Randomized controlled trial of gamma-linolenic acid and eicosapentaenoic acid in peripheral arterial disease

Background and Aims: epidemiological studies suggest polyunsaturated fatty acids protect against the development of atherosclerosis. The aim of this s tudy was to perform a randomized controlled trial of gamma-linolenic and ei cosapentaenoic acids in patients with lower limb atherosclerosis. Main outc ome measures were: cholesterol and lipoprotein concentrations; haemostatic and rheological variables; the ankle brachial pressure index; walking dista nce; and cardiovascular events and death. Methods: 120 men and women with stable intermittent claudication were rando mized to 2 years treatment with either a combination of gamma-linolenic and eicosapentaenoic acids, or placebo. Results: 39 (65.0%) of those taking fatty acids and 36 (60.0%) of those tak ing placebo completed the trial. Lipid concentrations did not differ signif icantly during the trial. In those taking fatty acids, haematocrit was sign ificantly higher than in the placebo group after 6 months (46.1% compared w ith 44.6%, P less than or equal to 0.01), and systolic blood pressure was s ignificantly lower after 2 years (150 mmHg compared with 161.8 mmHg, less t han or equal to 0.05). There was no difference in walking distance, but the re was a small reduction in non-fatal coronary events in the fatty acid gro up (10% compared with 15%, P > 0.05). Conclusions: a combination of polyunsaturated fatty acids produced a statis tically significant reduction in systolic blood pressure, but no other sign ificant benefits on risk factors. The trend towards fewer coronary events i n those taking fatty acids warrants further investigation.