Effects of bariatric surgery on cardiovascular-related acute care use in patients with hypertrophic cardiomyopathy.

AIMS: Prior studies have suggested causal relationships between obesity and acute cardiovascular events. It has been also known that the risk of acute cardiovascular events is reduced by bariatric surgery. However, little is known about whether bariatric surgery lowers the risk of acute cardiovascular events in patients with obesity and hypertrophic cardiomyopathy (HCM). In this context, we aimed to investigate whether bariatric surgery is associated with a reduced risk of cardiovascular-related acute care use in patients with HCM. METHODS AND RESULTS: In this population-based study, the bariatric surgery group consisted of patients with HCM who underwent bariatric surgery from January 2004 to December 2014. The control group included those who have obesity and HCM and received non-bariatric elective intra-abdominal surgery during the same period. The outcome was cardiovascular-related acute care use (i.e. emergency department (ED) visits or unplanned hospitalizations for cardiovascular disease) during a 1-year post-surgery period. We used the SPARCS database, a population-based ED and inpatient database in New York State. We constructed logistic regression models with generalized estimating equations to compare the risk of the outcome events during sequential 6-month post-surgery periods. We adjusted for age, sex, number of ED visits and hospitalizations for cardiovascular disease within 2 years before the index surgery, and the Elixhauser co-morbidity measures. We also performed propensity score (PS)-matching and inverse probability treatment weighting analyses using these variables. The analytic cohort consisted of 207 adults with obesity and HCM, including 147 patients who underwent bariatric surgery and 60 in the control group. The risk was not significantly different in the 1-6 months post-surgery period. By contrast, in the 7-12 months post-surgery period, the risk of cardiovascular-related acute care use was significantly lower in the bariatric surgery group (adjusted odds ratio 0.23; 95% CI 0.068-0.71; P = 0.01) compared with the control group. In the PS-matched cohort, there were no significant differences in the baseline characteristics. The PS-matched analysis demonstrated lower risk of the outcome event in the bariatric surgery group in the 7-12 months post-surgery period. The inverse probability treatment weighting analysis replicated the findings. CONCLUSIONS: Bariatric surgery was associated with a lower risk of cardiovascular-related acute care use in the 7-12 months post-surgery period in this population-based study.