Cognitive impairment is common in patients with advanced liver disease. It has been suggested that patients with alcoholic liver disease (ALD) have more impaired cognition than nonalcoholics. The objective of this study was to characterize any differences in cognitive functions between alcoholic cirrhotic patients and non-alcoholic cirrhotic patients of similar age, education, and severity of liver disease. We assessed cognitive functions in 117 patients with alcoholic cirrhosis and 163 patients with nonalcoholic cirrhosis using a brief battery of neuropsychological tests. In addition, all patients had standard psychiatric examinations to assess the effect of the disease severity, alcoholism, anxiety, and depression on the test scores. The study showed a higher proportion of patients with cognitive impairment in the alcoholic group. Alcoholics performed poorly in tests of memory and motor speed compared with nonalcoholics, despite similar premorbid IQ and education. Because patients with alcoholic cirrhosis had more severe liver disease (Child-Pugh score 8.5 Ψ 2.2 vs. 7.6 Ψ 2.2, P β«Ψβ¬ .03) than nonalcoholics, the results were reanalyzed after adjusting for the linear effects of Child-Pugh score on cognitive test scores. We also used two-way analysis of variance to examine the interaction between Child class and alcoholism. Finally, the test scores were compared within each Child class. These analyses revealed no primary or interaction effect of alcoholism and confirmed that the differences in the test scores observed in alcoholics reflect the greater severity of their liver disease. The severity of cognitive impairment is similar in both alcoholic and non-alcoholic cirrhotic patients when adjusted for the severity of liver disease. (HEPATOLOGY 1999;30:1363-1367.