EFFECTS OF APOLIPOPROTEIN-E PHENOTYPE ON SERUM-CHOLESTEROL LEVEL AND CHOLESTEROL RESPONSE TO DIET THERAPY IN PATIENTS WITH HYPERCHOLESTEROLEMIA

We investigated the association of the apolipoprotein (apo) E isoform phenotype with the basal serum cholesterol level and cholesterol respo nse to diet therapy in outpatients with primary hypercholesterolemia. The basal levels of serum cholesterol, triglyceride and HDL-cholestero l in the 132 subjects were 286+/-26 mg/dl, 154+/-83mg/dl and 54+/-14 m g/dl, respectively. The frequencies of apo E 3/2, 3/3, 4/2, 4/3 and 4/ 4 were 1, 104, 2, 24 and 1, respectively. There were no differences in serum lipids between subjects with the two most common apo E phenotyp es, i.e., apoE 3/3 (n=104) and apoE 4/3 (n=24). The serum cholesterol response to diet therapy was evaluated by measuring the serum lipids o f 52 participants before and 2-3 months after diet therapy. After diet ary counselling, serum cholesterol values were reduced significantly f rom 293+/-27 to 256+/-36 mg/dl (P<0.01) in the total group of study su bjects. There was no significant difference in serum cholesterol reduc tion in response to diet therapy between subjects with apoE4 (E4/2, E4 /3 and E4/4, n=12) and without apoE4 (E3/3 and E3/2, n=40). Following dietary counselling, patients who lost a large amount of body weight ( BM I greater than or equal to 1.0) exhibited a greater reduction in se rum cholesterol than those who showed less weight loss. In conclusion, the results of our study demonstrated the primary importance of diet therapy in the treatment of hypercholesterolemia, although other inves tigators have suggested that apo E phenotypes influence the response o f serum cholesterol to dietary changes.