Impact of Duration in a Cardiac Rehabilitation Program on Coronary Risk Profile and Health-Related Quality of Life Outcomes

Abstract

BACKGROUND: Optimal cardiac rehabilitation (CR) program length and the time course of changes in relevant outcomes are unknown. The purpose of this study was to assess changes in coronary risk factors and health-related quality of life (HRQoL) after 3 months and 6 months of cardiac rehabilitation. METHODS: This is an observational study of a cohort of 126 consecutive cardiac rehabilitation patients who completed baseline, 3-month, and 6-month evaluations of coronary risk factors and HRQoL. The coronary risk factors included lipid profile, blood pressure, body mass index (BMI), and physical activity level. HRQoL was assessed using the Short Form-36 questionnaire (SF-36) comprising eight health concepts and two component scales (physical [PCS] and mental [MCS]). RESULTS: There was significant improvement in all coronary risk factors and HRQoL measures, except BMI, over the 6-month period (P < 0.001). Significant changes in blood pressure, physical activity, PCS, and high-density lipoprotein cholesterol (HDL-C) were apparent at 3 months, and no additional significant changes in these variables occurred between 3 and 6 months. For total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and MCS, significant change was achieved between 3 and 6 months but not between baseline and 3 months. CONCLUSIONS: Secondary prevention and HRQoL outcomes improved at variable rates. Physical activity and physical function peaked at 3 months and were maintained at program completion. Significant improvements occurred in mental health recovery beyond the traditional 12-week CR program length. Outcomes furthest from normative values showed the most rapid improvement. Optimal duration of participation may vary according to the outcome of interest.