter, p. S54; Pharmacologic Glycemic Management of at addressing poverty and other systemic barriers to health care (16). Type 2 Diabetes, p. S88, Targets for Glycemic Control chapter, p. S42). In addition, individuals with diabetes must be supported in the skills of self-management since their involvement in disease manage- Ethnocultural Diversity ment is absolutely necessary for success (see Self-Management Edu- cation and Support chapter, p. S36). People with diabetes require Canada is a country rich in ethnocultural diversity. Canada boasts training in goal setting, problem solving and health monitoring, all the highest percentage of foreign-born citizens than any other G8 of which are critical components of self-management. They also need country. More than 200 ethnic origins were reported in Canada in access to a broad range of tools, including medications, devices and the 2011 census, with the most common ethnic origins with popu- supplies to help them achieve the recommended blood glucose, lipid lations in excess of 1 million from highest to lowest, including Cana- and blood pressure targets. Health outcomes depend on manag- dian, English, French, Scottish, Irish, German, Italian, Chinese, ing the disease effectively, and, without access to the necessary tools Indigenous, Ukrainian, East Indian, Dutch and Polish. The largest and strategies, Canadians living with diabetes will not be able to visible minority groups in 2011—South Asians, Chinese and Blacks achieve optimal results. All levels of government should commit to (accounting for 61.3% of the total visible minority population)— investing in chronic care management and support the tools needed are populations identified as being at high risk for diabetes; and for successful self-management to ensure that optimal care can be were followed by Filipinos, Latin Americans, Arabs, Southeast Asians, delivered. West Asians, Koreans and Japanese (17). Studies have shown that culturally appropriate diabetes education (incorporating cultural or faith traditions, values and beliefs, delivery in the person’s pre- The Diabetes Charter ferred language, adapted cultural dietary advice, the person’s needs, and/or involving family members) results in improvements in The Diabetes Charter for Canada clearly outlines the support diabetes-related knowledge, self-management behaviours and clini- Canadians with diabetes need to live to their full potential. It defines cal outcomes (18,19) (see Self-Management Education and Support the right of people with diabetes to information, education and care chapter, p. S36; see Nutrition Therapy chapter, p. S64). Given our that take into account a person’s culture and language (see Appen- diversity, Canada has much to teach the world of the importance dix 1. Diabetes Charter, p. S307). The Charter also puts forth the right of incorporating cultural traditions and health-care beliefs in dia- of people with diabetes to high quality care regardless of where they betes care with many innovative models of diabetes health-care live. The Charter notes that governments have a responsibility to delivery. As Canada’s Prime Minister Justin Trudeau has aptly stated address the unique needs and disparities in care and outcomes of “Diversity is Canada’s strength” (20). vulnerable populations who experience higher rates of diabetes and Diabetes rates are 3 to 5 times higher in Indigenous popula- complications and/or significant barriers to diabetes care and tions in Canada (7), a situation compounded by barriers to care for support. These supports will help Canadians with diabetes manage many Indigenous peoples. Indeed, the vastness of Canada poses chal- their disease and related complications. lenges in providing comprehensive and uniform diabetes care throughout the country. Indigenous people are generally diag- nosed at a younger age than non-Indigenous people (21), and Indig- Other Topics enous women experience higher rates of gestational diabetes than non-Indigenous women (22). Complications of diabetes are also Each set of Diabetes Canada Clinical Practice Guidelines has more frequently seen among the Indigenous population than in the become increasingly longer. This set of guidelines has seen the addi- non-Indigenous population (23). The chapter on type 2 diabetes and tion of material on diabetes and driving, post-transplant diabetes S4 R.L. Houlden / Can J Diabetes 42 (2018) S1–S5 and many other topics. However, it is recognized that several topics numerous studies both varied and unique. There have been huge are still not covered. Oral health is one such topic. Gingivitis, an strides and key advances in mapping and understanding the physi- inflammatory condition of the gums surrounding the teeth, and peri- ology, biochemistry and genetics of diabetes, as well as develop- odontitis, the destruction of the ligament, bone