Acta Neurol Scand 1997: 95: 81-84 Printed in UK zyxwvutsrqpo - all rights reserved Copyright zyxw 0 Munksgaard 1997 zy ACTA NEUROLOGICA SCANDINAVICA ISSN 0001-6314 zyx Category fluency is also predominantly affected in Swiss Alzheimer's disease patients Monsch AU, Seifritz E, Taylor KI, Ermini-Funfschilling D, Stahelin HB, Spiegel zyxwvutsr GFEDCBA R. Category fluency is also predominantly affected in Swiss Alzheimer's disease patients. Acta Neurol Scand 1997 95: 81-84. zyxwvut GFEDCBA 0 Munksgaard 1997. Objectives - To establish the comparative efficacy to differentiate between Swiss patients with dementia of the Alzheimer type (DAT) and elderly normal control subjects (NC) on two different verbal fluency tasks: category fluency and letter fluency. Material and methods - Fifty Swiss German DAT patients in the early stages of the disease and 50 matched normal control subjects were compared on letter and category fluency tasks. Results - DAT patients exhibited an overproportional impairment on category fluency as compared with letter fluency. Receiver operating characteristic curves (ROC) showed that category fluency correctly classified a significantly higher number of DAT patients and NC subjects (84%) than letter fluency (70%). Conclusion - As similar findings have been described for English-speaking DAT patients, we conclude that deficiencies in category fluency are a general phenomenon, reflecting impaired structures of semantic knowledge occurring early in the course of Alzheimer's disease. Previous research has demonstrated that patients with dementia of the Alzheimer type (DAT) are significantly impaired on verbal fluency tasks (1- 6). Moreover, a recent study found that category fluency performance (i.e., the ability to generate exemplars of a given category) is overpropor- tionally impaired compared to letter fluency (i.e., generating words beginning with a given letter) (7). This pattern of impairment has been attributed to a breakdown in the structure of semantic knowl- edge. Since these previous studies were conducted using native English-speaking subjects, the gener- alizability of these findings to non-native English- speaking subjects is unclear. The present study attempted to replicate the finding of a more pronounced category fluency impairment with Swiss German-speaking DAT patients. Hence, the performances of a sample of early stage DAT patients were compared to those of elderly normal control subjects on category fluency and letter fluency tasks. zyxwv QPONM A. U. Monsch'. E. Seifritzt2, K. 1. Taylop, D. Ermini- Funfschilling', H. B. Stahelin', R. Spiege14 'Memory Clinic, Geriatric University Clinic, Basel, Switzerland, 2Department of Veterans Affairs Medical Center and Department of Psychiatry, School of Medicine, University of California, San Diego, USA, 'University of Zurich, Switzerland, 4DRRA Strategy CNS Group, Sandoz Pharma AG. Basel, Switzerland Key words: verbal fluency: category fluency; letter fluency; Alzheimer's disease: receiver operating characteristic curve Andreas U. Monsch. Memory Clinic, Geriatric University Clinic, Hebelstrasse 10, CH-4031 Basel, Switzerland Accepted for publication November 15, 1996 Material and methods Subjects One hundred subjects participated in this study: 50 outpatients with dementia of the Alzheimer type (DAT) and 50 normal control (NC) subjects were matched painvise on gender, age, and level of education. Chi-square and t-test analyses reveale no differences between these two groups on gend (x2<l), age zyxw NML (t<l), and level of education (t<l). Patients were recruited from an outpatient geriatric referral center (Memory Clinic) at th Geriatric University Clinic in Basel, Switzerland. The patients were referred by internists and fam practitioners in and around Basel to substantiate suspicion of dementia and/or to assist in further medicaVsocia1 management. All DAT patients were diagnosed according to the criteria for p mary degenerative dementia outlined in DSM-11 (8) and by the criteria for probable Alzheimer's disease developed by the National Institute of