There is an inverse relationship between phase 2 cardiac rehabilitation (CR) visits and all-cause mortality. Phase 3 CR is a maintenance exercise program for which clinical outcomes are uncertain. This retrospective study describes the association between phase 3 CR participation and clinical events among patients with ischemic heart disease after completion of phase 2 CR.
Patients who completed 12 visits of phase 2 CR as provided by their health insurance were categorized on the basis of their frequency of participation (ie, none, irregular, and regular) in phase 3 CR during the 8 weeks after phase 2 CR. Cox regression analysis was used to evaluate the association between phase 3 CR participation and risk for a composite outcome that included all-cause mortality, nonfatal myocardial infarction, or heart failure hospitalization.
Among 2039 patients (32% women; age = 59 ± 10 years) who completed phase 2 CR, 101 were regular and 129 were irregular participants of phase 3 CR. Over a median followup of 5.6 years, 556 (27%) patients experienced the outcome. Neither irregular nor regular participation in phase 3 CR was significantly associated with risk for the outcome in unadjusted (P = .671 and P = .396, respectively) or adjusted (P = .737 and P = .890, respectively) analyses.
We did not observe an incremental clinical benefit from weekly participation in Phase 3 CR after completion of phase 2 CR among patients with ischemic heart disease. Additional research addressing the dose-response relationship between phase 2 and 3 CR and clinical outcomes is needed.