and soft tissues that ments in the prevention, treatment and management of the disease. support the teeth, are two of the most serious dental conditions iden- Key goals remain a desire to improve the quality of life of people tified in individuals with both type 1 and type 2 diabetes (28). One living with diabetes and to find a cure. study found that adults with poorly controlled diabetes had a sig- Regulatory agencies should not apply these guidelines in a rigid nificantly higher prevalence of severe periodontitis than those way with regard to clinical research in diabetes. It is suggested that without diabetes (odds ratio 2.90, 95% confidence interval 1.40– study protocols may include guideline recommendations, but indi- 6.03) (29). The pain, discomfort and eventual tooth loss associ- vidual decisions belong in the domain of the patient-physician rela- ated with these conditions can lead to poor diet, nutritional tionship. The merits of each research study must be assessed deficiencies, psychosocial problems and an overall decline in quality individually so as to not block or restrict the pursuit of new infor- of life. Periodontal disease may also increase the risk of developing mation. Diabetes Canada welcomes the opportunity to work with type 2 diabetes because the body’s inflammatory response to the regulatory agencies to enhance research in Canada and, ulti- periodontal bacteria may contribute to insulin resistance (30). In mately, to improve the care of people with diabetes. addition to gingivitis and periodontitis, individuals with diabetes have higher rates of dental caries and salivary dysfunction. The IDF has prepared guidelines on oral health for people with diabetes (31). Cost Considerations The recommendations include: people with diabetes should see a dental professional regularly for oral health check-ups; health- These clinical practice guidelines, like those published before, care providers should enquire at least annually for symptoms of gum have purposefully not taken into account cost effectiveness in the disease (including bleeding when brushing teeth, and gums which evaluation of the evidence surrounding best practice for a variety are swollen or red); and people with diabetes should be reminded of reasons, including the paucity of cost-effectiveness analyses using that daily dental care is a normal part of diabetes self-management. Canadian data; the difficulty in truly accounting for all relevant The relationship between diabetes and cancer is another topic diabetes-related costs; as well as lack of expertise and resources not reviewed in this set of guidelines. Diabetes has been consis- to perform the appropriate cost-effectiveness analyses needed for tently associated with increased risk of several of the more common all the clinical questions within the clinical practice guidelines. In cancers (32); however, it remains unclear whether the association addition, it is often difficult to philosophically judge which is of is direct (e.g. due to hyperglycemia), whether diabetes is a marker greater importance: clinical benefit for the person living with dia- of underlying biologic factors that alter cancer risk (e.g. insulin resis- betes or cost to the health-care system, as well as, at what level of tance and hyperinsulinemia), or whether the cancer-diabetes asso- cost effectiveness should one consider a therapy worth recom- ciation is indirect and due to common risk factors, such as obesity mending? Based on issues of feasibility and philosophical consid- (33). It is also not known whether diabetes treatments influence erations of our role as recommendation developers, it was decided risk of cancer or cancer prognosis. Pending further research, people that cost would not be included in the recommendations to ensure with diabetes should be encouraged to undergo appropriate cancer that they reflect the best available clinical evidence for the indi- screenings as recommended for all people in their age group and vidual with diabetes. sex (33). Dissemination and Implementation Conflict of Interest Dissemination & Implementation Committee co-chairs and The Diabetes Canada 2018 Clinical Practice Guidelines for the Pre- volunteer members were appointed at the beginning of the guide- vention and Management of Diabetes in Canada have been devel- lines process. On an ongoing basis, the committee develops strat- oped by a multidisciplinary panel of volunteer experts and informed egies to increase health-care practitioner implementation of the individuals living with diabetes based on a rigorous systematic recommendations with the goal of improving health care for the review that rates the quality of evidence and strength of recom- person with diabetes. A major activity of the committee has been mendations (see Methods chapter, p. S6). The need to incorporate the development