Coronary heart disease risk factors before and after bypass surgery: results of a controlled trial on multifactorial rehabilitation

The effect of a three-phase multfactorial institution-based rehabilitation programme on coronary heart disease (CHD) risk factors was studied in an open randomised trial comprising 228 patients undergoing coronary artery bypass surgery allocated into a rehabilitation (R) group (n = 119) anda hospital (H = control) group (n = 109). Follow-up examinations were performed at 6 and 12 months. Serum total cholesterol and triglyceride levels decreased significantly in both groups during follow-up. These decreases were not significantly dfferent between the R and H groups. Serum high density lipoprotein (HDL) cholesterol level increased significantly at 6 and 12 months in the R group, but not in the H group. The differences in the changes between the groups were not significant. The ratio of serum HDL cholesterol to total cholesterol increased significantly in the R group from the preoperative value of 0.154 to 0.179 (P <0.001) at 6 months and to 0.180 (P<0.001) at 12 months. In the H group these values were 0.152, 0.166 (P<0.001) and 0.168 (P<0.001), respectively. The significance of the differences in the changes between the groups were P = 0.01 at 6 months and 0.06 at 12 months. These dfferences were more obvious in patients aged 55 years or under. There was a signficant decrease (P=0.005) in the proportion of smokers in the R group and a significant increase in the proportion of patients taking regular exercise in both groups as assessed by questionnaire. No changes in blood pressure were observed. The results suggest that favourable changes in serum lipids can be achieved by well organised after-care of patients undergoing coronary artery bypass surgery. The additional benefit from institution-based multifactorial rehabilitation is a greater increase in the ratio of HDL cholesterol to total cholesterol. This effect is more marked in young patients.