Obstructive sleep apnea (OSA) is associated with the development and evolution of NAFLD, independent of obesity or other shared risk factors. The OSA–NAFLD association is related to the degree of nocturnal hypoxaemia in OSA. Animal models have largely focused on intermittent hypoxia, a key manifestation of OSA, to shed light on the mechanisms by which OSA may give rise to the complex metabolic disturbances that are seen in NAFLD.
Mechanisms involving obstructive sleep apnea and NAFLD are under increasing assessment. In this prospective study by GK Krolow et al. (Porto Alegre, Brazil), patients with at least one of metabolic syndrome criteria were initially assessed by the NAFLD fibrosis score and according to the outcome underwent liver biopsy. All patients performed polysomnography.
A multivariate analysis adjusted for obesity level, found that patients with moderate to severe OSA had an increased risk of hepatic fibrosis (odds ratio 1.22).