Nonalcoholic fatty liver disease (NAFLD): is it really a serious condition?

Abstract

OBJECTIVE: To evaluate the association between non-alcoholic fatty liver disease and all cause and cause specific mortality in a representative sample of the US general population.

DESIGN: Prospective cohort study.

SETTING: US Third National Health and Nutrition Examination Survey (NHANES III: 1988–94) with follow-up of mortality to 2006.

PARTICIPANTS: 11,371 adults aged 20–74 participating in the Third National Health and Nutrition Examination Survey, with assessment of hepatic steatosis.

MAIN OUTCOME MEASURE: Mortality from all causes, cardiovascular disease, cancer, and liver disease (up to 18 years of follow-up).

RESULTS: The prevalence of non-alcoholic fatty liver disease with and without increased levels of liver enzymes in the population was 3.1% and 16.4%, respectively. Compared with participants without steatosis, those with non-alcoholic fatty liver disease but normal liver enzyme levels had multivariate adjusted hazard ratios for deaths from all causes of 0.92 (95% confidence interval 0.78 to 1.09), from cardiovascular disease of 0.86 (0.67 to 1.12), from cancer of 0.92 (0.67 to 1.27), and from liver disease of 0.64 (0.12 to 3.59). Compared with participants without steatosis, those with non-alcoholic fatty liver disease and increased liver enzyme levels had adjusted hazard ratios for deaths from all causes of 0.80 (0.52 to 1.22), from cardiovascular disease of 0.59 (0.29 to 1.20), from cancer of 0.53 (0.26 to 1.10), and from liver disease of 1.17 (0.15 to 8.93).

CONCLUSIONS: Non-alcoholic fatty liver disease was not associated with an increased risk of death from all causes, cardiovascular disease, cancer, or liver disease

BACKGROUND & AIMS: The relative frequency of nonalcoholic steatohepatitis (NASH) as an indication for liver transplantation and comparative outcomes following transplantation are poorly understood.

METHODS: We analyzed the Scientific Registry of Transplant Recipients for primary adult liver transplant recipients from 2001 to 2009.

RESULTS: From 2001 to 2009, 35,781 patients underwent a primary liver transplant, including 1959 for who NASH was the primary or secondary indication. The percentage of patients undergoing a liver transplant for NASH increased from 1.2% in 2001 to 9.7% in 2009. NASH is now the third most common indication for liver transplantation in the United States. No other indication for liver transplantation increased in frequency during the study period. Compared with other indications for liver transplantation, recipients with NASH are older (58.5±8.0 vs 53.0±8.9 years; P<.001), have a larger body mass index (>30 kg/m2) (63% vs 32%; P<.001), are more likely to be female (47% vs 29%; P<.001), and have a lower frequency of hepatocellular carcinoma (12% vs 19%; P<.001). Survival at 1 and 3 years after liver transplantation for NASH was 84% and 78%, respectively, compared with 87% and 78% for other indications (P=.67). Patient and graft survival for liver recipients with NASH were similar to values for other indications after adjusting for level of creatinine, sex, age, and body mass index.

CONCLUSIONS: NASH is the third most common indication for liver transplantation in the United States and is on a trajectory to become the most common. Outcomes for patients undergoing a liver transplant for NASH are similar to those for other indications