Impact of clinical and sociodemographic patient characteristics on the outcome of cardiac rehabilitation in older patients

BACKGROUND: Cardiac rehabilitation (CR) seeks to simultaneously improve several outcome parameters related to patient risk factors, exercise capacity and subjective health. A single score, the multiple outcome criterion (MOC), comprised of alterations in 13 outcome variables was used to measure the overall success of CR in an older population. As this success depends on the older patient's characteristics at the time of admission to CR, we attempted to determine the most important influences.

METHODS: The impact of baseline characteristics on the success of CR, measured by MOC, was analysed using a mixed model for 1,220 older patients (70.9 ± 7.0 years, 78.3 % men) who enrolled in 12 CR clinics. A multitude of potentially influential baseline patient characteristics was considered including sociodemographic variables, comorbidity, duration of hospital stay, exercise capacity, cardiovascular risk factors, emotional status, and laboratory and echocardiographic data.

RESULTS: Overall, CR was successful, as indicated by the mean value of the MOC (0.6 ± 0.45; min -1.0, max 2.0; positive values denoting improvement, negative ones deterioration). Examples of association with negative MOC values included smoking (MOC -0.15, p < 0.001), female gender (MOC -0.07, p = 0.049), and a longer hospital stay (MOC -0.03, p = 0.03). An example of association with positive MOC value was depression score (MOC 0.06, p = 0.003). Further associations included maximal exercise capacity, blood pressure, heart rate and the rehabilitation centre attended.

CONCLUSION: Our results emphasize the necessity to take into consideration baseline characteristics when evaluating the success of CR and setting treatment targets for older patients.