Deranged fat metabolism and the lowering effect of carbohydrate-poor diet on serum triglycerides in patients with chronic renal failure

Effects of fish oil rich in eicosapentaenoic acid on serum lipid in hyperlipidemic hemodialysis patients

The incidence of atherosclerosis in hemodialysis (HD) patients is very high. Major risk factors are aging, lipid metabolism disturbances, high blood pressure, and smoking. High blood pressure and hypertriglyceridemia, which is atherogenic in the presence of smoking, are encountered very often in HD patients. The effects of eicosapentaenoic acid (EPA) on plasma lipids and blood pressure were studied for the first time in HD patients by the administration of capsules containing fish oil rich in EPA, which is known to lower serum lipid concentration and blood pressure. We treated 12 hyperlipidemic patients (3 of type IIa, 3 of type IIb, and 6 of type IV; 3 males, 9 females; 31 to 70 years of age; 4 to 90 months on HD) with 24 capsules (1.6 g EPA and 1.0 g docosahexaenoic acid) per day for 13 weeks. Serum triglycerides, total cholesterol, and phospholipid decreased significantly after capsule administration. The ratio of EPA to arachidonic acid in serum increased significantly. There was a small but statistically significant decrease in platelet count. Diastolic blood pressure decreased at the end of the experiment. These effects of fish oil are considered favorable for the prevention of atherosclerosis and its subsequent diseases.

[Fat and renal failure--therapeutic aspects]

There is current debate as to whether or not the hyperlipidaemia seen in patients (1) with chronic renal insufficiency, (2) on regular dialysis treatment and (3) after successful renal transplantation should be specifically treated. The reduced HDL cholesterol fraction suggests that the risk of cardiovascular complications may be increased. Therapeutic possibilities include increased physical exercise and a reduction of carbohydrate intake. If these measures fail, then treatment with clofibrate or bezafibrate should be considered. The recommended dosage of clofibrate is 1.0-1.5 g/week (with CPK-control), and of bezafibrate is 400-500 mg/week in patients with chronic renal insufficiency (creatinin-clearance below 20 ml/min). In patients on regular dialysis treatment plasma lipids are reduced by adding carnitine. Most investigators believe that a specific therapy of the hypercholesterolaemia and hypertriglyceridaemia of patients with nephrotic syndrome is not necessary since the disturbances in fat metabolism are associated with an increased levels of HDL-cholesterol. With remission of the nephrotic syndrome an improvement of the hyperlipoproteinaemia is observed. If patients with acute renal failure are under parenteral nutrition fat infusion is recommended once per week to avoid a deficiency of essential fatty acids which is augmented by daily dialysis therapy.