Abstract P097: Consumption of Branched Chain Amino Acids and Risk of Coronary Heart Disease in US Men and Women

Background Plasma concentrations of branched chain amino acids (BCAAs; valine, leucine, and isoleucine) have recently been associated with risk factors for coronary heart disease (CHD), including obesity and type 2 diabetes. Diet is the only source of these essential amino acids in humans. However, it is unknown whether dietary BCAA intake is associated with risk of CHD. Methods and Results The present study included 74,275 women and 44,421 men from two prospective cohorts: the Nurses’ Health Study (NHS) and Health Professionals Follow-up Study (HPFS) who were free of diagnosed cardiovascular disease, diabetes or cancer at baseline. We documented 3,060 incident CHD events (including nonfatal myocardial infarction and fatal CHD) during 24 years follow-up of the NHS and 4,128 incident CHD events during 22 years follow-up of the HPFS. BCAA intake was calculated by summing intakes of valine, leucine, and isoleucine estimated from food frequency questionnaires obtained every 4 years. After adjustment for age, ethnicity, smoking, physical activity, alcohol consumption, family history of myocardial infarction, history of hypertension and hypercholesterolemia, aspirin use, menopausal status (women only), glycemic load, intakes of total energy, cereal fiber, fruits, vegetables, saturated fat, polyunsaturated fat and trans fat, BCAA intake was significantly associated with increased risk of CHD in women (for highest vs lowest quintiles of BCAA intake, hazard ratio [HR] = 1.40 [95% CI 1.21-1.62]; P for trend <0.001), men (HR = 1.15 [1.02-1.29]; P for trend =0.01) and combined by meta-analysis (HR = 1.24 [1.13-1.36]; P for trend <0.001). Adjustment for body mass index and diabetes status attenuated the association but the result remained significant in the combined samples (HR = 1.13 [1.04-1.24] for highest vs lowest quintiles of BCAA intake; P for trend =0.008). In separate analyses, intakes of individual BCAA (leucine, isoleucine, and valine) were each associated with increased risk of CHD. Conclusions Our data suggest that higher consumption of BCAAs is associated with moderately increased risk of CHD in women and men and the association is partly explained by obesity and diabetes status.