Serum Fatty Acids and the Risk of Stroke

Abstract
Background and Purpose To examine the relationship between serum fatty acids, which reflect dietary intake, and stroke, we conducted a nested case-control study of 96 men with incident stroke and 96 control subjects matched by age, clinical center, treatment group, and date of randomization who were enrolled in the Multiple Risk Factor Intervention Trial. Methods After confirming the stability of the stored serum samples, we measured serum cholesterol ester and phospholipid fatty acid levels as the percentage of total fatty acids by gas-liquid chromatography and examined their association with incident stroke. Using stepwise conditional logistic regression that controlled for risk factors for stroke, we determined which fatty acids were independent correlates of stroke. Results In univariate models, a standard deviation (SD) increase (1.37%) in phospholipid stearic acid (18:0) was associated with a 37% increase in the risk of stroke, whereas an SD increase (0.06%) in phospholipid ω-3 α-linolenic acid (18:3) was associated with a 28% decrease in the risk of stroke (all P <.05). Only α-linolenic acid in the cholesterol ester fraction was associated with the risk of stroke in multivariate models: an SD increase (0.13%) in the serum level of α-linolenic acid was associated with a 37% decrease in the risk of stroke ( P <.05). Systolic blood pressure and cigarette smoking were also independently associated with stroke risk. Conclusions Our findings suggest that higher serum levels of the essential fatty acid α-linolenic acid are independently associated with a lower risk of stroke in middle-aged men at high risk for cardiovascular disease.