Long-Term Cardiovascular Outcomes After Bariatric Surgery in the Medicare Population

Background: The long-term effect of bariatric surgery on cardiovascular outcomes in the elderly population is not well studied. Objectives: The aim of this study was to evaluate the association between bariatric surgery and long-term cardiovascular outcomes in the Medicare population. Methods: Medicare beneficiaries who underwent bariatric surgery from 2013 to 2019 were matched to a control group of patients with obesity with a 1:1 exact matching based on age, sex, body mass index, and propensity score matching on 87 clinical variables. The study outcomes included all-cause mortality, new-onset heart failure (HF), myocardial infarction (MI), and ischemic stroke. An instrumental variable analysis was performed as a sensitivity analysis. Results: The study cohort included 189,770 patients (94,885 matched patients in each group). By study design, the 2 groups had similar age (mean: 62.33 ± 10.62 years), sex (70% female), and degree of obesity (mean body mass index: 44.7 ± 7.3 kg/m²) and were well balanced on all clinical variables. After a median follow-up of 4.0 years (IQR: 2.4-5.7 years), bariatric surgery was associated with a lower risk of mortality (9.2 vs 14.7 per 1,000 person-years; HR: 0.63; 95% CI: 0.60-0.66), new-onset HF (HR: 0.46; 95% CI: 0.44-0.49), MI (HR: 0.63; 95% CI: 0.59-0.68), and stroke (HR: 0.71; 95%: CI: 0.65-0.79) (P < 0.001). The benefit of bariatric surgery was evident in patients who were 65 years and older. Using instrumental variable analysis, bariatric surgery was associated with a lower risk of mortality, HF, and MI. Conclusions: Among Medicare beneficiaries with obesity, bariatric surgery is associated with lower risk of mortality, new-onset HF, and MI.