P2-124: The correlation of the CDR and the IQCODE in a post-mortem study

Abstract

A variety of tools have been created to evaluate the cognitive performance. Two of the most used scales are the Clinical Dementia Rating Scale (CDR) and the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). To compare the scores of CDR and IQCODE obtained in a post–mortem retrospective study. A post–mortem retrospective study evaluating patients aged 50 or more years, included in the Aging Brain Project from University of São Paulo, São Paulo, Brazil. The cognitive evaluation was gathered using the CDR (Burke and cols 1988) staging cognitive impairment in five levels: CDR 0 (normal), CDR 0.5 (questionable), CDR 1 (mild impairment), CDR 2 (moderate impairment) and CDR 3 (severe impairment); and the IQCODE (Jorm e cols, 1989, 1991) both assessed retrospectively by interview with a knowledgeable informant. A population of 801 patients was enrolled. The mean values of the IQCODE obtained for different CDR stages were: 3.00 for CDR 0 (558 patients); 3.21 for CDR 0.5 (88 patients); 3.55 for CDR 1 (52 patients); 4.10 for CDR 2 (45 patients) and 4.72 for CDR 3 (58 patients), p<0.001. Among the patients who had an IQCODE value between 3.00 and 3.12, 93.4% were classified as CDR 0 and among the patients who had an IQCODE value of 4.00 or higher, 94.8% were classified as CDR 3. When assessed retrospectively in a post–mortem study, the CDR and the IQCODE showed a strong correlation for the evaluation of cognitive status.