Nonalcoholic Fatty Liver Disease Associates With Increased Overall Mortality and Death From Cancer, Cardiovascular Disease, and Liver Disease in Women but Not Men

Abstract

BACKGROUND & AIMS: It is not clear whether women vs men have increased mortality from nonalcoholic fatty liver disease (NAFLD). We investigated whether NAFLD is associated with increased overall and cause-specific deaths in a Korean population using a large health study database. METHODS: We collected data on 318,224 subjects in Korea (165,131 men and 153,093 women) age 20 to 94 years (mean age, 39.3 y), enrolled in the Kangbuk Samsung Health Study cohort. All subjects underwent a comprehensive annual or biennial health examination in Seoul or Suwon, South Korea, from 2002 through 2012. The presence of NAFLD was ascertained by ultrasonography in the absence of other known liver diseases. Mortality (from 2002 through 2012) was determined by the nationwide death certificate data from the Korea National Statistical Office. RESULTS: During a median 5.7-year follow-up period, cumulative overall mortality was 0.51% (1613 deaths)-cancer was the leading cause of death. In men, NAFLD was not associated with increased mortality from any cause, except lower rate of death from cancer (hazard ratio, 0.79; 95% CI, 0.66-0.93; P = .005), after adjusting for age, body mass index, smoking status, daily alcohol consumption, and physical activity. In women, NAFLD was independently associated with death from all causes (hazard ratio, 1.79; 95% CI, 1.50-2.14; P <.0001), death from cancer (hazard ratio, 1.83; 95% CI, 1.42-2.35; P <.0001), death from cardiovascular disease (hazard ratio, 1.63; 95% CI, 1.00-2.66; P =. 0498), and death from liver disease (hazard ratio, 5.58; 95% CI, 1.79-17.39; P = .003). In obese men, NAFLD was associated with a reduced risk of death from cancer. However, NAFLD was associated with increased risk of death from cardiovascular disease in nonobese men. In obese women, NAFLD did not increase risk of death compared with obesity alone. However, NAFLD was associated with increased overall risk of death and risk of death from cancer in nonobese women. CONCLUSIONS: Associations between NAFLD and mortality differ between men and women in Koreans. NAFLD was associated with increased overall mortality and death from cancer, cardiovascular disease, and liver disease in women, but these associations were not observed in men.