Long-term Prevention of Mortality in Morbid Obesity Through Bariatric Surgery. A Systematic Review and Meta-analysis of Trials Performed With Gastric Banding and Gastric Bypass
Bariatric surgery has been reported to reduce long-term mortality in operated participants in comparison with nonoperated participants.Methods:
We performed a systematic review and meta-analysis of clinical trials published as full articles dealing with cardiovascular (CV) mortality, all-cause mortality (noncardiovascular), and global mortality (sum of CV and all-cause mortality). Pooled-fixed effects of estimates of the risk of mortality in participants undergoing surgery were calculated compared with controls.Results:
Of 44,022 participants from 8 trials (14,052 undergoing surgery and 29,970 controls), death occurred in 3317 participants (400 in surgery, 2917 in controls); when the kind of death was specified, 321 CV deaths (118 in surgery, 203 in controls), and 523 all-cause deaths (218 in surgery, 305 in controls) occurred. Compared with controls, surgery was associated with a reduced risk of global mortality (OR = 0.55, CI, 0.49–0.63), of CV mortality (OR = 0.58, CI, 0.46–0.73), and of all-cause mortality (OR = 0.70, CI, 0.59–0.84).Conclusion:
This meta-analysis indicates that (1) bariatric surgery reduces long-term mortality; (2) risk reduction is smaller in large than in small studies; and (3) both gastric banding and gastric by-pass reduce mortality with a greater effect of the latter on CV mortality.