and maintenance of a guidelines website patient preferences is also discussed throughout the document. Any (http://guidelines.diabetes.ca/) which hosts the full guidelines; discussion regarding off-label use of drugs includes the caveat that interim updates; a quick reference guide; key messages; health- the use is off-label. care provider tools, slide kits, videos and webinars; as well as An explicit and transparent process has been used to minimize resources for people with diabetes and their support systems in a biases. Experts have not received honoraria or stipends. In addi- variety of languages. Both IOS and Android apps have also been tion, a policy defining manageable or disqualifying conflict of inter- developed. est is strictly adhered to and available on request. Detailed conflict of interest statements using the International Committee of Medical Journal Editors (ICJME) disclosure form (http://www.icmje.org/) (with Conclusions the addition of government funding sources) for all members of the Expert, Steering and Executive Committees, as well as the Inde- Diabetes is a common condition with significant implications pendent Methods Review Committee, are posted publically on the for quality of life, as well as mental health and physical condi- guidelines website and updated annually for each year of the guide- tions. Although there have been a number of advances in preven- line development process (http://guidelines.diabetes.ca). tion and treatment, many individuals with diabetes have less than optimal glycemic control and are at risk for or have complica- Research tions. Given the large number of people at risk for or currently living with diabetes, as well as predictions for dramatic increases Since Banting and Best’s discovery of insulin in Toronto in 1921, in these numbers in the future, there is a need to improve preven- the scope of diabetes research in Canada has been vast and the tion and treatment strategies, particularly for vulnerable and high  R.L. Houlden / Can J Diabetes 42 (2018) S1–S5 S5 risk populations. Diabetes is also a complicated disease with a con- 10. Ohinmaa A, Jacobs P, Simpson S, et al. The projection of prevalence and cost of diabetes in Canada: 2000 to 2016. Can J Diabetes 2004;28:1–8. stantly expanding literature on new therapies and technologies that 11. Stats Can. Body composition of Canadian adults, 2009 to 2011. Ottawa, ON: Gov- makes it challenging for health-care providers who care for people ernment of Canada, Statatistics Canada; 2012. Report No.: 82-625-X. Available with or at risk for diabetes to remain up to date. These guidelines from: http://www.statcan.gc.ca/pub/82-625-x/2012001/article/11708-eng.pdf. are a celebration of the work, contributions and creativity of health- 12. Roberts KC, Shields M, de Groh M, et al. Overweight and obesity in children and adolescents: Results from the 2009 to 2011 Canadian Health Measures Survey. care providers and people living with diabetes across Canada and Ottawa, ON: Government of Canada, Statistics Canada; 2012. Report No.: contain evidence-based recommendations that provide a useful 82-003-X. Available from: http://www.statcan.gc.ca/pub/82-003-x/2012003/ reference tool to help health-care providers translate the best avail- article/11706-eng.pdf. 13. Dinca-Panaitescu S, Dinca-Panaitescu M, Bryant T, et al. Diabetes prevalence and able evidence into clinical practice as well as for people with dia- income: Results of the Canadian Community Health Survey. 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Following the process used to develop previous Diabetes Canada Guidelines based on biological or mechanistic reasoning, Clinical Practice Guidelines (1), an Executive Committee, Steering expert opinion or consensus had to be explicitly identified and Committee and Expert Committee with broad expertise and geo- graded as such; harmonization was sought with other Cana- graphic representation were assembled. In total, 135 volunteers, from dian guideline bodies, including the Canadian Cardiovascular diverse practice settings across the country, including profession- Society (CCS), Hypertension Canada and the Canadian Cardio- als from family medicine, endocrinology, internal medicine, cardi- vascular Harmonization of National Guidelines Endeavour ology, neurology, nephrology, infectious disease, urology, psychiatry, (C-CHANGE). psychology, obstetrics, ophthalmology, pediatrics, nursing, dietet- ics, pharmacy, chiropractic, exercise physiology, and others, par- ticipated in the guideline development process. Identifying and Appraising the Evidence To further support the principles previously adopted to develop evidence-based recommendations, the current iteration of the guide- “The trials we have comprise islands of evidence, linked by shorter lines engaged the McMaster Evidence Review and Synthesis Centre