Mild Cognitive Impairment Due to Alzheimer Disease is Less Likely Under the Age of 65.

Mild Cognitive Impairment Due to Alzheimer Disease is Less Likely Under the Age of 65. Alzheimer Dis Assoc Disord. 2014 Apr 22; Authors: Shin S, Kim JH, Cho JH, Kim GS, Choi SA, Lee JH, For the Alzheimer’s Disease Neuroimaging Initiative Abstract Patients with amnestic mild cognitive impairment (aMCI) are considered to have a high risk for Alzheimer dementia (AD). Even high positive predictive values, however, cannot be guaranteed even by tests with high sensitivity and specificity when disease prevalence is low. If we regard the clinical criteria for aMCI as a test for predicting aMCI due to AD, the positive predictive value of the criteria will be low by definition in young patients with aMCI (age below 65 years) because of the low prevalence of AD in this age group. To test this hypothesis, we compared CSF biomarkers for AD between young (age below 65 years) and old (age 65 years or older) age groups of normal cognition, aMCI, and AD of the Alzheimer's Disease Neuroimaging Initiative database. Using these biomarkers, we observed that the prevalence of aMCI due to AD differed significantly between the young and the old. For example, only 28.2% young aMCI, but 63.2% old aMCI, had abnormal CSF amyloid measures consistent with AD pathology. As posited, the presence of aMCI due to AD was lower in young aMCI than in old aMCI. Given that the likelihood of aMCI due to AD is reduced in younger subjects, more attention to and evaluation o...
Source: Alzheimer Disease and Associated Disorders - Category: Psychiatry Tags: Alzheimer Dis Assoc Disord Source Type: research