Cognitive longitudinal predictors of older adults' self-reported IADL function

Objective: To examine basic and everyday cognitive predictors of older adults' self-reported instrumental activities of daily living (IADL).

Method: Basic and everyday cognitive predictors of self-reported IADL were examined in a sample of healthy, community-dwelling older adults (n = 698) assessed over 5 years of measurement.

Results: Multilevel longitudinal analyses revealed linear and quadratic change trends for self-reported IADL function, with steeper declines at higher ages. Within-person, when participants exhibited lower cognitive performance, they also reported more IADL impairment. Everyday cognition remained a significant unique predictor of self-reported IADL after controlling for attrition, resampling effects, temporal gradients, and baseline levels and changes in demographic, sensory, functional, and basic cognitive measures.

Discussion: By itself, everyday cognition appears to be an important predictor of self-reported IADL, and maintains a unique predictive contribution after many covariates are controlled. Future research should consider the inclusion of everyday cognitive measures in functional assessment batteries.