and longer bridges of extrapolation spanning oceans of uncertainty... to systematically search, review and perform a critical appraisal of The longer the bridge and the farther we are from an island, the the literature. An online database (2) was used to enhance within shakier the extrapolation... and across chapter communication and documentation of the review More good outcomes trials means more islands, shorter bridges and of the literature, and to create guideline “memory” for future itera- less uncertainty... tions of Diabetes Canada Clinical Practice Guidelines. Elements But there will always be an ocean to span and a bridge to cross.” covered by the Appraisal of Guidelines for Research and Evalua- (Hertzel Gerstein, 2015) tion (AGREE) II instrument were incorporated into the guideline Authors for each chapter were assembled based on their rel- development process (3). evant fields of expertise. Each chapter had 1 lead author, 1 or 2 “evi- dence resource” persons trained or experienced in clinical Each recommendation had to address a clinically important epidemiology or clinical research methodology, and up to 6 addi- question related to 1 or more of the following: detection, prog- tional authors, as needed. At the outset of the process, committee nosis, prevention or management of diabetes and its sequelae. members from each section of the guidelines attended a work- Health benefits, risks and side effects of interventions were con- shop on evidence-based practice and guideline development, in order sidered in formulating the recommendations. Patient prefer- to ensure a consistent approach to the development of recommen- ences and values were sought from expert panel members living dations. Committee members identified clinically important ques- with diabetes and the literature (where available). tions related to diagnosis, prognosis, prevention and treatment of Whenever possible, each recommendation had to be justified diabetes and its complications, which were used as a basis for our by the strongest clinically relevant, empirical evidence that could literature search strategy (outlined below). be identified; the citation(s) reporting this evidence had to be Authors were to explicitly define: a) the population to which noted adjacent to the relevant guideline. the question would apply; b) the test, risk factor or intervention The strength of this evidence, based on prespecified criteria from being addressed; c) an appropriate reference standard or control the epidemiologic literature and other guidelines processes, had population to which the test, intervention or exposure was to be to be noted (4–9). compared; and d) the clinically relevant outcomes being targeted. Each recommendation had to be assigned a grade based on the This information was used to develop specific, clinically relevant available evidence, its methodological strength and its appli- questions that were the focus of literature searches. For each cability to the Canadian population. question, strategies were developed combining diabetes terms Each recommendation was reviewed by an Independent with methodological terms. Two health sciences librarians with Methods Review member and had to be approved by the expertise in evidence-based practice constructed and peer-reviewed comprehensive searches of the relevant English-language, pub- lished, peer-reviewed literature using validated search strategies of Conflict of interest statements can be found on page S9. electronic databases (MEDLINE, EMBASE, CINAHL, the Cochrane 1499-2671 © 2018 Canadian Diabetes Association. The Canadian Diabetes Association is the registered owner of the name Diabetes Canada. https://doi.org/10.1016/j.jcjd.2017.10.002  D. Sherifali et al. / Can J Diabetes 42 (2018) S6–S9 S7 Central Register of Trials, and PsycINFO [where appropriate]). For Table 1 topics that were covered in the 2013 Clinical Practice Guidelines, Criteria for assigning levels of evidence to the published studies the literature searches focused on new evidence published since Level Criteria those guidelines, including literature published in September 2013 Studies of diagnosis or later. For new topics, the search time frame included the litera- Level 1 a) Independent interpretation of test results (without ture published since 1990 or earlier where relevant. Updated lit- knowledge of the result of the diagnostic or gold erature searches were performed at two other intervals throughout standard) b) Independent interpretation of the diagnostic the development process. standard (without knowledge of the test result) Once citation duplicates were removed, all references and full- c) Selection of people suspected (but not known) to text documents were loaded into DistillerSR (2). Using a priori have the disorder defined criteria of inclusion and exclusion, all citations were