Bariatric surgery as a model for obesity research. Nick Finer BSc, FRCP, FAfN University College London UK

Transcription

1 Bariatric surgery as a model for obesity research Nick Finer BSc, FRCP, FAfN University College London UK

2 Defining the problem - what do we know and what has been achieved (greatest achievements)? Obesity treatment aims to achieve long-term weight loss maintenance with health improvement and risk reduction Lifestyle interventions: many lose weight but few maintain >3% weight loss beyond 18 months Pharmacotherapy: a logical adjunct to lifestyle intervention but so far drugs have poor efficacy:safety or cost benefit Bariatric surgery: reliably produces durable and substantial weight loss with large reductions in adverse clinical outcomes (reduced mortality, cardiovascular events and diabetes resolution)

3 Weight Loss and Remission of diabetes after bariatric surgery Gastric Banding Gastric Bypass Sleeve Gastrectomy Duodenal Switch 50 % EWL 65% EWL 65% EWL 75% EWL 57% 80% 80% 95% EWL=Excess Weight Loss Buchwald H, Oien DM. Metabolic/bariatric surgery Worldwide Obes Surg 2009;19:

4 Cardiovascular and cancer (women) mortality after bariatric surgery Sjostrom et al. JAMA. 2012;307(1): Sjostrom et al. Lancet Oncol 2009; 10:

5 Yearly increase in publications on Bariatric Surgery *

6 Knowledge gaps concerning bariatric surgery: how does it produce weight loss, health improvement and lower mortality? Original hypotheses of restriction and malabsorption of energy not the main causes Weight loss: early and enhanced satiation induced by Gut peptide hormones including reduced ghrelin, increased PYY, GLP-1 Afferent vagal nerve pathways Diabetes: Enhanced incretin axis Decreased visceral/pancreatic fat Caloric restriction Exclusion of foregut Bile acids Gut microbiota

7 Knowledge gaps concerning bariatric surgery: Intervention research Understanding variation in response to treatment Matching treatment to patient need Phenotyping Benefits and risks at lower thresholds of BMI in South Asian people with diabetes RCTs against standard therapies for co-morbidities e.g. Diabetes, obstructive sleep apnoea Complications of care Role of co-morbidities Role and timing in childhood/adolescence Adapted from Canadian Institutes of Health Research. accessed 12 th Feb 2012

8 Knowledge gaps concerning bariatric surgery: Health Services and Health Policy Research Understanding optimal systems of care focused on continuity of care (i.e., Cradle to grave) Medical/surgical/rehabilitation/mental health/self-care Primary care, including collaborative models and intervention strategies for practitioner and practice change Understanding what brings people to treatment and what are the major barriers, including gender differences Evaluation of wait-list management strategies and decision rules for access to bariatric surgery Forecasting models based on need and demand analyses and projections Adapted from Canadian Institutes of Health Research. accessed 12 th Feb 2012

9 What are the research potentials for bariatric surgery? A tool to understand actions of, and synergies between, appetite regulation hormones that reliably produces weight loss maintenance allowing research into effects of weight loss on clinical and psychological parameters and outcomes to understand the influence of genotype on outcomes to understand epigenetic influences of maternal (and paternal) obesity to aid development of pharmacological mimetics to drive development of endoluminal approaches and devices

10 What societal impact might the outcomes of this research have? Configuration of health care commissioning/purchasing to meet demand for surgery and long-term follow-up Shifts of budgets (e.g. from type 2 diabetes and respiratory silos ) to provision of bariatric surgery Increasing numbers of pregnancies in women who have had bariatric surgery Possible unintended consequences of a cure reducing individual efforts to maintain healthy weight

11 How can we develop new products (technical, pharmaceutical or processual) from the outcomes of this research? Peptide hormones (alone or in combination) as pharmaceutical agents Nutriceuticals influencing gut microbiota Endoluminal and other devices