Purpose: Cardiac rehabilitation (CR) improves outcomes, yet early dropout is common. The purpose of the study was to determine whether a motivational telephone intervention among patients at risk for nonadherence would reduce early dropouts. Methods: We performed a randomized double-blind pilot study with the intervention group receiving the telephone intervention 1 to 3 d after outpatient CR orientation. The control group received the standard of care, which did not routinely monitor attendance until 2 wk after orientation. The primary outcome was the percentage of patients who attended their second exercise session as scheduled. Secondary outcomes included attendance at the second CR session at any point and total number of sessions attended. Because not everyone randomized to the intervention was able to be contacted, we also conducted a per-protocol analysis. Results: One hundred patients were randomized to 2 groups (age 62 ± 15 yr, 46% male, 40% with myocardial infarction) with 49 in the intervention group. Patients who received the intervention were more likely to attend their second session as scheduled compared with the standard of care (80% vs 49%; relative risk = 1.62; 95% CI, 1.18-2.22). Although there was no difference in total number of sessions between groups, there was a statistically significant improvement in overall return rate among the per-protocol group (87% vs 66%; relative risk = 1.31; 95% CI, 1.05-1.63). Conclusions: A nursing-based telephone intervention targeted to patients at risk for early dropout shortly after their CR orientation improved both on-time and eventual return rates. This straightforward strategy represents an attractive adjunct to improve adherence to outpatient CR.

Background: Nonadherence to cardiac rehabilitation (CR) is common despite the benefits of completing a full program. Adherence might be improved if patients at risk of early dropout were identified and received an intervention. Methods: Using records from patients who completed ≥1 CR session in 2016 (derivation cohort), we employed multivariable logistic regression to identify independent patient-level characteristics associated with attending <12 sessions of CR in a predictive model. We then evaluated model discrimination and validity among patients who enrolled in 2017 (validation cohort). Results: Of the 657 patients in our derivation cohort, 318 (48%) completed <12 sessions. Independent risk factors for not attending ≥12 sessions were age <55 yr (OR = 0.23, P < .001), age 55 to 64 yr (OR = 0.35, P < .001), age ≥75 yr (OR = 0.64, P = .06), smoker within 30 d of CR enrollment (OR = 0.40, P = .001), low risk for exercise adverse events (OR = 0.54, P = .03), and nonsurgical referral diagnosis (OR = 0.66, P = .02). Our model predicted nonadherence risk from 23-90%, had acceptable discrimination and calibration (C-statistics = 0.70, Harrell's E 50 and E 90 2.0 and 3.6, respectively) but had fair validity among 542 patients in the validation cohort (C-statistic = 0.62, Harrell's E 50 and E 90 2.1 and 11.3, respectively). Conclusion:We developed and evaluated a single-center simple risk model to predict nonadherence to CR. Although the model has limitations, this tool may help clinicians identify patients at risk of early dropout and guide intervention efforts to improve adherence so that the full benefits of CR can be realized for all patients.