PLASMA ESSENTIAL FATTY-ACIDS, CIGARETTE-SMOKING, AND DIETARY ANTIOXIDANTS IN PERIPHERAL ARTERIAL-DISEASE - A POPULATION-BASED CASE-CONTROL STUDY

The aim of this study was to determine the levels of plasma fatty acid s in patients with peripheral arterial disease and in control subjects and to identify whether any risks of disease related to these differe nces were influenced by smoking and antioxidant intake. A random sampl e of 1592 men and women aged 55 to 74 years was selected from the gene ral population (the Edinburgh Artery Study), from which 153 cases of p eripheral arterial disease were identified by the presence of intermit tent claudication and low ankle systolic pressures at rest and during reactive hyperemia; these were matched by age and sex to 153 control s ubjects with no evidence of cardiovascular disease. In 113 case and 12 2 control subjects, fatty acid levels were measured in three plasma fr actions (triglyceride, cholesteryl ester, and phospholipid), and smoki ng habits and dietary antioxidant intake were determined by questionna ire. Arachidonic acid, eicosapentaenoic acid, docosahexaenoic acid, an d docosapentaenoic acid (DPA/n-3) were significantly lower in the case s than controls (P<.01). More case than control subjects were current or exsmokers (86% versus 50%; P<.001), and the case subjects had lower vitamin C intake (64.8 mg versus 71.1 mg; P<.05). By logistic regress ion adjustment for smoking and vitamin C intake, only DPA/n-3 (odds ra tio, 0.19; P<.01) and arachidonic acid (odds ratio, 0.44; P<.05) remai ned significantly related to disease; only DPA/n-3 reduced the risk as sociated with smoking. We conclude that in subjects with peripheral ar terial disease compared with healthy control subjects, the largest dif ferences occurred in fatty acids of the n-3 series, particularly DPA/n -3. Some of the adverse effects associated with smoking may therefore be partly mediated by differences in essential fatty acid metabolism. (Arterioscler Thromb. 1994;14:471 478.)