screened d) Reproducible description of both the test and diagnostic standard at the title and abstract level in duplicate by team members from e) At least 50 patients with and 50 patients without the evidence centre; full-text screening was completed by a dia- the disorder betes clinician and methodologist for relevance. All full-text cita- Level 2 Meets 4 of the Level 1 criteria tions and supporting documents were then made available to the Level 3 Meets 3 of the Level 1 criteria Level 4 Meets 1 or 2 of the Level 1 criteria chapter authors for review. Authors were asked to review all remain- ing citations and systematically determine whether the citation Studies of treatment and prevention would be used for background material, discarded (with justifica- Level 1A Systematic overview or meta-analysis of high-quality RCTs tion) or used to support a new or existing recommendation. Each a) Comprehensive search for evidence citation that was used to formulate, update or revise a recommen- b) Authors avoided bias in selecting articles for dation was critically appraised using standardized tools for treat- inclusion ment, diagnostic or prognostic studies with built-in algorithms to c) Authors assessed each article for validity ensure consistent approaches to generating levels of evidence, based d) Reports clear conclusions that are supported by the data and appropriate analyses on prespecified criteria in Table 1. The level of evidence was then OR determined by the cited paper’s objectives, methodological rigour, Appropriately designed RCT with adequate power to susceptibility to bias and generalizability (Table 1). Because they answer the question posed by the investigators could not be critically appraised, meeting abstracts, narrative review a) Patients were randomly allocated to treatment groups articles, news reports and other sources could not be used to support b) Follow up at least 80% complete recommendations. Papers evaluating the cost effectiveness of thera- c) Patients and investigators were blinded to the pies or diagnostic tests also were not included. Finally, citation flow treatment* diagrams depicting the search, review and selection of citations for d) Patients were analyzed in the treatment groups to each chapter, specifically, the number of citations reviewed, removed which they were assigned e) The sample size was large enough to detect the and requiring new or revised recommendations, are included at the outcome of interest end of each chapter (10). Level 1B Non-randomized clinical trial or cohort study with A number of considerations were made when evaluating the evi- indisputable results dence within a given area. For example, people with diabetes are Level 2 RCT or systematic overview that does not meet Level 1 criteria at high risk for several sequelae that are not exclusive to diabetes Level 3 Non-randomized clinical trial or cohort study; (e.g. cardiovascular disease, renal failure and erectile dysfunc- systematic overview or meta-analysis of level 3 tion). As such, some evidence relating to these problems was iden- studies tified that either excluded, did not report on or did not focus on Level 4 Other people with diabetes. Whenever such evidence was identified, a level Studies of prognosis was assigned using the approach described above. Higher levels were Level 1 a) Inception cohort of patients with the condition of assigned if: a) people with diabetes comprised a predefined sub- interest, but free of the outcome of interest group; b) the results in the diabetes subgroup were unlikely to have b) Reproducible inclusion/exclusion criteria c) Follow up of at least 80% of subjects occurred by chance; and c) the evidence was generated in response d) Statistical adjustment for extraneous prognostic to questions that were formulated prior to the analysis of the results. factors (confounders) Lower levels (than those indicated in Table 1) were assigned to evi- e) Reproducible description of outcome measures dence that did not meet these criteria. Level 2 Meets criterion a) above, plus 3 of the other 4 criteria Level 3 Meets criterion a) above, plus 2 of the other criteria Level 4 Meets criterion a) above, plus 1 of the other criteria * In cases where such blinding was not possible or was impractical (e.g. inten- Guideline Development sive vs. conventional insulin therapy), the blinding of individuals who assessed and adjudicated study outcomes was felt to be sufficient. Expert Committee members evaluated the relevant literature, RCT, randomized controlled trial. and guidelines were developed and initially reviewed by the Expert Committee. In the absence of new evidence since the publication cited in the final recommendation and were assigned a grade to of the 2013 Clinical Practice Guidelines, recommendations from the reflect the uncertainty signalled by conflicting findings. Further 