Uptake and Effectiveness of Outpatient vs. Residential Cardiac Rehabilitation After Myocardial Infarction: A Nationwide Analysis.

Abstract

Aims: To estimate the participation in, and the comparative effectiveness of, short-term residential and comprehensive outpatient cardiac rehabilitation (CR), after the latter was introduced in Slovenia by establishing dedicated regional CR centers.

Methods: We extracted and analyzed data on all patients hospitalized for myocardial infarction in Slovenia (n = 15,639), focusing on CR participation - either comprehensive outpatient (introduced in 2017) or short-term residential (available throughout the study period 2015-2021). Impact on nation-wide CR participation rates was assessed by interrupted time series analysis; impact on patient-level outcomes (all-cause mortality and cardiovascular hospitalizations) was assessed using Kaplan Meier estimators and 'doubly robust' Cox regression with propensity score-derived inverse probability of treatment weighting.

Results: Of the 11,815 eligible patients (event-free after 180-day landmark), 3819 (32.3%) attended CR. Nation-wide CR participation rates increased both in level (9.7%, 95% CI 6.3-3.1) and in trend (0.41% per month, 95% CI 0.22-0.60) after outpatient CR was introduced in 2017. After propensity score-based adjustment, participation in either CR was associated with lower event rates (12.8%, 17.2%, and 21.0% at 3-year follow-up for outpatient, residential, and no CR, respectively; p < 0.001). Risk reductions were significant for composite outcomes (outpatient: HR 0.58, 95% CI 0.47-0.70; residential: HR 0.79, 95% CI 0.68-0.93) and all-cause mortality (outpatient: HR 0.56, 95% CI 0.38-0.83; residential: HR 0.59, 95% CI 0.45-0.77), whereas the risk reduction for cardiovascular hospitalizations was only significant for outpatient CR (HR 0.60, 95% CI 0.48-0.74). The incremental cost-effectiveness ratio per life-year gained was €6421 and €7381 for outpatient and residential CR, respectively.

Conclusions: Participation in either CR improves outcomes after myocardial infarction, but comprehensive outpatient CR conveys superior risk reductions, primarily through reduced cardiovascular hospitalizations.

Lay summary: Our study highlights the importance of expanding cardiac rehabilitation services (by setting up dedicated regional comprehensive outpatient centers) and provides new evidence on improved outcomes in patients after myocardial infarction, who undergo cardiac rehabilitation. While previous studies have demonstrated the efficacy and effectiveness of cardiac rehabilitation, ours is the first to compare two distinctive cardiac rehabilitation modalities - comprehensive outpatient (introduced in 2017) and short-term residential (available throughout the study period 2015-2021).In our nationally representative population of patients after myocardial infarction (n = 15,639), participation in cardiac rehabilitation increased both in level (by ~10%) and in trend (by ~0.4% per month) after dedicated cardiac rehabilitation centers were established. Participation in either comprehensive outpatient or short-term residential cardiac rehabilitation was associated with a significant 42% and 21% risk reduction in the primary outcome (death or cardiovascular hospitalization) respectively, after propensity score-based adjustment. Mortality was also reduced (by 46% and 41%, respectively), whereas the risk reduction for hospitalization was only significant in patients undergoing comprehensive cardiac rehabilitation (by 60%).Participation in either cardiac rehabilitation program improves cardiovascular outcomes, but comprehensive outpatient cardiac rehabilitation yields superior risk reductions, primarily through reduced cardiovascular hospitalizations.

Key learning points: What is already known?: Cardiac rehabilitation improves outcomes in patients with coronary artery disease.Despite its established efficacy, cardiac rehabilitation participation remains suboptimal. Improving access to cardiac rehabilitation through establishing dedicated regional centers may improve participation, but also crowd-out existing options of cardiac rehabilitation.The comparative effectiveness of different cardiac rehabilitation modalities (e.g., comprehensive outpatient versus short-term residential cardiac rehabilitation) remains understudied.What does this study add?: Expanding cardiac rehabilitation services (by setting up dedicated regional comprehensive outpatient centers) significantly improves participation in cardiac rehabilitation after myocardial infarction.Participation in either comprehensive outpatient or short-term residential cardiac rehabilitation after myocardial infarction is associated with improved outcomes (i.e., a significant 42% and 21% risk reduction in death or cardiovascular hospitalization, respectively).Comprehensive outpatient cardiac rehabilitation yields superior risk reductions primarily through reduced cardiovascular hospitalizations.