Centile Charts for Monitoring of Weight Loss Trajectories After Bariatric Surgery in Asian Patients.

BACKGROUND: Following bariatric surgery, accurate charting of weight loss and regain is crucial. Various preoperative factors affect postoperative weight loss, including age, sex, ethnicity, and surgical type. These are not considered by current weight loss metrics, limiting comparison of weight loss outcomes between patients or centers and across time. METHODS: Patients (n=1022) who underwent sleeve gastrectomy (n=809) and gastric bypass (n=213) from 2008 to 2020 in a single center were reviewed. Weight loss outcomes (% total weight loss) were measured for 60 months postoperatively. Longitudinal centile lines were plotted using the post-estimation predictions of quantile regression models, adjusted for type of procedure, sex, ethnicity, and baseline BMI. RESULTS: Median regression showed that %TWL was 1.0% greater among males than females (ß = +1.1, 95% CI: +0.6 to +1.7, P = <0.0001). Participants who underwent SG had less %TWL compared to GB (ß = -1.3, 95% CI: -1.9 to -0.8, P < 0.0001). There was a trend towards less %TWL among the Indian and Malay participants compared to Chinese. Age and diabetes were not significant predictors. Reference centile charts were produced for the overall cohort, as well as specific charts adjusted for type of bariatric procedure, sex, ethnicity, and baseline BMI. CONCLUSION: Centile charts provide a clinically relevant method for monitoring of weight trajectories postoperatively and aid in realistic and personalised goal setting, and the early identification of "poor responders". This is the first study to present post-bariatric surgery centile charts for an Asian cohort.

Association of metabolic-bariatric surgery with long-term survival in adults with and without diabetes: a one-stage meta-analysis of matched cohort and prospective controlled studies with 174 772 participants.

BACKGROUND: Metabolic-bariatric surgery delivers substantial weight loss and can induce remission or improvement of obesity-related risks and complications. However, more robust estimates of its effect on long-term mortality and life expectancy-especially stratified by pre-existing diabetes status-are needed to guide policy and facilitate patient counselling. We compared long-term survival outcomes of severely obese patients who received metabolic-bariatric surgery versus usual care. METHODS: We did a prespecified one-stage meta-analysis using patient-level survival data reconstructed from prospective controlled trials and high-quality matched cohort studies. We searched PubMed, Scopus, and MEDLINE (via Ovid) for randomised trials, prospective controlled studies, and matched cohort studies comparing all-cause mortality after metabolic-bariatric surgery versus non-surgical management of obesity published between inception and Feb 3, 2021. We also searched grey literature by reviewing bibliographies of included studies as well as review articles. Shared-frailty (ie, random-effects) and stratified Cox models were fitted to compare all-cause mortality of adults with obesity who underwent metabolic-bariatric surgery compared with matched controls who received usual care, taking into account clustering of participants at the study level. We also computed numbers needed to treat, and extrapolated life expectancy using Gompertz proportional-hazards modelling. The study protocol is prospectively registered on PROSPERO, number CRD42020218472. FINDINGS: Among 1470 articles identified, 16 matched cohort studies and one prospective controlled trial were included in the analysis. 7712 deaths occurred during 1·2 million patient-years. In the overall population consisting 174 772 participants, metabolic-bariatric surgery was associated with a reduction in hazard rate of death of 49·2% (95% CI 46·3-51·9, p<0·0001) and median life expectancy was 6·1 years (95% CI 5·2-6·9) longer than usual care. In subgroup analyses, both individuals with (hazard ratio 0·409, 95% CI 0·370-0·453, p<0·0001) or without (0·704, 0·588-0·843, p<0·0001) baseline diabetes who underwent metabolic-bariatric surgery had lower rates of all-cause mortality, but the treatment effect was considerably greater for those with diabetes (between-subgroup I2 95·7%, p<0·0001). Median life expectancy was 9·3 years (95% CI 7·1-11·8) longer for patients with diabetes in the surgery group than the non-surgical group, whereas the life expectancy gain was 5·1 years (2·0-9·3) for patients without diabetes. The numbers needed to treat to prevent one additional death over a 10-year time frame were 8·4 (95% CI 7·8-9·1) for adults with diabetes and 29·8 (21·2-56·8) for those without diabetes. Treatment effects did not appear to differ between gastric bypass, banding, and sleeve gastrectomy (I2 3·4%, p=0·36). By leveraging the results of this meta-analysis and other published data, we estimated that every 1·0% increase in metabolic-bariatric surgery utilisation rates among the global pool of metabolic-bariatric candidates with and without diabetes could yield 5·1 million and 6·6 million potential life-years, respectively. INTERPRETATION: Among adults with obesity, metabolic-bariatric surgery is associated with substantially lower all-cause mortality rates and longer life expectancy than usual obesity management. Survival benefits are much more pronounced for people with pre-existing diabetes than those without. FUNDING: None.