Prevalence of primary non‐alcoholic fatty liver disease in a population‐based study and its association with biochemical and anthropometric measures

Background/Aims: Only a few studies have assessed the epidemiology of non‐alcoholic fatty liver disease (NAFLD). The aim was to evaluate the prevalence of primary NAFLD in a population‐based study in Israel and to determine independent risk factors. Methods: A cross‐sectional study of a subsample of the Israeli national health survey ( n =352). Individuals with a known etiology for secondary NAFLD were excluded. Each participant underwent an abdominal ultrasound, biochemical tests and an anthropometric evaluation. Results: Three hundred and twenty‐six subjects (53.4% male, mean age 50.5±10.3 standard deviaton [SD]) met the inclusion criteria. The prevalence of primary NAFLD was 30% (25–35% 95% confidence intervals [CI]). NAFLD was more prevalent in men than women (38% vs. 21%; P =0.001). Compared with ultrasonography, the sensitivity of serum alanine transaminase ( ALT) for the diagnosis of primary NAFLD was 8.2%. Risk factors independently associated with NAFLD included male gender (odds ratios (OR)=2.8, 95% CI 1.5–5.3), abdominal obesity (OR=2.9, 95% CI 1.3–6.4), homeostasis model assessment (OR=5.8, 95% CI 2.0–17.2), hyperinsulinemia (OR=2.3, 95% CI 1.2–4.3, P =0.01) and hypertriglyceridemia (OR=2.4, 95% CI 1.3–4.5). Conclusions: NAFLD is prevalent in the general Israeli population and closely related to the metabolic syndrome. The use of ALT as a marker for NAFLD seriously underestimates its prevalence.