Alteration of the gut microbiota in patients with nonalcoholic fatty liver disease and obstructive sleep apnea: a multiplied burden

Nonalcoholic fatty liver disease (NAFLD), a globally prevalent condition with an increasing trend, is frequently associated with obstructive sleep apnea (OSA). This study investigated the clinical characteristics and gut microbiota alterations in patients with NAFLD and OSA. Comprehensive evaluations included clinical examinations, body mass index (BMI), blood pressure, laboratory tests, fatty liver index (FLI), liver imaging, cardiovascular assessments, polysomnography, and stool analysis for dysbiosis, with next-generation 16S ribosomal RNA sequencing performed in patients with dysbiosis. Patients with OSA exhibited more advanced liver damage, higher BMI and FLI, and increased prevalence of comorbidities such as diabetes, dyslipidemia, metabolic syndrome, atherosclerotic plaques, ischemic heart disease, diastolic heart failure, and pulmonary hypertension. Significant correlations were observed between the severity of nonalcoholic steatohepatitis (NASH) and dysbiosis, as well as between dysbiosis and FLI. Gut microbiota analysis revealed reduced biodiversity, imbalances in Firmicutes/Bacteroidetes ratios, and altered levels of key microbial species such as Faecalibacterium prausnitzii, Akkermansia muciniphila, and Prevotella spp. Patients with NAFLD and OSA exhibited more severe liver damage, increased metabolic and cardiovascular risks, and notable gut microbiota alterations. These findings suggest that gut microbiota assessment may offer valuable insights for tailored therapeutic interventions to improve patient outcomes. Keywords: Nonalcoholic fatty liver disease; obstructive sleep apnea; gut microbiota alterations.