Comparative outcome one year after formal cardiac rehabilitation: the effects of a randomized intervention to improve exercise adherence

BACKGROUND: Methods to ensure sustained benefits of cardiac rehabilitation need to be explored. The aim was to assess the effect of a home-based intervention (INT) on exercise adherence and risk factors after cardiac rehabilitation. DESIGN: Prospective randomized study. METHODS: We evaluated patients who were followed for 1 year after either inpatient (ICR) or outpatient cardiac rehabilitation (OCR) by assessment of exercise capacity, physical activity, risk factors and quality of life, both at the completion of rehabilitation, and after 1 year. Patients were randomized to either be instructed how to use a diary of physical activities complemented by quarterly group meetings (INT) or to receive standard treatment (usual care). RESULTS: Two hundred and sixty-one patients gave consent to be reevaluated after 1 year. Of these patients 33 were lost to follow-up (two deaths); thus 228 patients had complete 1-year follow-up data (195 male and 33 female, 91% with coronary artery disease). At 1-year follow-up significantly more patients of the INT group than of the control group adhered to regular physical activity (73 vs. 40%, P<0.0001). Moreover, INT patients showed a better evolution of body mass index and lipid values. In a stepwise multiple regression analysis the following variables showed a significant impact on regular physical activity at follow-up: study INT odds ratio (OR): 4.19, P<0.0001, previous cardiac surgery (OR: 2.50, P=0.008), BMI at baseline (OR: 0.89, P=0.018) and quality of life at baseline (OR: 1.58, P=0.041). CONCLUSION: Sustained benefits of cardiac rehabilitation can be documented 1 year after both inpatient and outpatient programmes. Self-monitoring of physical activity greatly increased long-term adherence to regular exercise, which in turn was associated with greater improvements of risk factors and quality of life.