Effects of apolipoprotein E phenotype on serum cholesterol level and cholesterol response to diet therapy in patients...

We investigated the association of the apolipoprotein (apo) E isoform phenotype with the basal serum cholesterol level and cholesterol response to diet therapy in outpatients with primary hypercholesterolemia. The basal levels of serum cholesterol, triglyceride and HDL-cholesterol in the 132 subjects were 286 +/- 26 mg/dl, 154 +/- 83 mg/dl and 54 +/- 14 mg/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 phenotypes, 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 of 52 participants before and 2-3 months after diet therapy. After dietary counselling, serum cholesterol values were reduced significantly from 293 +/- 27 to 256 +/- 36 mg/dl (P < 0.01) in the total group of study subjects. There was no significant difference in serum cholesterol reduction 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 > or = 1.0) exhibited a greater reduction in serum 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 investigators have suggested that apo E phenotypes influence the response of serum cholesterol to dietary changes.