Cardiac Rehabilitation After Heart Failure Hospitalization Tied to 45% Lower One-Year Death Risk in Medicare Patients

Heart failure remains one of the most formidable challenges in modern medicine, and a new study of more than 116,000 older Americans has added fresh urgency to a question that cardiologists have debated for years: does cardiac rehabilitation actually save lives after a hospitalization for heart failure? According to research published in the Journal of General Internal Medicine, Medicare beneficiaries who started cardiac rehabilitation within 180 days of leaving the hospital had a dramatically lower risk of dying within one year compared with those who never enrolled. The finding is striking not only for its magnitude but also for the sobering reality it exposes: only about 1.5 percent of eligible patients ever begin the therapy.

The study, led by Dr. Tara Lagu of MaineHealth Institute for Research and colleagues at the University of Massachusetts Chan Medical School – Baystate, Duke Health, and New York University, drew on Medicare claims data from 2017. The researchers identified 116,302 beneficiaries who had been hospitalized with a principal diagnosis of heart failure, a condition that affects millions of older adults and carries an approximate 50 percent mortality rate within five years. The cohort had a mean age of 82 years, and 54 percent were women, reflecting the demographics of the population most vulnerable to this chronic, progressive disease.

What the team found was a stark divide in survival. Overall, 35 percent of patients died within one year of hospital discharge. But among the small subset of 1,747 patients who initiated cardiac rehabilitation within 180 days of discharge, the one-year mortality rate was just 10.7 percent, compared with 35.2 percent among those who did not attend. That gap, however dramatic on its face, required sophisticated statistical machinery to interpret responsibly, because patients who make it to rehabilitation are not a random sample of the heart failure population.

To address this, the investigators employed stabilized inverse probability of treatment weighting, a technique that mathematically reweights the comparison groups so that patients who attended rehabilitation and those who did not become comparable across measured characteristics such as age, sex, frailty, heart failure subtype, and distance to the nearest rehabilitation facility. The method accounts for the fact that patients who did not attend cardiac rehabilitation were more likely to be older, female, frail, to have diastolic heart failure, and to live farther from a facility offering the service. After adjustment, participation in cardiac rehabilitation was associated with a 45 percent lower risk of death within one year of discharge, corresponding to a hazard ratio of 0.55 with a 95 percent confidence interval of 0.46 to 0.66.

The researchers were acutely aware of a methodological trap known as immortal time bias, a well-documented pitfall in pharmacoepidemiology and outcomes research. Because patients must survive long enough to begin rehabilitation, simply comparing attendees with non-attendees can artificially inflate the apparent benefit of treatment. To counter this, the team attributed the time before rehabilitation initiation as untreated time, ensuring that the survival advantage could not be an artifact of patients simply living long enough to enroll. This careful handling of time at risk is what separates rigorous observational analyses from naive comparisons, and it is one of the reasons the findings carry weight.

Beyond the primary analysis, the investigators ran a battery of sensitivity analyses designed to stress-test the result. These included landmark methods restricted to patients who survived the full 180 days, propensity score weighting, propensity score matching, and a dose-response analysis examining whether more sessions correlated with better outcomes. The estimates remained consistent across approaches, including within the subgroup of patients with a diagnosis of systolic heart failure, the form of the disease for which exercise-based rehabilitation has the strongest randomized trial evidence. The consistency of the signal across multiple analytic frameworks strengthens the argument that the association is not a statistical fluke.

The results build on a foundation of prior evidence. The landmark HF-ACTION randomized controlled trial, published in JAMA in 2009, demonstrated the efficacy and safety of exercise training in patients with chronic heart failure, and a 2019 Cochrane systematic review and meta-analysis confirmed that exercise-based rehabilitation reduces the risk of heart failure-related hospitalization. Medicare extended coverage for cardiac rehabilitation to patients with chronic heart failure in 2014, recognizing the therapy’s value. Yet participation rates have remained stubbornly low. Previous work by some of the same investigators documented enormous hospital-level variation in cardiac rehabilitation use among Medicare beneficiaries, and studies of referral patterns for heart failure with reduced ejection fraction have shown that even among patients who are eligible, enrollment is the exception rather than the rule.

Why do so few patients take advantage of a therapy that appears to be associated with such a substantial survival benefit? The answer lies in a tangle of logistical, financial, and human barriers. Research has shown that drive time to a rehabilitation facility affects utilization, that copayments are associated with lower attendance, and that ethnic minority groups face additional obstacles to participation. A qualitative study by members of the same research team, published under the evocative title It Was a Blur, explored the barriers that patients with heart failure encounter, capturing the disorientation many feel as they transition from hospital bed to outpatient care. For a population with a mean age of 82, transportation, frailty, and competing health priorities are not trivial hurdles.

The authors argue that their findings should inform how clinicians counsel patients with heart failure about cardiac rehabilitation, and that the evidence should be weighed in the development of clinical guidelines, research funding strategies, and payment policies. This is a consequential recommendation. If the association reflects even a fraction of a true causal effect, then expanding access to cardiac rehabilitation for heart failure survivors could translate into thousands of avoided deaths each year among Medicare beneficiaries alone. Proposals such as home-based cardiac rehabilitation, endorsed in a scientific statement from the American Association of Cardiovascular and Pulmonary Rehabilitation, the American Heart Association, and the American College of Cardiology, and hybrid models that blend supervised and remote sessions, represent practical avenues for reaching patients who cannot easily travel to a facility.

As with any observational study, caution is warranted before declaring causation. Even the most sophisticated weighting and matching cannot fully rule out the influence of unmeasured differences between patients who enroll in rehabilitation and those who do not, such as motivation, social support, or the intensity of outpatient follow-up. The researchers themselves acknowledge this limitation, and the study was approved by the Baystate Health Institutional Review Board with a waiver of informed consent, funded by the National Heart, Lung, and Blood Institute under award 1R01HL146884, with additional support to Dr. Quinn Pack under award K23 HL135440. Still, the convergence of this large Medicare analysis with randomized trial evidence, mechanistic plausibility, and prior observational data makes a compelling case that cardiac rehabilitation is an underused lifeline for one of medicine’s most vulnerable populations. For the 98.5 percent of heart failure patients who currently miss out, the message from this research is difficult to ignore: a therapy that demands only referral and persistence may be one of the most powerful tools available for extending life after a heart failure hospitalization.

Subject of Research: Association between cardiac rehabilitation initiation after heart failure hospitalization and one-year survival among Medicare beneficiaries

Article Title: Association Between Initiation of Cardiac Rehabilitation after Hospitalization for Heart Failure and 1-Year Survival Among Medicare Beneficiaries

Article References: Lagu, T., Priya, A., Lee, K., Pack, Q. R., Pekow, P. S., D’Aunno, T., & Lindenauer, P. K. (2026). Association Between Initiation of Cardiac Rehabilitation after Hospitalization for Heart Failure and 1-Year Survival Among Medicare Beneficiaries. Journal of General Internal Medicine. https://doi.org/10.1007/s11606-026-10739-2

Image Credits: AI Generated

DOI: 10.1007/s11606-026-10739-2

Keywords: cardiac rehabilitation, heart failure, Medicare, mortality, hospitalization, exercise training, observational study, propensity score, immortal time bias, older adults, survival, health policy