Abstract
BACKGROUND: Sleep is disrupted in depressed subjects, but it also deteriorates with age and possibly with the transition to menopause. The nature of interaction between mood, sleep, age and reproductive state is not well-defined. The aim of this study was to evaluate the relationship between mood and sleep among healthy women in different reproductive states. METHODS: We analyzed data from 11 younger (20-26 years), 21 perimenopausal (43-51 years) and 29 postmenopausal (58-71 years) healthy women who participated in a study on menopause, sleep and cognition. The 21-item Beck Depression Inventory (BDI) was administered to assess mood. Subjective sleep quality was assessed with the Basic Nordic Sleep Questionnaire (BNSQ). Objective sleep was measured with all-night polysomnography (PSG) recordings. Perimenopausal and younger women were examined during the first days of their menstrual cycle at the follicular phase. RESULTS: Among younger women, less arousals associated with higher BDI total scores (p = 0.026), and higher SWS percentages with more dissatisfaction (p = 0.001) and depressive-somatic symptoms (p = 0.025), but with less depressive-emotional symptoms (p = 0.001). In specific, less awakenings either from REM sleep or SWS, respectively, associated with more punishment (p = 0.005; p = 0.036), more dissatisfaction (p < 0.001; p = 0.001) and more depressive-somatic symptoms (p = 0.001; p = 0.009), but with less depressive-emotional symptoms (p = 0.002; p = 0.003). In perimenopausal women, higher BNSQ insomnia scores (p = 0.005), lower sleep efficiencies (p = 0.022) and shorter total sleep times (p = 0.024) associated with higher BDI scores, longer sleep latencies with more depressive-somatic symptoms (p = 0.032) and longer REM latencies with more dissatisfaction (p = 0.017). In postmenopausal women, higher REM percentages associated with higher BDI total scores (p = 0.019) and more depressive-somatic symptoms (p = 0.005), and longer SWS latencies with more depressive-somatic symptoms (p = 0.030). CONCLUSIONS: Depressive symptoms measured with the total BDI scores associated with sleep impairment in both perimenopausal and postmenopausal women. In younger women, specific BDI factors revealed minor associations, suggesting that the type of sleep impairment can vary in relation to different depressive features. Our data indicate that associations between sleep and depressed mood may change in conjunction with hormonal milestones.