Nicholas L Syn1, David E Cummings2, Louis Z Wang3, Daryl J Lin4, Joseph J Zhao4, Marie Loh5, Zong Jie Koh6, Claire Alexandra Chew6, Ying Ern Loo4, Bee Choo Tai7, Guowei Kim6, Jimmy Bok-Yan So6, Lee M Kaplan8, John B Dixon9, Asim Shabbir10. 1. Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Biostatistics & Modelling Domain, Saw Swee Hock School of Public Health, Singapore. 2. UW Medicine Diabetes Institute, Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, and Weight Management Program, Veteran Affairs Puget Sound Health Care System, University of Washington, Seattle, WA, USA. 3. Yong Loo Lin School of Medicine, National University of Singapore, Singapore; SingHealth Internal Medicine Residency Programme, Singapore General Hospital, Singapore. 4. Yong Loo Lin School of Medicine, National University of Singapore, Singapore. 5. Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK; Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore. 6. Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Surgery, University Surgical Cluster, National University Health System, Singapore. 7. Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Biostatistics & Modelling Domain, Saw Swee Hock School of Public Health, Singapore; Saw Swee Hock School of Public Health, National University of Singapore and National University Health System, Singapore. 8. Obesity, Metabolism and Nutrition Institute and Department of Medicine, Division of Gastroenterology, Massachusetts General Hospital, Boston, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA, USA. 9. Iverson Health Innovation Research Institute, Swinburne University of Technology, Melbourne, VIC, Australia. 10. Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Surgery, University Surgical Cluster, National University Health System, Singapore. Electronic address: cfsasim@nus.edu.sg.
Abstract
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.
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.
Authors: Mustafa Bektaş; Beata M M Reiber; Jaime Costa Pereira; George L Burchell; Donald L van der Peet Journal: Obes Surg Date: 2022-06-17 Impact factor: 3.479
Authors: Darren Jun Hao Tan; Cheng Han Ng; Phoebe Wen Lin Tay; Nicholas Syn; Mark D Muthiah; Wen Hui Lim; Ansel Shao Pin Tang; Kai En Lim; Grace En Hui Lim; Nobuharu Tamaki; Beom Kyung Kim; Margaret Li Peng Teng; James Fung; Rohit Loomba; Mindie H Nguyen; Daniel Q Huang Journal: JAMA Netw Open Date: 2022-06-01
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