Continuous Positive Airway Pressure Improves Sleep Apnea Associated Fatty Liver

Abstract

Treatment of sleep apnea can improve liver enzyme abnormalities in patients with nonalcoholic fatty liver disease. However, the effect of continuous positive airway pressure therapy for sleep apnea on liver fat accumulation was not assessed. Liver biopsy is the "gold standard" for determining and quantifying liver fat accumulation; however, obtaining two separate liver biopsies is challenging. We examined, using a newly described computerized tomography method to quantify liver fat accumulation, whether treatment of sleep apnea improves liver steatosis. In a prospective cohort study, patients diagnosed with obstructive sleep apnea, at Assaf Harofeh Medical Center's sleep laboratory, were identified. Patients completed a questionnaire and underwent blood tests for liver enzymes and lipid profile, and computed tomography scans to determine the liver attenuation index. Patients with liver attenuation index <or=-10 (correlating with histological macrovesicular steatosis >or=30%) were treated with continuous positive airway pressure for 2-3 years. Subsequently, patients underwent repeat blood tests and tomography scans. Of 47 patients who were analyzed, 16 had a low liver attenuation index (<or=-10). Patients with moderate-severe sleep apnea had worse liver attenuation index compared with patients with mild sleep apnea despite comparable body mass index and triglycerides levels. Patients who were compliant with 2-3 years of continuous positive airway pressure treatment demonstrated significant improvement in the mean liver attenuation index, whereas noncompliant patients did not. Patients with nonalcoholic fatty-liver disease may benefit from identification and treatment for obstructive sleep apnea because treatment may improve liver steatosis.

Effects of 8 weeks of continuous positive airway pressure on abdominal adiposity in obstructive sleep apnoea

“…However, we have recently shown that treatment of OSA with CPAP reduces postprandial lipids after only 8 weeks [17]. In the present study, although we could not also demonstrate significant reductions in abdominal or liver fat over a similar treatment period, an uncontrolled study using CPAP that assessed liver fat over 2-3 yrs did demonstrate a reduction in liver fat [16]. Hence, it is possible that a longer treatment period may eventually also show a benefit [17,28].…”

“…Markers of hypoxia have been demonstrated to be associated with elevated serum aminotransferase levels [14]. Similarly to visceral fat, however, there are contrasting results on the effect of nasal CPAP on the biochemical markers of NALFD in patients with OSA [12,15,16].…”

Altered gut–liver axis and hepatic adiponectin expression in OSAS: novel mediators of liver injury in paediatric non-alcoholic fatty liver

“…Unravelling mechanisms mediating OSAS-associated liver injury in NAFLD would have major research and clinical implications, as current therapeutic approaches to paediatric OSAS yield disappointing results: severe OSAS persists in as many as 50% of children after adeno-tonsillectomy, especially in the presence of obesity and severe OSAS;23 CPAP therapy improves polysomnographic parameters and surrogate markers of NAFLD,28 29 but its feasibility and patient adherence in children remain an issue 10. Therefore, it is important to investigate the novel alternative or complementary strategies for the treatment of paediatric OSAS.…”

Liver enzymes in obstructive sleep apnoea syndrome

“…Several cross-sectional studies have reported elevated levels of liver enzymes in patients with OSAS. Shpirer et al [41] demonstrated increased ALT, AST, and alakaline phosphate in adult patients with moderate to severe OSA. In a study by Gude et al [42] serum gamma glutamine transferease levels directly correlated with a degree of nocturnal hypoxemia in OSA patients.…”