Background: Whether upper-extremity and lower-extremity muscle strength can predict a prognosis of congestive heart failure (CHF) patients is unclear. This study evaluated the impact of muscle strength on long-term mortality in patients with CHF.
Design: Prospective observational study of male Japanese CHF patients.
Methods: Clinical characteristics (age, body mass index, left ventricular ejection fraction, heart failure etiology, and medications) were obtained from hospital records of 148 male outpatients with stable CHF. Brain natriuretic peptide was determined as an index of disease severity. Peak oxygen uptake ((Equation is included in full-text article.)), handgrip, and knee extensor muscle strength were also determined.
Results: After 1331.9+/-700.3 days of follow-up, 13 cardiovascular-related deaths occurred, and the patients were divided into two groups: survival (n=135) and nonsurvival (n=13). No significant differences were found between the groups in clinical characteristics, brain natriuretic peptide levels, and knee extensor muscle strength. Peak(Equation is included in full-text article.)(P=0.011) and handgrip strength (P=0.008) were significantly lower in the nonsurvival versus survival group. Left ventricular ejection fraction, peak(Equation is included in full-text article.), and handgrip strength were found by univariate Cox proportional hazards analysis to be significant prognostic indexes of survival. Multivariate analysis, however, revealed handgrip strength to be an independent predictor of prognosis. A handgrip strength cutoff value of 32.2 kgf was determined by the analysis of receiver-operating characteristics and was assessed. Kaplan-Meier survival curves after log-rank test showed significant prognostic difference between the two groups (P=0.008).
Conclusion: Handgrip strength may be useful for forecasting prognosis in patients with CHF.