Background: Dementia caused by Alzheimer’s disease (AD) commonly affects the adult population with Down’s syndrome (DS). However, AD diagnosis represents a diagnostic challenge due to the intellectual disability associated with DS and to a lack of appropriate instruments. Methods: Prospective longitudinal 3 year cohort study. Forty-four healthy DS were recruited from the Down Medical Centre. We included only subjects with mild or moderate intellectual disability (ID) (DSM-IV and ICD-10 criteria). Subjects with cognitive and/or functional decline at baseline were excluded. Subjects underwent annual neuropsychological assessments using CAMCOG-DS. An evaluation for progression to AD was performed blinded to CAMCOG-DS scores. Results: Mean age at baseline was 38.8 years (SD 10.14). Twenty-seven patients were males (61.4%). Eighteen patients had mild ID (40.9%). CAMCOG-DS scores at baseline were related to severity of ID, but were not related to gender (p ¼ 0.43) or age (p ¼ 0.57). Subjects with mild ID scored higher on the total CAMCOG-DS score at baseline than patients with moderate ID (mean 83.9 vs 68.7; p < 0.001). At follow up, 10 patients developed AD dementia. The repeated longitudinal CAMCOG-DS evaluation in those subjects who progressed to AD dementia revealed an accelerated rate of change in total CAMCOG-DS scores (mean change after 1, 2 and 3 years was -9.6, -12.33 and -22.4, respectively). Memory, language and visual perception were the earliest cognitive domains affected. In healthy DS subjects, total CAMCOG-DS scores remained stable. When stratifying by age (< 40 and 40 years), only scores on memory CAMCOG-DS subscale declined significantly in older healthy DS patients. Conclusions: CAMCOG-DS is a sensitive neuropsychological battery to assess cognitive decline in DS patients who progress to dementia. However, cross-sectional CAMCOG-DS scores depend greatly on severity of ID. Therefore, for AD diagnosis in DS subjects, individual longitudinal change should be used.
Benejam, B., Videla, L., Fernández, S., Carmona-Iragui, M., Videla, S., & Fortea, J. (2014). P4-320: NEUROPSYCHOLOGICAL ASSESSMENT OF ADULTS WITH DOWN SYNDROME USING THE CAMCOG-DS: A LONGITUDINAL COHORT STUDY. Alzheimer’s & Dementia, 10, P903–P903. https://doi.org/10.1016/j.jalz.2014.07.091