Worse sleep architecture but not self-reported insomnia and sleepiness is associated with higher cortisol levels in menopausal women

•Self-reported insomnia and sleepiness are not associated with cortisol levels in menopausal women.•Lower sleep efficiency and fewer REM periods relate to higher cortisol levels.•More wake after sleep onset is associated with higher cortisol levels.•Poorer short-wave sleep is associated with a greater cortisol awakening response.•Deterioration in sleep architecture may interfere with cortisol secretion. Worsening of sleep quality during menopause is well recognized. However, the underlying hormonal regulation is insufficiently described. In this study, we evaluated associations between sleep and cortisol levels. Seventeen perimenopausal and 18 postmenopausal women were enrolled in a three-night sleep study. Diurnal blood sampling was performed during the third night and the following day. Self-reported insomnia and sleepiness were evaluated with the Basic Nordic Sleep Questionnaire and sleep architecture with all-night polysomnography. Diurnal cortisol samples were collected at 20-min intervals. Correlation analyses and generalized linear models adjusted by age, body mass index, vasomotor symptoms and depressive symptoms were conducted. In correlation analyses, self-reported insomnia and sleepiness were not associated with cortisol levels. Lower sleep efficiency, slow-wave sleep and stage 1 percentages, number of slow-wave sleep and of rapid-eye-movement (REM) periods, longer slow-wave sleep latency and higher wake after sleep onset percentage were associated with higher cortisol levels (all p