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/height 2 ) <7.0 kg/m 2 . Oxygen uptake efficiency slope (OUES), ventilation (VE), oxygen uptake (VO 2 ), and carbon dioxide output (VCO 2 ) were measured by a cardiopulmonary exercise test.

Results: Sarcopenia was identified in 29 patients (17%). At the first ventilatory threshold, VE/VO 2 (36.9 ± 5.9 vs 32.7 ± 6.5; P = .003) and VE/VCO 2 (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 VO 2 (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/VCO 2 (42.9 ± 8.9 vs 38.7 ± 8.4; P = .025) was increased. OUES was positively correlated with ALM/height 2 ( 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/height 2 (OR = 2.166; 95% CI, 1.338-3.504; P = .002), and VO 2peak (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.