Plasma levels of plant sterols and the risk of coronary artery disease: the prospective EPIC-Norfolk Population Study

Some studies have suggested that a modest increase of plant sterol levels is a risk factor for coronary artery disease (CAD). We studied the relationship between plant sterol levels and CAD risk in a prospective nested case-control study consisting of 373 cases and 758 controls. Sitosterol and campesterol concentrations did not differ between cases and controls [sitosterol, 0.21 vs. 0.21 mg/dl (P = 0.1); campesterol, 0.31 vs. 0.32 mg/dl (P = 0.5)]. The sitosterol-to-cholesterol ratio was significantly lower in cases than in controls (1.19 vs. 1.29 μg/mg; P = 0.008), whereas the campesterol-to-cholesterol ratio did not differ significantly (1.78 vs. 1.88 μg/mg; P = 0.1). Plant sterol concentrations correlated positively with cholesterol levels and inversely with body mass index and triglyceride and lathosterol concentrations. Among individuals in the highest tertile of the sitosterol concentration, the unadjusted odds ratio (OR) for future CAD was 0.75 [95% confidence interval (CI) = 0.56–1.01]. After adjustment for traditional risk factors, the OR was 0.79 (95% CI = 0.56–1.13). For the campesterol concentration, the unadjusted OR was 0.95 (95% CI = 0.71–1.29) and the adjusted OR was 0.97 (95% CI = 0.68–1.39). In this large prospective study, higher levels of plant sterols, at least in the physiological range, do not appear to be adversely related to CAD in apparently healthy individuals.