Arginine intake, blood pressure, and the incidence of acute coronary events in men: the Kuopio Ischaemic Heart Disease Risk Factor Study.

BACKGROUND Evidence suggests that dietary supplementation of L-arginine, the precursor of nitric oxide, may protect arteries against atherosclerosis. OBJECTIVE We tested the hypothesis that dietary arginine intake is associated with a decreased risk of acute coronary events in Finnish men aged 42-60 y. DESIGN We investigated this association in a prospective cohort study of men who were free of prior coronary artery disease and who were examined in 1984-1989 in the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD). The dietary arginine intake of 1981 men was assessed by a 4-d food intake record during the baseline phase of the KIHD. RESULTS Men in the highest quintile of dietary arginine intake (>or= 5691 mg/d) did not have a significantly lower risk of acute coronary events than did men in the 4 lower quintiles (relative risk after adjustment for potential coronary risk factors: 1.28; 95% CI: 0.85, 1.94). The covariates were age; examination years; body mass index; systolic blood pressure; serum total, HDL, and LDL cholesterol; serum triacylglycerols; urinary excretion of nicotine metabolites; maximal oxygen uptake in an exercise test; and alcohol intake. Splitting arginine intake into deciles or analyzing plant- and animal-derived arginine separately did not show any association between dietary arginine intake and the risk of acute coronary events. Arginine intake was also not consistently associated with blood pressure. CONCLUSION Dietary arginine intake is not associated with the risk of acute coronary events in middle-aged men in eastern Finland.