Abstract 1473: Central Obesity and Cardiovascular Outcomes in Patients With Acute Coronary Syndromes: Observations From the MERLIN-TIMI 36 Trial
Despite the association of obesity with a greater prevalence of other CV risk factors and incident events, the obesity paradox has been consistently observed in ACS. However, the timing of this paradox and the role of more metabolically-active central obesity has not been explored in ACS. We investigated the effect of two markers of obesity, body mass index (BMI) and waist circumference (WC), on outcomes after NSTE-ACS.
METHODS: 6496 patients with NSTE-ACS who had BMI or WC determined at presentation in the MERLIN-TIMI 36 trial were followed for 1 year (median=348 days). Patients were stratified into 3 BMI groups (<25, 25–30, >30 kg/m2) and tertiles of WC (<96, 96 –106, >106 cm). Multivariable analysis, adjusting for sex and the TIMI risk score, was performed to examine the relation between BMI and WC on an endpoint of CV death, MI, or severe recurrent ischemia.
RESULTS: Those with BMI 25–30 and BMI >30 had a lower risk of the endpoint (HR 0.81, p=0.049; HR 0.63, p<0.0001) at 30 days. When BMI groups were stratified by WC, there was a trend towards worse outcomes in higher WC groups within lower BMI groups (Fig-L⇓). The group with the lowest BMI and highest WC had the highest risk (HR 3.33, p=0.032). After the acute phase, landmark analysis from 30d to 1 yr showed no difference in risk between BMI groups after the first 30 days (Fig-R⇓).
CONCLUSIONS: Obesity is associated with more favorable short-term outcomes after ACS, however, in the long-term, the obesity paradox reverses. Notably, within the lowest BMI group, those with increased WC were at high risk, implying a risk associated with central adiposity. Central obesity may better stratify individuals at increased risk following ACS as compared to BMI.