Long-term effects of in-hospital cardiac rehabilitation on the cardiac risk profile: A case-control study in pairs of siblings with myocardial infarction

Aims: In the general population, measures for secondary prevention of myocardial infarction are poorly utilized. Our aim was therefore to analyse whether post-myocardial infarction in-hospital rehabilitation and education programmes improve the subsequent utilization of preventive strategies. Methods and Results: We screened 93 500 patient charts in cardiac rehabilitation clinics to identify a myocardial infarction patient with a sibling, who likewise had a myocardial infarction prior to the age of 60 years but was discordant with respect to the participation in cardiac in-hospital rehabilitation. In 92 such sibling pairs the coronary risk profile was studied by standardized questionnaire, biochemical measurements and physical examination. At the time of the acute myocardial infarction, both groups showed an equal risk factor distribution. However, at follow-up (on average 5.5 years after myocardial infarction), rehabilitation-siblings presented with significantly lower systolic (137 ± 2 vs 150 ± 3 mmHg, P<0·01) and diastolic blood pressure (82 ± 1 vs 89 ± 1 mmHg, P<0·01). Antihypertensive drug therapy resulted more often in effective (≤140/90 mmHg) control of blood pressure (58% vs 29%, P<0·01). Blood lipid levels and smoking prevalence tended to be lower in rehabilitation-siblings. Significantly fewer rehabilitation-siblings presented with two or more modifiable risk factors (OR 0·36 (CI 0·17-0·76); P<0·01). There was a strong tendency towards fewer recurrent cardiac events (re-myocardial infarction, coronary angioplasty, coronary artery bypass grafting) during follow-up in rehabilitation-siblings (OR 0·57 (CI 0·31-1·04); P=0·07). Conclusion: An in-hospital programme for cardiac rehabilitation may successfully encourage therapy to modify risk factors and thus enhance the long-term implementation of secondary prevention.