Community or patient preferences for cost-effectiveness of cardiac rehabilitation: does it matter?
BACKGROUND
Few healthcare economic evaluations, and none in cardiac rehabilitation, report results based on both community and patient preferences for health outcomes. We published the results of a randomized trial of cardiac rehabilitation after myocardial infarction in 1994 in which preferences were measured using both perspectives but only patient preferences were reported. This secondary analysis uses both types of preference measurements.


METHODS
We collected community Quality of Well-Being (QWB) and patient Time Trade-off (TTO) preference scores from 188 patients (rehabilitation, n=93; usual care, n=95) on entry into the trial, at 2 months (end of the intervention) and again at 4, 8, and 12 months. Mean preference scores over the 12-month follow-up study period, estimates of quality-adjusted life years (QALYs) gained per patient, incremental cost-effectiveness ratios [costs inflated to 2006 US dollars] and probabilities of the cost-effectiveness of rehabilitation for costs per QALY up to USD100,000 are reported.


RESULTS
Mean QWB preference scores were lower (P<0.01) than the corresponding mean TTO preference scores at each assessment point. The 12-month changes in mean QWB and TTO preference scores were large and positive (P<0.001) with rehabilitation patients gaining a mean of 0.011 (95% confidence interval, -0.030 to +0.052) more QWB-derived QALYs, and 0.040 (-0.026, 0.107) more TTO-derived QALYs, per patient than usual care patients. The incremental cost-effectiveness ratio for QWB-derived QALYs was estimated at $60 270/QALY (about euro50 600/QALY) and at $16 580/QALY (about euro13 900/QALY) with TTO-derived QALYs. With a willingness to spend $100 000/QALY, the probability of rehabilitation being cost-effective is 0.58 for QWB-derived QALYs and 0.83 for TTO-derived QALYs.


CONCLUSION
This secondary analysis of data from a randomized trial indicates that cardiac rehabilitation is cost-effective from a community perspective and highly cost-effective from the perspective of patients.