Electrocardiographic events and cholesterol reduction with pravastatin in patients with hypercholesterolemia: the Hokuriku Lipid Coronary Heart Disease Study-Pravastatin Atherosclerosis Trial

Background: Cholesterol lowering therapy may offset the development of coronary atherosclerosis, and the resulting reduction in coronary ischemia may be observed in the electrocardiogram (ECG). Methods: A total of 2039 Japanese adults with hypercholesterolemia were divided into two groups (receiving 10-20 mg pravastatin daily or a normal diet) and were followed up for 5 years. ECG studies were performed at entry and every year during the follow-up period. The occurrence of myocardial infarction and the appearance or worsening of ischemic ST changes were assessed in terms of effects on the ECG. Results: Of the 2039 patients registered, 827 were excluded from the study for various reasons. Consequently, a total of 1212 patients were analyzed. There was a lower degree of worsening in the pravastatin group (n=757) than in the normal diet group (n=455) in the primary prevention cohort [11 (1.8%) vs. 16 (4.3%), respectively, P=0.031]. On the other hand, there was no difference in the frequency of worsening between the two groups in the secondary prevention cohort [7 (4.4%) in the pravastatin group vs. 4 (4.9%) in the diet group, P=0.25]. Event-free survival was better in the pravastatin group than in the normal diet group in the primary prevention cohort (P=0.011), but there was no difference between the two groups in the secondary prevention cohort. Conclusions: These results suggest that pravastatin may reduce the incidence of coronary heart disease and that this effect may be predominantly observed in patients with early atheromatous lesions.