Patients with acute decompensated heart failure who were frail at baseline improved more with targeted, early physical rehabilitation than those who were prefrail, a new analysis of the REHAB-HF study suggests.
“The robust response to the intervention by frail patients exceeded our expectations,” Gordon R. Reeves, MD, PT, of Novant Health Heart and Vascular Institute, Charlotte, N.C., told this news organization. “The effect size from improvement in physical function among frail patients was very large, with at least four times the minimal meaningful improvement, based on the Short Physical Performance Battery (SPPB).”
Furthermore, the interaction between baseline frailty status and treatment in REHAB-HF was such that a 2.6-fold larger improvement in SPPB was seen among frail versus prefrail patients.
However, Dr. Reeves noted, “We need to further evaluate safety and efficacy as it relates to adverse clinical events. Specifically, we observed a numerically higher number of deaths with the REHAB-HF intervention, which warrants further investigation before the intervention is implemented in clinical practice.”
The study was published online in JAMA Cardiology.
Interpret with caution
Dr. Reeves and colleagues conducted a prespecified secondary analysis of the previously published Therapy in Older Acute Heart Failure Patients (REHAB-HF) trial, a multicenter, randomized controlled trial that showed that a 3-month early, transitional, tailored, multidomain physical rehabilitation intervention improved physical function and quality of life (QoL), compared with usual care. The secondary analysis aimed to evaluate whether baseline frailty altered the benefits of the intervention or was associated with risk of adverse outcomes.
According to Dr. Reeves, REHAB-HF differs from more traditional cardiac rehab programs in several ways.
- The intervention targets patients with acute HF, including HF with preserved ejection fraction (HFpEF). Medicare policy limits standard cardiac rehabilitation in HF to long-term patients with HF with reduced ejection fraction (HFrEF) only who have been stabilized for 6 weeks or longer after a recent hospitalization.
- It addresses multiple physical function domains, including balance, mobility, functional strength, and endurance. Standard cardiac rehab is primarily focused on endurance training, which can result in injuries and falls if deficits in balance, mobility, and strength are not addressed first.
- It is delivered one to one rather than in a group setting and primarily by physical therapists who are experts in the rehabilitation of medically complex patients.
- It is transitional, beginning in the hospital, then moving to the outpatient setting, then to home and includes a home assessment.
For the analysis, the Fried phenotype model was used to assess baseline frailty across five domains: unintentional weight loss during the past year; self-reported exhaustion; grip strength; slowness, as assessed by gait speed; and low physical activity, as assessed by the Short Form-12 Physical Composite Score.
At the baseline visit, patients were categorized as frail if they met three or more of these criteria. They were categorized as prefrail if they met one or two criteria and as nonfrail if they met none of the criteria. Because of the small number of nonfrail participants, the analysis included only frail and prefrail participants.
The analysis included 337 participants (mean age, 72; 54%, women; 50%, Black). At baseline, 57% were frail, and 43% were prefrail.
A significant interaction was seen between baseline frailty and the intervention for the primary trial endpoint of overall SPPB score, with a 2.6-fold larger improvement in SPPB among frail (2.1) versus prefrail (0.8) patients.
Trends favored a larger intervention effect size, with significant improvement among frail versus prefrail participants for 6-minute walk distance, QoL, and the geriatric depression score.
“However, we must interpret these findings with caution,” the authors write. “The REHAB-HF trial was not adequately powered to determine the effect of the intervention on clinical events.” This plus the number of deaths “underscore the need for additional research, including prospective clinical trials, investigating the effect of physical function interventions on clinical events among frail patients with HF.”
To address this need, the researchers recently launched a larger clinical trial, called REHAB-HFpEF, which is powered to assess the impact of the intervention on clinical events, according to Dr. Reeves. “As the name implies,” he said, “this trial is focused on older patients recently hospitalized with HFpEF, who, [compared with HFrEF] also showed a more robust response to the intervention, with worse physical function and very high prevalence of frailty near the time of hospital discharge.”