To Nap or Not to Nap Excessive Daytime Napping Is Associated With Elevated Evening Cortisol in Nursing Home Residents With Dementia

Background:Alterations in the sleep–wake cycle, including daytime napping, are consistently reported in persons with dementia (PWD). A dysregulation in the hypothalamic–pituitary–adrenal (HPA) axis, indexed by elevated evening cortisol, may offer one explanation for these alterations. Alternatively, excessive daytime sleeping may alter cortisol rhythm and increase intraindividual variability, potentially contributing to increased environmental reactivity and behavioral symptoms. The purpose of this substudy (N = 12) was to examine the association between daytime napping and basal cortisol diurnal rhythm in nursing home residents with dementia.Method:In this within-individual longitudinal design, saliva samples were obtained daily for 5 consecutive days upon waking and 30–45 min, 6 hr, and 12 hr after waking to obtain a cortisol diurnal rhythm. Behavior and sleep–wake state (nap/no nap) were observed and recorded every 20 min for 12 hr per day for 5 days.Results:Participants were categorized as high napper...