Race and comorbid factors predict nonalcoholic fatty liver disease histopathology in severely obese patients

PURPOSE: Nonalcoholic fatty liver disease (NAFLD) is a common and potentially serious form of chronic liver disease. Although NAFLD is known to be associated with obesity and some comorbid conditions, less is known about the severity of NAFLD among different racial groups. METHODS: We prospectively studied 237 consecutive morbidly obese patients presenting for bariatric surgery. All patients underwent intraoperative liver biopsy and chart review. After excluding subjects who reported alcohol use (n = 37) or who had missing biopsy data (n = 11), 189 patients were available for analysis. Clinical and laboratory associations with each of the histological components of NAFLD were assessed using multiple logistic regression analysis. RESULTS: The mean age was 43.1 years, 84% were female, and 13% were African American. It was found that 88% had steatosis, including 35% with moderate to severe steatosis (> 33% of hepatocytes involved). Of these patients, 67% had inflammation, 46% had fibrosis, and 45% met Brunt's criteria for NASH. Compared with Caucasians and after adjustment, African Americans had significantly lower odds of severe hepatic pathology, with adjusted odds ratios of 0.1 (P = .02) for the presence of moderate or severe steatosis, 0.2 for inflammation (P = .006), 0.3 for fibrosis (P = .05), and 0.2 for NASH (P = .02). In addition, participants with one or more features of the metabolic syndrome (ie, diabetes, hypertension, or dyslipidemia) or elevated aminotransferase levels had significantly higher odds of severe hepatic histopathology. CONCLUSION: Among obese patients presenting for bariatric surgery, NAFLD is more common in Caucasians, patients with features of the metabolic syndrome, and those with elevated aminotransferase levels.