Nonalcoholic Fatty Liver Disease Isn’t Associated with Excess Mortality


The same was true for nonalcoholic steatohepatitis.

Nonalcoholic fatty liver disease (NAFLD) is associated with cirrhosis, liver cancer, and several cardiovascular (CV) risk factors such as diabetes and obesity. Prior studies, however, have not established a clear association between NAFLD and early mortality, and most of these studies were based on highly selected patient populations (e.g., those with biopsy-proven NAFLD). To assess this association, researchers conducted a prospective cohort study based on data from the Third National Health and Nutrition Examination Survey (1988–1994), which involved more than 11,000 adults (age range, 20–74) who underwent baseline hepatic ultrasonography.

NAFLD was defined as “the presence of moderate to severe hepatic steatosis with normal liver enzyme levels.” Nonalcoholic steatohepatitis (NASH) was defined as “the presence of moderate to severe hepatic steatosis with increased levels of liver enzymes,” without evidence of hepatitis B or C infection or iron overload. The prevalence of NAFLD was 16%, the prevalence of NASH was 3%, and median follow-up was 14.5 years. Neither NAFLD nor NASH was associated with elevated all-cause mortality or death from CV disease, cancer, or liver disease. These outcomes were noted both in analyses that were adjusted for CV risk factors and in those that were not.

Comment: In this large prospective study, NAFLD and NASH were not associated with elevated risk for all-cause mortality or death from CV disease, cancer, or liver disease. However, these results should be interpreted with some caution, in part because the authors had to create their own ultrasound- and laboratory-based definitions. Although ultrasonography accurately detects hepatic steatosis, ultrasound-detected hepatic steatosis combined with elevated liver enzymes has limited sensitivity and specificity for NASH. The authors call for further studies with large samples and more-refined diagnostic methods to determine the effects of NASH on mortality.

Source: Journal Watch General Medicine.