Ethnic differences in the prevalence of cryptogenic cirrhosis

OBJECTIVES: Nonalcoholic steatohepatitis (NASH) associated with obesity and type 2 diabetes mellitus (DM) is postulated to be the cause of most cases of cryptogenic cirrhosis (CC). While ethnic differences in the prevalence of obesity and DM in the United States are well documented, there is little information regarding prevalence of CC or NASH among different U.S. ethnic groups. This study was performed to assess the demographic characteristics of patients with CC at a U.S. county hospital with a racially and ethnically diverse patient population. METHODS: Medical records and pathology databases were reviewed to identify patients at Parkland Memorial Hospital, Dallas County, Texas from 1990 to 2001 with CC or cirrhosis attributed to NASH. RESULTS: Forty-one patients (12 men, 29 women) were found to meet these criteria. Of these, 68% were obese (BMI greater than or equal to 30) and/or had type 2 DM and 74% of liver biopsies revealed one or more features of NASH. Of patients with CC 68% were Hispanic while only 7% were African American, despite the fact that Hispanics comprised <26% and African Americans >40% of adult medicine patients. Prevalence of CC among Hispanic and African American patients was 3.1-fold higher and 3.9-fold lower, respectively, than among European American patients despite similar prevalence of DM among Hispanics and African Americans. CONCLUSION: These findings support the hypothesis that NASH associated with obesity and DM is responsible for the majority of cases of CC among Hispanics and European Americans. However, the current findings also indicate that this form of cirrhosis is unexpectedly rare among African Americans.