Clinical Effectiveness and Utilisation of Cardiac Rehabilitation After Hospital Discharge: Data Linkage Analysis of 84,064 Eligible Discharged Patients (2016-2021)-2021)

Background Despite the highest levels of evidence on cardiac rehabilitation (CR) effectiveness, its translation into practice is compromised by low participation. Aim This study aimed to investigate CR utilisation and effectiveness in South Australia. Methods This retrospective cohort study used data linkage of clinical and administrative databases from 2016 to 2021 to assess the association between CR utilisation (no CR received, commenced without completing, or completed) and the composite primary outcome (mortality/cardiovascular re-admissions within 12 months after discharge). Cox survival models were adjusted for sociodemographic and clinical data and applied to a population balanced by inverse probability weighting. Associations with non-completion were assessed by logistic regression. Results Among 84,064 eligible participants, 74,189 did not receive CR, with 26,833 of the 84,064 (31.9%) participants referred. Of these, 9,875 (36.8%) commenced CR, and 7,681 of the 9,875 (77.8%) completed CR. Median waiting time from discharge to commencement was 40 days (interquartile range, 23-79 days). Female sex (odds ratio [OR] 1.12; 95% CI 1.01-1.24; p=0.024), depression (OR 1.17; 95% CI 1.05-1.30; p=0.002), and waiting time >28 days (OR 1.15; 95% CI 1.05-1.26; p=0.005) were associated with higher odds of non-completion, whereas enrolment in a telehealth program (OR 0.35; 95% CI 0.31-0.40; p<0.001) was associated with lower odds of non-completion. Completing CR (hazard ratio [HR] 0.62; 95% CI 0.58-0.66; p<0.001) was associated with a lower risk of 12-month mortality/cardiovascular re-admissions. Commencing without completing was also associated with decreased risk (HR 0.81; 95% CI 0.73-0.90; p<0.001), but the effect was lower than for those completing CR (p<0.001). Conclusions Cardiac rehabilitation (CR) attendance is associated with lower all-cause mortality/cardiovascular re-admissions, with CR completion leading to additional benefits. Quality improvement initiatives should include promoting referral, women's participation, access to telehealth, and reduction of waiting times to increase completion.