Abstract 481: Coronary Calcium Scores Are Lower 5 Years After Bariatric Surgery: Evidence for Slowed Progression of Atherosclerosis?
Background: Coronary artery calcium (CAC) is a marker of atherosclerosis and is strongly predictive of cardiovascular events. Obesity is a risk factor for higher CAC scores and cardiovascular events. Our objective is to evaluate the effect of gastric bypass surgery (GBS) on CAC scores.
Methods: The Utah Obesity Study is a prospective registry of 1156 severely obese subjects, ~30% of whom underwent GBS. We performed a CT scan of the heart and abdomen in 136 consecutive subjects returning for 5-year follow up. CAC scores (Agatston method) and visceral adipose tissue volumes were calculated by two blinded investigators.
Results: Baseline characteristics and CAD risk factors were similar between the groups except for slightly lower age and systolic blood pressure in the GBS group (Table 1⇓). At 5 years, CAC scores, weight, and visceral adipose volumes were significantly lower in patients who underwent GBS than those without surgery (Table 2⇓). Additionally, GBS subjects were more likely to have a CAC score of zero independent of gender, age, smoking, systolic blood pressure, and LDL cholesterol (OR = 2.3, p = 0.045).
Conclusions: Subjects who underwent GBS had markedly lower CAC scores and were more likely to have a CAC score of zero than the nonsurgical group, independent of traditional risk factors for coronary artery disease. These findings raise the intriguing possibility that bariatric surgery may slow the progression of coronary atherosclerosis. Moreover, this occurs by mechanisms that appear to be at least partially independent of traditional risk factors.