Emerging Increase in the prevalence and severity of nonalcoholic fatty liver disease: epidemiological study from general Mediterranean population

Abstract

Background and Aims: The worldwide spread of obesity and diabetes is leading to a drastic increase in nonalcoholic fatty liver disease (NAFLD) and its complications.We aimed to assess prevalence of NAFLD and of its severity among a general Mediterranean population. Methods:We considered 886 consecutive individuals included in the ABCD study (ISRCTN15840340). Hepatic ultrasound (US) was used to diagnose steatosis and FibroScan (M and XL probe) to measure liver stiffness and controlled attenuation parameter (CAP). Liver stiffness >6.9 KPa was considered suggestive of significant liver fibrosis (Petta S et al., Hepatology 2015), and CAP ≥ 310 dB was considered suggestive of moderate-severe steatosis (de Ledinghen V et al., JHEP 2014). Results: Steatosis by USwas diagnosed in 396 individuals (44.6%) and was significantly associated with male gender, type 2 diabetes, low HDL (<40 mg/mL in males and <50 mg/mL in females), and visceral obesity. When splitting the analysis according to gender, steatosis was independently linked to visceral obesity (OR 2.63, 95% CI 1.62– 4.27, p < 0.001) and low HDL (OR 2.06, 95% CI 1.10–3.85, p = 0.02) in males, and to visceral obesity (OR 2.75, 95% CI 1.80–4.19, p < 0.001) and type 2 diabetes (OR 2.19, 95% CI 1.00–4.87, p = 0.05) in females. The rate of US steatosis, stiffness >6.9 kPa and CAP ≥310 progressively increased from males without obesity and low HDL (35.1% steatosis; among theme 18.6% CAP ≥310, and 13.5% stiffness >6.9), to those with one risk factor (from 57.7% to 62.1% steatosis; among them 42.8% CAP ≥310, and from 21.4% to 23.2% stiffness >6.9), and further to those with both risk factors (74.2% steatosis; among them 35% CAP ≥310, and 30% stiffness >6.9). Similarly, in females the rate of US steatosis, stiffness >6.9 kPa and CAP ≥310 progressively increased from patients without obesity and diabetes (23.7% steatosis; among them 6.1% CAP ≥310, and 6.1% stiffness >6.9), to those with only one risk factor (from 33.3% to 50.8% steatosis; among them CAP ≥310 from 30.5% to 54.5%, and stiffness >6.9 from 11.1% to 27.2%), and further to those with both risk factors (74.2% steatosis; among them 47.1% CAP ≥ 310, and 26.4% stiffness >6.9). Conclusions: NAFLD is present in more than 40% of general population and its prevalence, as well as the prevalence of liver