Abstract 13262: Phytosterol Intake and Risk of Coronary Heart Disease in U.S. Men and Women

Abstract

Introduction: Phytosterols are structurally similar to cholesterol and partially inhibit intestinal absorption of cholesterol. Evidence regarding dietary phytosterols in relation to coronary heart disease (CHD) risk remains limited. We aimed to prospectively assess the associations between total and individual phytosterol intake and CHD risk in U.S. men and women. Methods: A total of 214,108 men and women from the Nurses’ Health Study (NHS), NHSII, and Health Professionals Follow-Up Study without cardiovascular disease or cancer at baseline were included in the analyses. Diet was assessed using a validated food frequency questionnaire every 2-4 years since baseline. Cox proportional hazards regression models were used to evaluate associations between phytosterol intake and CHD risk. Results: During 5,516,455 person-years of follow-up, 10,152 CHD cases were documented. Comparing extreme quintiles, pooled hazard ratios (HRs) (95% CIs) of CHD were 0.91 (0.85-0.98; P -trend=0.08) for total phytosterols, 0.88 (0.82-0.95; P -trend=0.02) for campesterol, 0.96 (0.90-1.02; P -trend=0.22) for stigmasterol, and 0.91 (0.84-0.98; P -trend=0.03) for beta-sitosterol. Nonlinear associations were observed for total phytosterols, campesterol, and beta-sitosterol: the risk reduction plateaued at intakes above ~180 mg/day, 30 mg/day, and 130 mg/day, respectively ( P -nonlinearity<0.001). Among 23,543 participants with existing CHD risk markers, phytosterol intake was inversely associated with plasma levels of total cholesterol, triglycerides, C-reactive protein, and interleukin-6, and was positively associated with adiponectin. Phytosterol intake was not associated with LDL or HDL cholesterol levels. Conclusions: Higher long-term intake of total and major subtypes of phytosterols was associated with modest CHD risk reduction, which may plateau at moderate intake levels. The role of phytosterols in preventing CHD needs further investigation.