Liver function following continuous positive airway pressure therapy in obstructive sleep apnea patients

Obstructive sleep apnea (OSA) and the resulting decrease in oxygen saturation (SaO2) are associated with non-alcoholic fatty liver disease. Continuous positive airway pressure (CPAP) is recognized as the gold standard treatment for OSA. The effects of OSA treatment on liver function have been investigated previously with conflicting results. We evaluated the association between liver enzyme levels and severity of OSA, and whether CPAP treatment normalizes liver enzyme levels. Thirty patients with severe, newly diagnosed OSA (apnea hypopnea index, AHI > 30) were recruited. Patients were divided into 15 CPAP (AHI: 37.5±7.3 events/h, lowest SaO2: 85.6±5.0%) and 15 non-CPAP (AHI: 37.5±5.2 events/h, lowest SaO2: 83.9±3.4%) treatment groups. Each group had six males and nine females, age matched. The levels of liver enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured in both groups before and after three months of CPAP therapy. AHI was positively correlated with ALT (r = 0.5901, p