P2‐308: Longitudinal Changes in Visual Memory in Mild Cognitive Impairment Versus Normal aging in People with Subjective Cognitive Complaint

Resumo

BackgroundPrevious studies have shown that visual memory impairments are important markers for an early diagnosis of Mild cognitive impairment (MCI) in people with subjective cognitive complains. The purpose of this study was to compare longitudinal changes on visual memory performance in individuals complaining of memory deficits and diagnosed with and without MCI.MethodsWe evaluated 209 individuals aged +50 years who attended primary care health centers with subjective cognitive complains and without neurological or psychiatric illness. Each participant underwent extensive evaluation, including review of his or her medical history and neuropsychological assessment and was revaluated up to two times at approximately 15 months intervals with an average follow up time of 3.5 years. Of the 209 individuals 170 were diagnosed as Healthy Controls and 39 as MCI at the third evaluation following standard criteria (Albert et al 2011; Petersen 2004). We compared the trajectory of performance of the two groups on the CANTAB tests, Pattern Recognition Memory (PRM. Percent correct), Delayed Matching to Sample (DMS, percent correct), Spatial Span (SSP, span length) and Paired Associates Learning (PAL, total errors adjusted) using lineal mixed models.ResultsThe Healthy Control group showed a maintained or increased performance on all tests suggesting a practice effect on several processes involved in visual memory such as attention, recognition, recollection, learning and working memory. The MCI group showed a significant decline from baseline to the last evaluation on these visual memory processes.ConclusionsLongitudinal studies add new evidence that the CANTAB tests, PRM, DMS, SSP and PAL are useful for diagnosis of MCI across time in people with subjective cognitive complains. Further longitudinal research is necessary to determine the predictive value of these tests on the conversion to Alzheimer Disease.