The American Heart Association and American College of Cardiology recommend cardiac rehabilitation after patients suffer an acute MI. Research has indicated cardiac rehabilitation can improve survival. Still, only a small percentage of patients participate in the programs.

A recent retrospective cohort study confirmed the significant survival benefit of cardiac rehabilitation during the year following an acute MI, although other health status outcomes were similar among patients who did and did not participate in the programs. The trial also found that 40.9 percent of patients enrolled in cardiac rehabilitation within six months of hospitalization for acute MI.

Lead researcher Faraz Kureshi, MD, MSc, of Saint Luke’s Mid America Heart Institute in Kansas City, Missouri, and colleagues published their results online in JAMA Cardiology on Oct. 19.

The researchers examined 4,929 patients who enrolled in two acute MI registries from Jan. 1, 2003 to June 28, 2004 and from April 11, 2005 to Dec. 31, 2008. They included patients who had data available on baseline health status, follow-up health status at 6 or 12 months and participation in cardiac rehabilitation.

They obtained data on participation in cardiac rehabilitation from telephone interviews at one and six months after hospital discharge. They also assessed health status at baseline and at follow-up interviews using the Seattle Angina Questionnaire (SAQ) and the 12-Item Short-Form Health Survey (SF-12).

A higher percentage of patients who participated in cardiac rehabilitation were male, white, married, employed full-time, had health insurance coverage for medications and received coronary revascularization for acute MI during their hospitalization.

The SAQ and SF-12 scores were similar between the groups at baseline and not clinically significant except for the SAQ physical limitation score, which favored the cardiac rehabilitation group. During the year after acute MI, the mean health status scores improved in all domains for both groups except for the SAQ treatment satisfaction score.

A propensity score-matched analysis found that health status outcomes and mean SAQ scores were clinically similar for patients who did and did not participate in cardiac rehabilitation. During seven years of follow-up in the propensity-matched patients, participants in cardiac rehabilitation had a 41 percent lower hazard rate of mortality.

The study had a few limitations, according to the researchers, including that patients self-reported their participation in cardiac rehabilitation. They also did not have data on the type, intensity, frequency and length of the patients participation in cardiac rehabilitation. In addition, the groups had significant differences in several characteristics at baseline, which could have led to unmeasured confounding.

“Our results underscore the need for further investigation of the effect of participation in [cardiac rehabilitation] on health status to identify if and how [cardiac rehabilitation] programs can better maximize health status outcomes for patients after [acute MI],” the researchers wrote.