Peak Work Rate during Exercise Could Detect Frailty Status in Elderly Patients with Stable Heart Failure

The Kihon Checklist (KCL) is a reliable tool for determining frailty status in the elderly. However, there is no information in the literature about the relationship between frailty status and exercise capacity. Here, we examined the associations between cardiopulmonary exercise testing parameters and frailty status in elderly patients with stable heart failure (HF).Ninety-two elderly patients with stable HF were evaluated using cardiopulmonary exercise testing and the KCL. A KCL score of 0-3 was classified as robust, 4-7 as pre-frail, and ≥ 8 as frail.Mean age, peak VO₂, and KCL score were 81.7 years, 13.2 mL/kg/minute, and 10.7, respectively. KCL score was significantly correlated with peak VO₂ (r = -0.527, P < 0.001) and peak work rate (r = -0.632, P < 0.001). In patients with frailty (n = 63), the peak work rate (WR) was significantly lower than it was in patients without frailty (n = 29; 39.9 versus 69.5 W, respectively; P < 0.001). Multivariate analysis revealed that peak WR and peak systolic blood pressure were significant, independent predictors of frailty (β = -0.108 and -0.045, respectively). In a diagnostic performance plot analysis, a cutoff value for peak WR of 51.9 W was the best predictor of frailty.Frailty status was significantly associated with peak WR and peak systolic blood pressure in elderly patients with stable HF. Therefore, cardiopulmonary exercise testing may be useful for assessing frailty status in this patient population.