Abstract T P138: Effect Of Weight Loss Surgery On Cardiovascular Death, Nonfatal Myocardial Infarction, Or Nonfatal Stroke In Overweight And Obese Post-menopausal Women

Abstract

Background: Weight loss surgery has been used for various indications but the effects of such surgery on cardiovascular events remain understudied. Methods: We analyzed the data from Women's Health Initiative (WHI) observational study. The participants in the observational study were 93,676 women aged 50-79 years who were recruited from September 1994 to December 1998, with annual follow-up through August 14, 2009 (an average of 8 years). Cox proportional hazards analysis was used to examine the modifying effect of weight loss surgery (entered as an interaction) on the relationship between baseline body mass index categorized into various obesity groups and the outcome of total cardiovascular disease defined as cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke. Results: Weight loss surgery occurred in 42 (0.2%) of the 25406 participants who were overweight, obese or morbidly obese at baseline evaluation. Weight loss surgery was performed over a mean period (month’s ±SD) of 38.0 ±3.2 from baseline assessment. The cumulative endpoint of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke was seen in 3 of 42 and 1191 of 25364 participants who did or did not undergo weight loss surgery, respectively (p=0.5). In the multivariate analysis, weight loss surgery (interaction term p=0.6) modified the relationship between categories of obesity and cardiovascular endpoint (relative risk 1.1, 95% confidence interval 1.0 -1.1, p=0.02), after adjusting for age/gender, hypertension, diabetes mellitus, cigarette smoking, and hyperlipidemia. Conclusions: We did not observe any significant effect of weight loss surgery on reduction of cardiovascular endpoint of death, nonfatal myocardial infarction, or nonfatal stroke.