2013 document were not changed. details on the grading process are described below. The studies used to develop and support each recommenda- Finally, several treatment recommendations were based on evi- tion are cited beside the level of evidence. In some cases, key cita- dence generated from the use of 1 therapeutic agent from a given tions that influenced the final recommendation were not assigned class (e.g. 1 of the “statins”). Whenever evidence relating to 1 or the same level of evidence, but rather were of varying levels of evi- more agents from a recognized class of agents was available, the dence. In those circumstances, all relevant studies were cited, regard- recommendation was written so as to be relevant to the class, but less of the grading assigned to the recommendation. The final grading specifically studied therapeutic agents were identified within the depended on the totality of evidence, including the relative strengths recommendation and/or cited reference(s). Only medications with of the studies from a methodological perspective and the studies’ Health Canada Notice of Compliance granted by September 15, 2017 findings. Studies with conflicting outcomes were considered and were included in the recommendations. S8 D. Sherifali et al. / Can J Diabetes 42 (2018) S6–S9 Table 2 evidence may be impossible, impractical or too expensive to gen- Criteria for assigning grades of recommendations for clinical practice erate (which implies that it would be impossible to develop Grade Criteria Grade A recommendations). Varying grades of recommendations, Grade A The best evidence was at Level 1 therefore, reflect varying degrees of certainty regarding the strength Grade B The best evidence was at Level 2 of inference that can be drawn from the evidence in support of the Grade C The best evidence was at Level 3 recommendation. Therefore, these evidence-based guidelines and Grade D The best evidence was at Level 4 or consensus their graded recommendations are designed to satisfy 2 impor- tant needs: 1) the explicit identification of the best research upon which the recommendation is based, and an assessment of its sci- entific relevance and quality (captured by the assignment of a level Grading the Recommendations of evidence to each citation); and 2) the explicit assignment of strength of the recommendation based on this evidence (cap- After formulating new recommendations or modifying exist- tured by the grade). In this way, they provide a convenient summary ing ones based on new evidence, each recommendation was assigned of the evidence to facilitate clinicians in the task of “weighting” and a grade from A through D (Table 2). The highest possible grade that incorporating ever-increasing evidence into their daily clinical a recommendation could have was based on the strength of evi- decision-making. They also facilitate the ability of clinicians, health- dence that supported the recommendation (i.e. the highest level care planners, health-care providers, and society, in general, to criti- of evidence assigned to studies on which the recommendation was cally examine any recommendation and arrive at their own based). However, the assigned grading was lowered in some cases; conclusions regarding its appropriateness. Thus, these guidelines for example, if the evidence was found not to be applicable to the facilitate their own scrutiny by others according to the same prin- Canadian population or, if based on the consensus of the Steering ciples that they use to scrutinize the literature. and Executive Committees, there were additional concerns regard- It is important to note that the system chosen for grading rec- ing the recommendation. In some situations, the grading also was ommendations differs from the approach used in some other guide- lowered for subgroups that were not well represented in the study, line documents in which a treatment or procedure that is not useful/ or in whom the beneficial effect of an intervention was less clear. effective and in some cases may be harmful are assigned a grade Grading also was lowered if the findings from relevant (and equally or class (11). In this Diabetes Canada guidelines document, recom- rigorous) studies on the topic were conflicting. Thus, a recommen- mendation to avoid any harmful practices would be graded in the dation based on Level 1 evidence, deemed to be very applicable to same manner as all other recommendations. However, it should be Canadians and supported by strong consensus, was assigned a grade noted that the authors of these guidelines focused on clinical prac- of A. A recommendation not deemed to be applicable to Canadi- tices that were thought to be potentially beneficial, and did not seek ans, or judged to require further supporting evidence, was assigned out evidence regarding the harmfulness of interventions. a lower