A-125 Sex Moderates the Positive Effects of Sleep Schedule Consistency on Cognitive Function

Abstract

Abstract Objective: Negative effects of reduced sleep duration and consistency on cognition are well-known. It is also well-known that both decline with age. While emerging research finds that sex interacts with sleep duration, less is known about whether sex interacts with sleep schedule consistency to predict cognitive performance. We hypothesized that reduced sleep consistency would negatively impact cognitive performance and that women would be less affected by inconsistent sleep based on suggested protective effects of brain organization in sleep-deprived women (Corsi-Carbrera et al., 2003). Methods: Participants (N = 77, 96.3% White) were selected from a parent study of community-dwelling older adults. Inclusion criteria: complete demographic data, Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) index scores, and self-reported sleep data. The sample was majority female and well-educated. Results: RBANS performance and sleep measures were within normal limits (see Table). There was a significant main effect of sleep consistency across all RBANS scores, controlling age, education, and sleep duration. There were significant main effects of sex on Immediate Memory, Attention, and Total score. Interactions between sleep consistency and sex were significant for Immediate Memory, Delayed Memory, and Total score. Conclusions: Sleep consistency is associated with better cognitive performance across domains. Women perform better than men globally and in domains of immediate memory and attention, regardless of consistency. Women who sleep consistently are most likely to exhibit better memory and global cognitive function. Findings extend sleep duration effects on cognitive function to variability and suggest consistency may benefit women more than men.