Abstract 19130: Referral to Cardiac Rehabilitation: A Quality Indicator Associated with Reduced Mortality

Abstract

Background: Cardiac Rehabilitation (CR) is an efficacious, evidence based treatment for reducing mortality and hospitalization in subjects with coronary artery disease (CAD). CR referral is an indicator of quality care in CAD patients. However, not all eligible subjects are referred for CR. The objective of this study was to assess predictors of referral to CR and the association between referral and mortality.

Methods: All subjects who underwent coronary angiography between 1995 and 2009 and were found to have CAD were included in this study (n=25,958, 24.6% female). Referral to CR and subsequent attendance were evaluated. Baseline characteristics were compared between those who were referred and not. Logistic regression models predicting referral were developed. Using cox proportional hazards models, survival was then compared across those who were not referred (NR), referred and did not attend, and referred and did attend.

Results: Of those subjects with CAD, 10236 (39.4%) were referred to CR; 58.4% of those referred attended CR. Rates of referral increased from 20.7 to 65.3% over the course of the study (p<0.0001). In multivariate models, older age, being female, and diabetes all predicted non-referral (all p<0.0001). Relative to the NR, those who were referred and did not attend had a hazard ratio (HR) for mortality of 0.55 (95% CI 0.51, 0.60); those who were referred and attended had a HR of 0.26 (95% CI 0.24, 0.29). When adjusted for age, sex, CAD severity, treatment (surgical, interventional, medical) and all clinical covariates, subjects who were referred and did not attend had a HR of 0.76 (95% CI 0.70, 0.82) and subjects who were referred and attended had a HR of 0.42 (95% CI 0.38, 0.46) for death relative to those who were NR.

Conclusion: While CR referral rates have improved over time, they remain suboptimal. High-risk subjects are the most likely to remain un-referred. Given the association between CR referral and reduced mortality, referral to CR is a justifiable quality indicator for CAD patient care. Efforts to improve referral should be undertaken.