0274 Differential Cognitive Impairments in Experimental Chronic Partial Sleep Restriction Between Men and Women

Chronic partial sleep restriction is endemic in the general population, and few previous studies have analyzed detailed neurocognitive functional domains over a longitudinal time course of sleep restriction. We aimed to assess cognitive functioning in individuals undergoing an inpatient experimental paradigm of prolonged sleep restriction vs. control sleep. Seventeen subjects underwent sleep restriction and a control sleep sequence in random order. The sleep restriction sequence consisted of 3 nights of acclimation (9 hours of time in bed), then a 9 night experimental phase of restricted sleep (4 hours of time in bed), followed by a 3 night recovery period of unrestricted sleep. In each phase, subjects underwent repeated sessions of neurocognitive testing (NCT) with CNS Vital Signs to determine cognitive performance. Mixed-effects regression was used to test for significant differences between sleep restriction and control sleep conditions, and explore possible differences between the sexes. Overall neurocognitive index composite score, and domain scores for cognitive flexibility and executive function were significantly lower during the restricted sequence than during the control sequence following 8 nights of sleep restriction (all p < 0.005). Men had significantly lower psychomotor and processing speed domain scores than women following 2 nights of sleep restriction (both p < 0.04). Additionally, sleep restricted men had significantly lower reaction time domain scores than women following 5 nights of sleep restriction (p = 0.035). No significant sex specific neurocognitive score differences were found during the recovery phase. Partial chronic sleep restriction impairs cognitive performance, especially in men. Our findings provide further evidence demonstrating the cumulative deleterious impact of chronic partial sleep loss on cognitive functioning, and may inform patient counseling and public health initiatives to assure sufficient sleep. NIH/NHLBI R01 HL 114676