Objective cognitive performance and informant‐rated dysexecutive symptoms in mild cognitive impairment and Alzheimer’s disease

Abstract

AbstractBackgroundOlder adults with mild cognitive impairment (MCI) and Alzheimer’s disease (AD) often exhibit memory and executive deficits on objective cognitive tests. Meanwhile, significant others often report observing symptoms of a dysexecutive nature while labeling them as “memory” difficulties. Our study examined whether objective test performances were predictive of informant‐rated executive symptoms in healthy aging, MCI, and AD.MethodParticipants included healthy older controls (n=71), individuals with MCI [n=98 (amnestic MCI n=52; non‐amnestic MCI n=43)], and persons with AD (n=40). Objective cognitive performances were measured using a standardized executive composite (Trail Making Test B and Stroop Color‐Word Interference) and a standardized memory composite (delayed recall scores from the California Verbal Learning Test‐II and Visual Reproduction‐II). Study partners completed the Dysexecutive Questionnaire (DEX), which assesses executive behaviors and symptoms.ResultMultiple regression analyses revealed that objective memory performance predicted informant‐rated dysexecutive symptoms in the AD group and in the MCI group as a whole. In contrast, objective executive performance did not predict DEX scores in any of the groups. As expected, objective cognitive performance and DEX scores were not significantly associated in the control group.ConclusionInterestingly, we found that objective memory performance predicted informant‐rated dysexecutive symptoms in MCI and AD, while objective executive performance did not. This finding suggests that in everyday life, patient behaviors labeled as “dysexecutive” may be driven by memory deficits. For example, the DEX reviews behaviors that involve attentional difficulties and perseverative thinking, which can be assessed in both memory and executive tests. Overall, these findings underline the importance of integrating objective test performance with reports of patient symptoms in the real world.