grade. Where available, the number of patients that would need to be treated in order to prevent 1 clinical event (number needed to treat [NNT]) or to cause an adverse event (number needed Independent Methodological Review to harm [NNH]) was considered in assessing the impact of a par- ticular intervention. The degree to which evidence derived from other An Independent Methods Review (IMR) committee was estab- populations was felt to be relevant to diabetes also was reflected lished to ensure consistency and rigour in the recommendation in the wording and grading of the recommendation. Finally, in the development process. The IMR consisted of 9 university-based cli- absence of Level 1, 2 or 3 supporting evidence, or if the recom- nician faculty with advanced training in research methods (2 mendation was based on the consensus of the Steering and Execu- co-chairs, and 7 reviewing members). The IMR provided method- tive Committees, the highest grade that could be assigned was D. ological expertise and were a resource available to the recommen- dation authors throughout the development process. All drafted recommendations and their supporting evidence were Interpreting the Assigned Grade of a Recommendation appraised and graded by the recommendation authors. The IMR would then provide a secondary critical review of the recommen- The grade assigned to each recommendation is closely linked dation and the evidence to ensure the following: 1) There was strong to the methodological rigour and robustness of the relevant clini- fidelity between the wording of the recommendation and the cited cal research. Therefore, as noted above, a high grade reflects a high clinical evidence; and 2) Provide an independent appraisal and grade degree of confidence that following the recommendation will lead for the cited evidence. Where appropriate, the IMR would suggest to the desired outcome. Similarly, a lower grade reflects weaker evi- rephrasing of recommendations to ensure the recommendation dence, and a greater possibility that the recommendation will change accurately reflected the underpinning evidence. In the event that when more evidence is generated in the future. Of note, the assigned there was discordance between the author-assigned grade and the grade contains no subjective information regarding the impor- IMR-assigned grade, the recommendation was arbitrated by 1 of tance of the recommendation or how strongly members of the com- the IMR co-chairs. All IMR review activities were systematically per- mittee felt about it; it contains information regarding only the formed and recorded to ensure procedural quality and transparency. evidence upon which the recommendation is based. Thus, many Grade D recommendations were deemed to be very important to the contemporary management of diabetes, based on clinical expe- External Peer Review rience, case series, physiological evidence and current concepts of disease pathophysiology. However, the paucity of clinical evi- In May 2017, a draft document was circulated nationally and dence addressing the areas of therapy, prevention, diagnosis or prog- internationally for content review by numerous stakeholders nosis precluded the assignment of a higher grade. and experts in relevant fields, including specialists, community Clearly, clinicians need to base clinical decisions on the best avail- primary care providers, academic departments of family medicine able relevant evidence that addresses clinical situations. However, across Canada, and specialty and disease support organizations. This they also frequently are faced with having to act in the absence of input was then considered by the Expert, Executive and Steering clinical evidence, and there are many situations where good clinical Committees and revisions were made accordingly. Revised  D. Sherifali et al. / Can J Diabetes 42 (2018) S6–S9 S9 recommendations were reviewed and approved by the Executive Novo Nordisk, and Eli Lilly, outside the submitted work. Dr. Rabi and Steering Committees. Selected recommendations were pre- does not have anything to disclose. sented at a professional and public forum at the Diabetes Canada/ Canadian Society of Endocrinology and Metabolism Professional Conference and Annual Meetings in Edmonton, Alberta on Novem- References ber 4, 2017. 1. Canadian Diabetes Association Clinical Practice Guideline Expert Committee. Canadian Diabetes Association 2013 clinical practice guidelines for the preven- tion and management of diabetes in Canada. Can J Diabetes 2013;37:S1–212. Disclosure of Conflict of Interest 2. Evidence Partners. Distiller (DistillerSR systematic review software) [com- puter program]. Ottawa: Evidence Partners, 2017. 3. Brouwers M, Kho ME, Browman GP, et al. Appraisal of guidelines for research Expert Committee members were volunteers and received no & evaluation II. AGREE II instrument. Canadian Institute for Health Research remuneration or honoraria for their participation. Members of all com- (CIHR), 2013. 