Greater baseline intra-individual variation in telephone-based cognitive screening predicts cognitive and diagnostic outcomes at 2-year follow-up.

Objective: Intra-Individual Cognitive Variability (IICV) is an emerging clinical tool that has shown promise in predicting cognitive decline and dementia incidence. The present study aims to assess the predictive validity of IICV in remote cognitive screening tests, using nationally representative data.

Method: Two waves of cognitive and diagnostic data from the Health and Retirement Study (collected in 2010 and 2012) were utilized to investigate whether baseline IICV can predict cognitive decline and dementia pathology. Middle-aged and older adults who were cognitively intact and completed all cognitive tests at both baseline and follow-up were recruited in the study, resulting in a sample of 6,050 participants. With the coefficient of variation method, the IICV-dispersion was calculated based on cognitive screeners to predict follow-up mean cognitive performance, global cognition, suspected cognitive impairment, and self-reported dementia diagnosis.

Results: After accounting for demographics, depressive symptoms, and baseline cognitive performance, the results provide support for the predictive validity of IICV. Specifically, the study demonstrated that IICV-dispersion significantly predicted cognitive and diagnostic outcomes in a concave pattern where the prediction was more sensitive toward the higher end of IICV. IICV explained about 0.2%-2.3% of the variance of outcomes variables.

Conclusions: IICV retrieved from cognitive screening tests in telemedicine settings offers insight into future cognitive functioning and neurocognitive diagnostic status, which can be cost-effective and reduce the burden on both patients and health care providers, especially benefitting individuals with low socioeconomic status and rural residents. Potential avenues for future research were also discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).