UCLA

AIMS: Studies have suggested relationships between obesity and cardiovascular disease (CVD) morbidity. However, little is known about whether substantial weight reduction affects the risk of CVD-related acute care use in obese patients with CVD. The objective of this study was to determine whether bariatric surgery is associated with decreased risk of CVD-related acute care use. METHODS AND RESULTS: We performed a self-controlled case series study of obese adults with CVD who underwent bariatric surgery, using population-based emergency department (ED), and inpatient samples in California, Florida, and Nebraska from 2005 to 2011. The primary outcome was ED visit or unplanned hospitalization for CVD. We used conditional logistic regression to compare the risk during sequential 12-month periods, using pre-surgery months 13-24 as the reference period. We identified 11 106 obese adults with CVD who underwent bariatric surgery. During the reference period, 20.6% [95% confidence interval (CI), 19.8-21.3%] of patients had an ED visit or unplanned hospitalization for CVD. The risk did not significantly change in the subsequent 12-month pre-surgery period [adjusted odds ratio (aOR) 0.98; 95% CI, 0.93-1.04; P = 0.42]. By contrast, in the first 12-month period after bariatric surgery, the risk significantly decreased (aOR 0.91; 95% CI, 0.86-0.96; P = 0.002). The risk remained reduced in the subsequent 13-24 months post-bariatric surgery (aOR 0.84; 95% CI, 0.79-0.89; P < 0.001). There was no reduction in the risk in separate obese populations that underwent non-bariatric surgery (i.e. cholecystectomy, hysterectomy). By CVD category, the risk of acute care use for coronary artery disease (CAD), heart failure (HF), and hypertension decreased after bariatric surgery, whereas that of dysrhythmia and venous thromboembolism transiently increased (Bonferroni corrected P < 0.05 for all comparisons). CONCLUSION: Bariatric surgery is associated with a lower risk of overall CVD-related ED visit or unplanned hospitalization. The decline was mainly driven by reduced risk of acute care use for CAD, HF, and hypertension after bariatric surgery.