Association of Sarcopenia and Oxygen Uptake Efficiency Slope in Male Patients with Heart Failure

Purpose: Sarcopenia, the loss of muscle mass and function, is a common comorbidity in patients with heart failure (HF). The skeletal muscle modulates the respiratory response during exercise. However, whether ventilatory behavior is affected by sarcopenia is still unknown. Methods: We enrolled 169 male patients with HF. Muscle strength was measured by a handgrip dynamometer. Body composition was measured with dual-energy X-ray absorptiometry. Sarcopenia was defined by handgrip strength <27 kg and appendicular lean mass divided by height squared (ALM/height2) <7.0 kg/m2. Oxygen uptake efficiency slope (OUES), ventilation (VE), oxygen uptake (VO2), and carbon dioxide output (VCO2) were measured by a cardiopulmonary exercise test. Results: Sarcopenia was identified in 29 patients (17%). At the first ventilatory threshold, VE/VO2 (36.9 ± 5.9 vs 32.7 ± 6.5; P =.003) and VE/VCO2 (39.8 ± 7.2 vs 35.3 ± 6.9; P =.004) were higher in patients with sarcopenia compared to those without sarcopenia. At the exercise peak, compared to patients without sarcopenia, patients with sarcopenia had lower OUES (1186 ± 295 vs 1634 ± 564; P <.001), relative VO2 (16.2 ± 5.0 vs 19.5 ± 6.5 mL/kg/min; P =.01), and VE (47.3 ± 10.1 vs 63.0 ± 18.2 L/min; P <.0001), while VE/VCO2 (42.9 ± 8.9 vs 38.7 ± 8.4; P =.025) was increased. OUES was positively correlated with ALM/height2 (r = 0.36; P <.0001) and handgrip strength (r = 0.31; P <.001). Hemoglobin (OR = 1.149; 95% CI, 0.842-1.570; P =.038), ALM/height2 (OR = 2.166; 95% CI, 1.338-3.504; P =.002), and VO2peak (OR = 1.377; 95% CI, 1.218-1.557; P <.001) were independently associated with OUES adjusted by cofounders. Conclusions: Our results suggest that sarcopenia is related to impaired ventilatory response during exercise in patients with HF.