Cardiac Rehabilitation Participation Patterns in a Large, Tertiary Care Center: Evidence for Selection Bias

BACKGROUND: Clinical practice guidelines have been published for cardiac rehabilitation, directing programs to address secondary risk-reduction issues. The role of risk factor profiles in the referral of patients to cardiac rehabilitation programs has not been evaluated. METHODS: Patients from the Cardiovascular Information Registry at the Cleveland Clinic Foundation (CCF) who entered the CCF hospital-based cardiac rehabilitation program (n = 371) were compared with those who did not participate in the CCF program (n = 2960) with respect to gender, demographics, and risk factor profile for CAD. A random subset of those who did not participate in the CCF program (n = 100) was interviewed by phone to determine participation patterns in other rehabilitation programs. RESULTS: Only 11% of patients participated in CCF-based program. Standard risk factors were similar between participants and nonparticipants. Rehabilitation patients were younger (63 +/- 10 versus 66 +/- 10, P < 0.01) and as a group had better left ventricular function (moderate-severe left ventricle: 16% versus 23%, P < 0.01) than nonparticipants. Women were underrepresented in the CCF rehabilitation population (20% versus 30%, P < 0.01). Of the phone survey sample, 21% of patients entered other community-based rehabilitation programs. Similar trends with respect to risk factors, younger age, and better left ventricular function were noted for the community subset. However, women accounted for a greater percentage of the participants in the community programs than the CCF-based program (42.8% versus 19.7%, P < 0.03). CONCLUSIONS: Conclusions based on institution-specific programs likely underestimate overall participation in cardiac rehabilitation. Traditional risk factors apparently are not considered when referring patients to cardiac rehabilitation programs. Younger patients with lower mortality risks preferentially participate in rehabilitation programs. Women are more likely to participate in community-based programs. Overall use of cardiac rehabilitation programs remains low.