Background & Aim Histologic analysis of liver biopsies allows for grading and staging of nonalcoholic fatty liver disease (NAFLD). We performed a longitudinal study to investigate the long-term prognostic relevance of histologic features for patients with NAFLD. Methods We performed a retrospective analysis of 619 patients diagnosed with NAFLD from 1975 through 2005 at medical centers in the United States, Europe, and Thailand. Patients underwent laboratory and biopsy analyses, and were examined every 3–12 months after their diagnosis. Outcomes analyzed were overall mortality, liver transplantation, and liver-related events. Cumulative outcomes were compared by log-rank analysis. Cox proportional-hazards regression was used to estimate adjusted hazard ratios (HR). Time at risk was determined from the date of liver biopsy to the date of outcome or last follow-up examination. Results Over a median follow-up of 12.6 years (range 0.3–35.1), 193 of the patients (33.2%) died or underwent liver transplantation. Features of liver biopsies significantly associated with death or liver transplantation included fibrosis stage 1 (HR, 1.88; 95% CI, 1.28, 2.77), stage 2 (HR, 2.89; 95% CI, 1.93, 4.33), stage 3 (HR, 3.76; 95% CI, 2.40, 5.89), and stage 4 (HR, 10.9; 95% CI, 6.06, 19.62) compared with stage 0, as well as age (HR, 1.07; 95% CI, 1.05, 1.08), diabetes (HR, 1.61; 95% CI, 1.13, 2.30), current smoking (HR, 2.62; 95% CI, 1.67, 4.10) and statin use (HR, 0.32; 95% CI, 0.14, 0.70). Twenty-six patients (4.2%) developed liver-related events; fibrosis stage 3 (HR 14.2 [95% CI 3.38, 59.68]) and stage 4 (HR 51.5 [95% CI 9.87, 269.2]) compared to stage 0, were significantly associated with the events. Patients with fibrosis, regardless of steatohepatitis or NAFLD activity score, had shorter survival times than patients without fibrosis. Conclusions In a longitudinal study of patients with NAFLD, fibrosis stage, but no other histologic features of steatohepatitis, were independently associated with long-term overall mortality, liver transplantation, and liver-related events.

In a systematic review and meta-analysis, Giovanni Musso and colleagues examine the association between non-alcoholic fatty liver disease and chronic kidney disease. Please see later in the article for the Editors' Summary

Objectives: The long-term prognosis of non-alcoholic fatty liver disease (NAFLD) in children remains uncertain. We aimed at determining the long-term outcomes and survival of children with NAFLD. Design: Retrospective longitudinal hospital-based cohort study. Patients: Sixty-six children with NAFLD (mean age 13.9 (SD 3.9) years) were followed up for up to 20 years with a total of 409.6 person-years of follow-up.