Usefulness of p300 in subjective memory complaints: a prospective study.
The existing studies about the utility of P300 latency for diagnostically classifying patients in preclinical stages of dementia are cross-sectional rather than longitudinal in design, and their results are inconclusive. The authors investigated the P300 value in a series of patients with subjective memory complaints using a prospective design. The study was performed in a consecutive series of 116 outpatients with subjective memory complaints as the predominant symptom. P300 (auditory oddball task) was performed immediately after the first clinical evaluation, and at 12 and 24 months. Final cognitive syndrome diagnosis (mean follow-up period, 27.7 months) was then made by a neurologist who was blinded to the neurophysiologic results. Diagnosis at the end of follow-up was 30 cases of normal cognition, 30 cases of mild cognitive impairment, 28 cases of dementia of Alzheimer's type (DAT), five cases of vascular dementia, and one case of frontotemporal dementia; 22 patients were lost to follow-up. P300 latency was significantly higher for the DAT group (analysis of variance: P=0.023) throughout the study. The diagnostic value of P300 latency at baseline examination for DAT had a sensitivity of 52.9% and a specificity of 76.9%; the odds ratio was 3.75 (95% confidence interval, 1.23-11.41). Findings from the present study suggest that assessment of evoked related potentials may contribute to the early detection of DAT.
Gironell
Alexandre
A
Cognitive Disorders Section, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Autonomous University of Barcelona, Spain. agironell@santpau.es
García-Sánchez
Carmen
C
Estévez-González
Armando
A
Boltes
Anunciación
A
Kulisevsky
Jaime
J
D000161:Acoustic Stimulation / Q000379:methods; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000503:physiopathology; D000704:Analysis of Variance; D002491:Central Nervous System Agents / Q000627:therapeutic use; D003704:Dementia / Q000503:physiopathology; D018913:Event-Related Potentials, P300 / Q000187:drug effects / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology*; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011446:Prospective Studies; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology
D002491:Central Nervous System Agents