Exercise Capacity and Pulmonary Capacitance Are Attenuated in Patients with Nonalcoholic Steatohepatitis = Exercise Capacity and Pulmonary Capacitance Are Attenuated in Patients with Nonalcoholic Steatohepatitis

다국어 초록 (Multilingual Abstract)

Purpose: The study was to investigate exercise capacity (peak oxygen uptake [peak VO₂]) and pulmonary capacitance (GX_cap), which is an estimate of pulmonary vascular capacitance, in patients with nonalcoholic steatohepatitis (NASH).
Methods: This study utilized a database of patients with NASH (n=26 [17 male and 9 female], aged 58.9±4.3 years) and healthy individuals (n=23 [12 male and 11 female, aged 58.6±7.9 years) who underwent a maximal exercise test on a recumbent cycle ergometer (Corival; Lode) in our laboratory. During cardiopulmonary exercise tests, breathing patterns and respiratory gas exchange including breathing efficiency (VE/VCO₂) and end-tidal CO₂ (PETCO₂) were measured. In addition, peak VO₂ was obtained via averaging the last 30 seconds at peak level and GX_cap was obtained by calculation as follows: GX_cap=oxygen pulse (O₂ pulse)×PETCO₂.
Results: The NASH group demonstrated reduced peak VO₂ relative to the healthy group (17.5±8.4 mL/kg/min vs. 34±10.2 mL/kg/min, respectively; p＜ 0.05). In addition, there was a higher VE/VCO₂ relationship in the NASH group relative to the healthy group (34.9±5.5 vs. 32.2±4.0, respectively; p＜ 0.05) and lower PETCO₂ in the NASH group compared to the healthy group (32.8±4.0 mm Hg vs. 35.3±3.8 mm Hg, respectively; p＜ 0.05). Furthermore, the NASH group showed lower GX_cap than the healthy group (456±150 vs. 551±202, respectively; p＜ 0.05).
Conclusion: Patients with NASH had reduced exercise capacity and pulmonary vascular capacitance relative to age-matched healthy adults and this may contribute to pulmonary pathophysiology in NASH.