Type 2 diabetes mellitus: A risk factor for progression of liver fibrosis in middle-aged patients with non-alcoholic fatty liver disease

Background and Aim The severity of liver fibrosis is strongly associated with prognosis in patients with non-alcoholic fatty liver disease (NAFLD). We evaluated clinical risk factors for progression of liver fibrosis in patients with NAFLD. Methods This study included 1562 middle-aged (36-64 years) patients with NAFLD and less severe liver fibrosis (fibrosis-4 index < 1.3). Results During follow-up, 186 patients progressed to advanced fibrosis (fibrosis-4 index > 2.67). The 3-, 5-, 7-, and 10-year cumulative incidence of progression to advanced fibrosis was 4.4%, 6.7%, 11.0%, and 16.7%, respectively. In the univariate analysis, age, albumin concentration, and type 2 diabetes mellitus (T2DM) were significantly associated with progression to advanced fibrosis. Multivariate analysis with adjustment for age, smoking, body mass index, albumin, estimated glomerular filtration rate, dyslipidemia, T2DM, and steatosis showed that age >= 50 years (hazard ratio [HR], 2.121; 95% confidence interval [CI], 1.462-3.076; P < 0.001), albumin concentration < 4.2 g/dL (HR, 1.802; 95% CI, 1.285-2.528; P < 0.001), and the presence of T2DM (HR, 1.879; 95% CI, 1.401-2.520; P < 0.001) were independently associated with progression to advanced fibrosis. Conversely, degree of steatosis was not associated with progression to advanced fibrosis. The respective 3-, 5-, 7-, and 10-year cumulative incidence of progression to advanced fibrosis was 3.6%, 5.0%, 8.2%, and 12.9% in patients without T2DM (n = 1077) and 6.1%, 10.4%, 16.7%, and 24.0% in patients with T2DM (n = 485) (P < 0.001). Conclusions Type 2 diabetes mellitus is associated with progression to advanced liver fibrosis in middle-aged NAFLD patients, even those with less severe liver fibrosis.