4. Straus SE, McAlister FA. What is the prognosis? In: Gerstein HC, Haynes RB, eds. mittees signed an annual duality of interest form listing all finan- Evidence-based diabetes care. Hamilton: BC Decker Inc., 2001, pg. 6–12. cial interests or relationships with manufacturer(s) of any commercial 5. Guyatt G, Rennie D, Meade MO, et al., eds. Users’ guides to the medical litera- product(s) and/or provider(s) of commercial services. The most recent ture: A manual for evidence-based clinical practice. 3rd edn. New York: McGraw- Hill, 2015. 2018 disclosures have been included at the end of each chapter. Duali- 6. Jaeschke R, Guyatt GH. How should diagnostic test be chosen and used? In: ties of interest were discussed during deliberations where relevant. Gerstein HC, Haynes RB, eds. Evidence-based diabetes care. Hamilton: BC Decker In the case of a potential duality or outright conflict of interest, com- Inc., 2001, pg. 13–23. 7. Holbrook AM, Clarke J-A, Raymond C, et al. How should a particular problem mittee members removed themselves from discussions. be managed? Incorporating evidence about therapies into practice. In: Gerstein HC, Haynes RB, eds. Evidence-based diabetes care. Hamilton: BC Decker Inc., 2001, pg. 24–47. 8. Harris SB, Webster-Bogaert SM. Evidence-based clinical practice guidelines. In: Other Relevant Guidelines Gerstein HC, Haynes RB, eds. Evidence-based diabetes care. Hamilton: BC Decker Inc., 2001, pg. 48–61. Introduction, p. S1 9. Goldbloom R, Battista RN. The periodic health examination: 1. Introduction. CMAJ 1986;134:721–3. 10. Moher D, Liberati A, Tetzlaff J, et al. Preferred reporting items for systematic reviews and meta-analyses: The PRISMA statement. PLoS Med 2009;6:e1000097. Author Disclosures 11. Ryden L, Grant PJ, Anker SD, et al. ESC Guidelines on diabetes, pre-diabetes, and cardiovascular diseases developed in collaboration with the EASD: The Task Force on diabetes, pre-diabetes, and cardiovascular diseases of the European Society Dr. Sherifali reports investigator-initiated funding from of Cardiology (ESC) and developed in collaboration with the European Asso- AstraZeneca. Dr. Houlden reports grants from Boehringer Ingelheim, ciation for the Study of Diabetes (EASD). Eur Heart J 2013;34:3035–87.  Can J Diabetes 42 (2018) S10–S15 Contents lists available at ScienceDirect Canadian Journal of Diabetes journal homepage: w w w. c a n a d i a n j o u r n a l o f d i a b e t e s. c o m 2018 Clinical Practice Guidelines Definition, Classification and Diagnosis of Diabetes, Prediabetes and Metabolic Syndrome Diabetes Canada Clinical Practice Guidelines Expert Committee Zubin Punthakee MD, MSc, FRCPC, Ronald Goldenberg MD, FRCPC, FACE, Pamela Katz MD, FRCPC “Prediabetes” is a practical and convenient term referring to KEY MESSAGES impaired fasting glucose (IFG), impaired glucose tolerance (IGT) (1) or a glycated hemoglobin (A1C) of 6.0% to 6.4%, each of which places The chronic hyperglycemia of diabetes is associated with significant long- individuals at high risk of developing diabetes and its complications. term microvascular and cardiovascular complications. A fasting plasma glucose of ≥7.0 mmol/L, a 2-hour plasma glucose value in a 75 g oral glucose tolerance test of ≥11.1 mmol/L or a glycated hemo- globin (A1C) of ≥6.5% can predict the development of retinopathy. This Classification of Diabetes permits the diagnosis of diabetes to be made on the basis of each of these parameters. The majority of cases of diabetes can be broadly classified into The term “prediabetes” refers to impaired fasting glucose, impaired glucose tolerance or an A1C of 6.0% to 6.4%, each of which places individuals at 2 categories: type 1 diabetes and type 2 diabetes, although some increased risk of developing diabetes and its complications. cases are difficult to classify. Gestational diabetes (GDM) refers to glucose intolerance with onset or first recognition during preg- nancy. The classification of diabetes is summarized in Table 1. Appendix 2 addresses the etiologic classification of diabetes, includ- KEY MESSAGES FOR PEOPLE WITH DIABETES ing less common forms associated with genetic mutations, dis- eases of the exocrine pancreas (such as cystic fibrosis), other diseases There are 2 main types of diabetes. Type 1 diabetes occurs when the pan- or drug exposure (such as glucocorticoids, medications to treat HIV/ creas is unable to produce insulin. Type 2 diabetes occurs when the pan- AIDS, and atypical antipsychotics). creas does not produce enough insulin or when the body does not effectively Monogenic diabetes is a rare disorder caused by genetic defects use the insulin that is produced. of beta cell function that typically presents in young people (