Diagnostic Precision in the Detection of Mild Cognitive Impairment: A Comparison of Two Approaches

Abstract OBJECTIVE This study compared diagnostic rates and clinical predictors of discrepancies between diagnoses conferred via: 1) a comprehensive neuropsychological evaluation and National Institute on Aging–Alzheimer's Association (NIA-AA) criteria vs. 2) a cognitive screener and Diagnostic Statistical Manual of Mental Disorders (DSM-5) criteria. DESIGN Cross-sectional examination of baseline data from the P revention of Al zheimer's dementia (AD) using C ognitive remediation and t ranscranial direct current stimulation in M CI and D epression (PACt-MD; ClinicalTrials.gov Identifier: NCT02386670) trial. SETTING Five geriatric psychiatry and memory clinics located at academic hospitals affiliated with the Department of Psychiatry, University of Toronto. PARTICIPANTS Older adults (N=431) with a history of major depressive disorder (MDD) in remission, MCI, or both. MEASUREMENTS Main outcome was a comparison of NIA-AA diagnostic rates of MCI or dementia vs. DSM-5 rates of mild or major NCD. Secondary analyses examined demographic, race, gender, premorbid intellectual ability, psychosocial, health-related, and genetic predictors of discrepancy between DSM-5 and NIA-AA diagnoses. RESULTS There were 103 (23.8%) discrepant cases, with most (91; 88.3%) of these discrepant cases reflecting more impairment with the detailed neuropsychological testing and NIA-AA criteria. Discrepancies were more likely in individuals with a history of MDD or who had at least one ApoE4 allele. CONCLUSIONS The NIA-AA criteria, in conjunction with comprehensive neuropsychological testing, identified a greater prevalence of cognitive impairment than the DSM-5 criteria, in conjunction with the MoCA. Detailed neuropsychological evaluations are recommended for older adults who have a history of MDD or a genetic vulnerability to dementia.