Background and Aims: Compared with usual care, clinical trials of cardiac rehabilitation (CR) have demonstrated a significant reduction in all-cause and cardiac mortality as well as greater improvements in cardiac risk factors. One of the criticisms of this literature is the selection of participants in clinical trials, with preponderance of mostly male, younger, and fitter subjects. The extent to which survival benefits associated with CR services applies to real-world settings and across the breadth of age and gender of typical CR participants remain unclear.

Objective: To compare the long-term survival and downstream health service utilization between CR participants and nonparticipants following index cardiovascular hospitalizations.

Method: Retrospective matched cohort study conducted in Ontario, Canada. Two thousand forty-two cardiac rehabilitation participants (from the Toronto Rehab Institute) and 2,042 controls (drawn from the general Ontario health databases), all of whom had been recently hospitalized for, and survived 1 year following acute cardiac events between 1999 and 2003, were included. Population controls were identified using a 1:1 match on several key prognostic variables including index cardiac event, age, gender, socioeconomic status, geography, and preceding cardiac and noncardiac hospitalizations. A Cox Proportional Hazards model was developed to examine the association between CR and survival after adjustment for residual differences in the baseline characteristics, variations in downstream use of coronary procedures, use and adherence of evidence-based therapies (ie, statins, ACE inhibitors, and [beta]-blockers).

Results: Participation in CR was associated with a 50% higher survival rate (2.6% vs 5.1%, P < .001) as compared with population-matched controls, with the greatest benefit seen in those who fully completed the yearlong program (hazard ratio 0.24, 95% CI 0.12-0.46, P < .001 compared with control). A survival benefit for CR completers was seen in both those older than 66 (hazard ratio 0.09, 95% CI 0.02-0.50, P = .005 compared with control) and those younger than 66 (hazard ratio 0.31, 95% CI 0.11-0.87, P = .03 compared with control). The difference in mortality across genders was also consistent for CR completers (in men: hazard ratio 0.22, 95% CI 0.09-0.51, P = .001, compared with control) but not quite significant in the female cohort (hazard ratio 0.05, 95% CI 0.002-1.13, P = .06, compared with control) owing to the smaller total sample of women (n = 514). The difference in mortality between CR participants and nonparticipants was not explained by variation in use of evidence-based pharmacotherapy, adherence, or other health services.

Limitation: Treatment allocation was nonrandomized.

Conclusions: Participation in and completion of a cardiac rehabilitation program in the real world is associated with a significant reduction in all-cause mortality following acute cardiac events. This important effect is consistent across age and gender.