RCSI Obesity Lecture 2025 PDF

RCSI Royal College of Surgeons in Ireland Coláiste Ríoga na Máinleá in Éirinn Obesity: An overview of definitions, determinants, comorbidities, assessment and treatments Class Enter Yearsubtitle Two MedhereStudents (24pt, Arial Regul...

RCSI Royal College of Surgeons in Ireland Coláiste Ríoga na Máinleá in Éirinn Obesity: An overview of definitions, determinants, comorbidities, assessment and treatments Class Enter Yearsubtitle Two MedhereStudents (24pt, Arial Regular) Bahrain Module Enter ENDOBdate: 25.06.13 Course PHHD Lecturer Dr Sally Doherty Date 18th January 2025  Learning Outcomes 1. Define obesity 2. Identify determinants of obesity (Biological, Environmental, Behavioural) 3. Discuss obesity assessment for pediatric and adult patients 4. Identify the associations between obesity and physical and mental health 5. Discuss the stigma around obesity and weight bias 6. Describe treatments for obesity and their benefits 1. Define Obesity Obesity – the patient’s perspective https://www.youtube.com/watch?v=Hmisx2vyYIM&feature=youtu.be 4  Obesity Definition: Obesity is a complex chronic disease, characterised by dysfunctional or excess body fat (adiposity), that impairs health However, due to individual differences in body composition, body fat distribution and function, the threshold to which adiposity impairs health is highly variable among adults The causes of obesity are complex and result from interactions between genetic, biological, behavioural, psychosocial and environmental factors Bluher M. Adipose tissue dysfunction contributes to obesity related metabolic diseases. Best Pract Res Clin Endocrinol Metab 2013; http://apps.who.int/bmi/index.jsp?introPage=intro_3.html  2. Identify determinants of obesity (Biological, Environmental, Behavioural)  Causes of obesity: Genetic? Genetic: Size appears to run in families There is substantial evidence for the heritability of obesity, and research in both rare and common forms of obesity has identified genes with significant roles in its aetiology Twin studies: Identical twins reared apart very similar in weight - heritability ratio of approx. 70% Adopted children’s BMI related to biological parents; not related to BMI of adoptive parents ( Morrison and Bennet p.59) Research now focusing on Epigenetics – BUT – environmental factors can mediate this relationship Walley et al. Genetics of obesity and the prediction of risks for health. Human Molecular Genetics. 2006;15:R124-R130  Causes of obesity: Genetic Improving adherence to healthy dietary patterns as assessed by the Alternate Healthy Eating Index 2010 and Dietary Approach to Stop Hypertension (DASH) and Alternate Mediterranean Diet (AMED), which focuses on a Mediterranean dietary can counteract part of gene related, long term weight gain People at high genetic risk for obesity are more susceptible to the beneficial effect of improving diet quality on weight loss This underlines the importance of improving adherence to healthy dietary patterns in the prevention of weight gain, especially in people with greater genetic predisposition to obesity Wang et al. BMJ. 2018; http://www.bmj.com/content/bmj/360/bmj.j5644.full.pdf Factors contributing to the Obesogenic Environment http://www.unce.unr.edu/publications/files/hn/2010/fs1011.pdf Mackenbach et al, 2014 “Obesogenic” environment - level of fat across population too high relative to average activity levels 3. Discuss obesity assessment for pediatric and adult patients But……BMI is not the full picture BMI does not take the following into consideration: Age Gender Body frame As well as considering BMI we need to consider: Waist circumference Ratio of hip to waist Fat deposited around the abdomen Waist circumference more useful than BMI alone in characterising CVD risk Pediatric assessment of obesity BMI is an accepted tool for evaluating overweight and obesity in children, but used with caution due to the same limitations as adult BMI Three common obesity classification systems (WHO 2007, CDC 2000, Cole-IOTF), but still vary in how they classify overweight and obesity: – Example: WHO 2007 classifies overweight as weight for height >1 SD above the median of the WHO reference growth standard, while CDC 2000 classifies it as BMI ≧ 85th percentile