Associations Between Liver Histology and Severity of the Metabolic Syndrome in Subjects With Nonalcoholic Fatty Liver Disease MARNO C. RYAN, MBBS, FRACP 1,2 ANDREW M. WILSON, MBBS, FRACP 2 JOHN SLAVIN, MBBS, FRACP 3 JAMES D. BEST, MD, FRACP 2 ALICIA J. JENKINS, MD, FRACP 2 PAUL V. DESMOND, MD, FRACP 1,2 N onalcoholic fatty liver disease (NAFLD) is associated with a his- topathological picture resembling alcohol-induced liver injury occurring in subjects who consume insignificant amounts of alcohol. In NAFLD, steatosis alone is associated with good prognosis, whereas nonalcoholic steatohepatitis (NASH) can progress to fibrosis and cir- rhosis in up to 30% of cases, potentially leading to liver failure and hepatocellular carcinoma. The prevalence of NAFLD and NASH in the U.S. is estimated at 10 –20 and 2–3%, respectively (1–3). The metabolic syndrome, as defined by Adult Treatment Panel (ATP) III crite- ria, incorporates features known to pre- dict cardiovascular disease and type 2 diabetes (4). NAFLD has been demon- strated to be associated with features of the metabolic syndrome, including hy- perglycemia (5,6), dyslipidemia (5,6), hy- pertension (7), and central obesity (7,8). In addition, insulin resistance, even with- out these other features, is almost univer- sal in subjects with NAFLD (6). However, the factors specifically associated with he- patic inflammation, fibrosis, and thus liver disease progression are still being elucidated. In this study of human subjects with NAFLD, we explored specific relation- ships between hepatic histology and markers of the metabolic syndrome. RESEARCH DESIGN AND METHODS — Forty-six subjects with NAFLD were recruited from clinics. The diagnosis was based on the histological presence of macrovesicular steatosis, with or without lobular inflammation, hepato- cellular degeneration, or fibrosis (8,9). All subjects were negative for viral hepatitis, anti-nuclear antibody, anti–smooth mus- cle antibody, and anti-mitochondrial an- tibody and had normal iron and copper studies. All subjects consumed 14 stan- dard drinks of alcohol per week (9). Nine male subjects and eight female subjects had preexisting type 2 diabetes, five man- aged their diabetes with diet alone, and 12 were taking metformin. Approval for the study was obtained from the institutional research ethics committee, and written informed consent was obtained. Adiposity was assessed with BMI and dual-energy X-ray absorptiometry (DEXA) (Lunar DPX-L; Lunar, Madison, WI). Metabolic syndrome was defined by ATP III criteria (10). Each subject and their respective control was given a score of 1 for each feature of the metabolic syn- drome, for a maximum score of 5, with a score of 3 being diagnostic of the meta- bolic syndrome (10). Insulin resistance was estimated using the homeostasis model assessment (HOMA) for insulin re- sistance score with fasting insulin and glucose levels (11). A pathologist blinded to subject details scored liver biopsies, al- lotting a score from 0 to 4 for inflamma- tion, steatosis, and fibrosis as previously described (12). For additional fibrosis as- sessment, all biopsies were stained with Masson’s Trichrome, percent fibrosis was calculated in triplicate by microscopy and image analysis (AIS, Toronto, ON, Can- ada), and data were expressed as mean percentages. Continuous variables were log n transformed, and correlations were assessed by Pearson’s correlations and stepwise regression. Correlations with categorical variables were analyzed using Spearman correlations. A P value 0.05 was considered statistically significant. RESULTS — Liver histopathology re- sults were steatosis alone (10 subjects), NASH with fibrosis score of 0 (12 subjects), NASH/fibrosis score 1 (14 subjects), NASH/ fibrosis score 2 (5 subjects), and NASH/ fibrosis score 3 (5 subjects). None had cirrhosis (a score of 4 for fibrosis). Hepatic steatosis was associated with BMI (r = 0.36, P = 0.02) and percentage trunk fat measured by DEXA (r = 0.3, P = 0.05). Hepatic inflammation was only significantly associated with BMI (r = 0.35, P = 0.02), and hepatic fibrosis was not correlated with any measure of adiposity. However, there were significant asso- ciations seen between hepatic inflamma- tion, fibrosis, and features of the metabolic syndrome. Both inflammation and fibrosis correlated significantly with serum insulin, HOMA for insulin resis- tance, and ATP III score. Other measures of the metabolic syndrome analyzed indi- vidually did not correlate with hepatic fi- brosis. The two measures of fibrosis ●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●● From the 1 Department of Gastroenterology, St. Vincent’s Hospital, Fitzroy, Australia; the 2 Department of Medicine, University of Melbourne, Parkville, Australia; and the 3 Department of Pathology, St. Vincent’s Hospital, Fitzroy, Australia. Address correspondence and reprint requests to Dr. Marno C. Ryan, Department of Medicine, 4th Floor Clinical Sciences Building, St. Vincent’s Hospital, 41 Victoria Parade, Fitzroy 3065 Victoria, Australia. E-mail: marno.ryan@svhm.org.au. Received for publication 20 January 2005 and accepted 23 January 2005. Abbreviations: ATP, Adult Treatment Panel; DEXA, dual-energy X-ray absorptiometry; HOMA, ho- meostasis model assessment; NAFLD, nonalcoholic fatty liver disease; NASH, nonalcoholic steatohepatitis. A table elsewhere in this issue shows conventional and Syste `me International (SI) units and conversion factors for many substances. © 2005 by the American Diabetes Association. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. Metabolic Syndrome/Insulin Resistance Syndrome/Pre-Diabetes B R I E F R E P O R T 1222 DIABETES CARE, VOLUME 28, NUMBER 5, MAY 2005