Association between obstructive sleep apnoea and liver fibrosis in patients with suspected nonalcoholic fatty liver disease

Abstract

Study objectives: The association between obstructive sleep apnea (OSA) and liver fibrosis has been primarily evaluated using noninvasive tools or in selected populations (bariatric surgery). The aim of the study was to determine whether OSA is associated with liver fibrosis in patients with suspected nonalcoholic fatty liver disease (NAFLD) referred for liver biopsy.

Methods: Patients who underwent percutaneous liver biopsy for suspected NAFLD were prospectively included and investigated by in-lab polysomnography. Liver lesions were evaluated using the NASH-CRN scoring system and advanced fibrosis was defined as F ≥ 3. Moderate to severe OSA was defined by an apnoea-hypopnoea index (AHI) ≥15 events/h.

Results: Among the 97 patients included in the study, 40 exhibited advanced fibrosis, while 63 demonstrated moderate to severe OSA. The prevalence of moderate to severe OSA in patients with advanced fibrosis was 82% versus 52% in patients with F0-2 fibrosis stage (p<.0037). The association between moderate to severe OSA and advanced fibrosis remained significant after adjustment for sex, age, diabetes and obesity with an OR of 3.48 (confidence interval, 1.03-11.83; p=.045). Similar association was found with nocturnal hypoxia markers (oxygen desaturation index and the time spent under 90% of saturation). No association was observed between moderate to severe OSA and steatosis or nonalcoholic steatohepatitis.

Conclusions: Utilizing the gold-standard tools for OSA and NAFLD diagnosis in a multicentric cohort of biopsy-proven NAFLD patients, an independent association between OSA and liver fibrosis was confirmed.

Keywords: liver fibrosis; nonalcoholic fatty liver disease, NASH; obstructive sleep apnea.