IMPACT OF LOW BODY MASS INDEX ON CORONARY ATHEROSCLEROSIS: MULTIVESSEL ANGIOSCOPIC STUDY

Abstract

Although a low body mass index (BMI) is pointed out to be an increased long term risk of cardiovascular events, there is no evidence that the association of BMI levels and the degree of coronary angioscopic assessment of atherosclerosis. We evaluated and compared the degrees of coronary atherosclerosis using multivessel angioscopy; further, we also examined the relationship between the levels of BMI and the cumulative incidence of cardiovascular events with 10-year follow-up. We retrospectively analyzed consecutive 89 coronary artery disease patients who underwent angioscopic observation of multiple coronary arteries. The patients were divided into four different BMI categories: underweight < 20 kg/m2 (n=7); normal weight 20 to < 25 kg/m2 (n=40); over weight 25 to 28 kg/m2 (n=15). We examined the frequencies of plaque rupture, coronary thrombus, and yellow plaque. Furthermore, we followed all patients for newly cardiovascular events. The severity of coronary atherosclerosis were significantly different in the 4 groups by the number of yellow plaques (NYP) per vessel (2.10 ± 1.16 vs. 1.53 ± 0.91 vs. 1.33 ± 0.79 vs. 1.10 ± 0.93, p=0.024 for trend) and the maximum yellow grade (MYG) (2.57 ± 0.54 vs. 2.25 ± 0.87 vs. 1.96 ± 0.90 vs. 1.93 ± 1.03, p=0.046 for trend). The graded regression of BMI levels was associated with the higher prevalence of multiple (>2) yellow plaques in one coronary artery (MYP) (p=0.016 for trend), and increased cumulative incidences of cardiovascular events (p=0.024 for trend). Univariate logistic analysis revealed BMI level, diabetes, and serum LDL-C level to be predictors for MYP. These 3 variables were not attenuated in multivariate analysis (BMI: odds ratio [OR], 0.82; 95% CI, 0.70-0.97; p=0.017, diabetes: OR, 4.86; 95% CI, 1.38-17.1; p=0.014, LDL-C: OR, 1.03; 95% CI, 1.01-1.05; p=0.002). The coronary atherosclerosis evaluated by angioscopy in underweight patients was more advanced than normal and overweight patients. A low BMI was independently related to advanced coronary atherosclerosis and increased risk of cardiovascular events.