title: Prevalence of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis among a largely middle-aged population utilizing ultrasound and liver biopsy: a prospective study.
abstract: OBJECTIVE
  Prevalence of nonalcoholic fatty liver disease (NAFLD) has not been well established. The purpose of this study was to prospectively define the prevalence of both NAFLD and nonalcoholic steatohepatitis (NASH).
  
  
  METHODS
  Outpatients 18 to 70 years old were recruited from Brooke Army Medical Center. All patients completed a baseline questionnaire and ultrasound. If fatty liver was identified, then laboratory data and a liver biopsy were obtained.
  
  
  RESULTS
  Four hundred patients were enrolled. Three hundred and twenty-eight patients completed the questionnaire and ultrasound. Mean age (range, 28-70 years) was 54.6 years (7.35); 62.5% Caucasian, 22% Hispanic, and 11.3% African American; 50.9% female; mean body mass index (BMI) (calculated as kg/m(2)) was 29.8 (5.64); and diabetes and hypertension prevalence 16.5% and 49.7%, respectively. Prevalence of NAFLD was 46%. NASH was confirmed in 40 patients (12.2% of total cohort, 29.9% of ultrasound positive patients). Hispanics had the highest prevalence of NAFLD (58.3%), then Caucasians (44.4%) and African Americans (35.1%). NAFLD patients were more likely to be male (58.9%), older (P = .004), hypertensive (P < .00005), and diabetic (P < .00005). They had a higher BMI (P < .0005), ate fast food more often (P = .049), and exercised less (P = 0.02) than their non-NAFLD counterparts. Hispanics had a higher prevalence of NASH compared with Caucasians (19.4% vs 9.8%; P = .03). Alanine aminotransferase, aspartate aminotransferase, BMI, insulin, Quantitative Insulin-Sensitivity Check Index, and cytokeratin-18 correlated with NASH. Among the 54 diabetic patients, NAFLD was found in 74% and NASH in 22.2%.
  
  
  CONCLUSIONS
  Prevalence of NAFLD and NASH is higher than estimated previously. Hispanics and patients with diabetes are at greatest risk for both NAFLD and NASH.
authors.affiliation: Gastroenterology and Hepatology Service, Department of Medicine, Brooke Army Medical Center, Fort Sam Houston, Texas 78234, USA.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Williams
authors.forename: Joel
authors.initials: J
authors.lastname: Stengel
authors.forename: Michael I
authors.initials: MI
authors.lastname: Asike
authors.forename: Dawn M
authors.initials: DM
authors.lastname: Torres
authors.forename: Janet
authors.initials: J
authors.lastname: Shaw
authors.forename: Maricela
authors.initials: M
authors.lastname: Contreras
authors.forename: Cristy L
authors.initials: CL
authors.lastname: Landt
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Harrison
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D001219:Aspartate Aminotransferases / Q000097:blood; D015992:Body Mass Index; D002986:Clinical Trials as Topic; D015331:Cohort Studies; D003920:Diabetes Mellitus / Q000453:epidemiology; D015444:Exercise; D057140:Fast Foods / Q000706:statistics & numerical data; D005234:Fatty Liver / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000201:enzymology / Q000453:epidemiology* / Q000473:pathology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D007328:Insulin / Q000097:blood; D008099:Liver / Q000000981:diagnostic imaging / Q000201:enzymology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease; D015995:Prevalence; D011446:Prospective Studies; D014463:Ultrasonography
chemical_list: D007328:Insulin; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase