Sleep quality and its relation to anthropometric and metabolic factors in overweight/obese patients with non-alcoholic fatty liver disease: a case-control study

In this case-control study, sleep duration and quality were assessed in 72 overweight or obese patients with newly diagnosed NAFLD as "cases" compared with 72 age-and sex-matched adults without NAFLD as "controls". Weight, height, and the circumferences of the waist, hip, and neck, as well as metabolic (glycemia, lipid profile, liver function biomarkers) and hematological factors (complete blood cell count), were assessed. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), and the global PSQI score was classified into good sleep quality (< 6) and low sleep quality (≥ 6). Cases showed significantly greater body mass index (BMI), waist circumference, and waist-to-height ratio as well as serum levels of glucose, hemoglobin A1c, triglyceride, total cholesterol, low-density lipoprotein cholesterol, alanine and aspartate aminotransferases, and 25(OH)D than controls (p < 0.05). The PSQI score was significantly correlated with serum levels of high-density lipoprotein cholesterol, total iron-binding capacity, and 25(OD in patients with NAFLD. Although age and BMI were more likely to be associated with NAFLD (p = 0.042 and p < 0.001, respectively), no association was found for PSQI score as well as its components in NAFLD odds, after adjusting for the confounders.