Menopausal Symptom Burden and Self-Reported Poor Sleep Quality Among Japanese Working Women Aged 40 Years and Older: An Exploratory Cross-Sectional Study

Background and Objectives: Sleep-related complaints are common among women in midlife and may reflect not only insufficient sleep duration but also broader menopausal symptom burden. Although menopausal symptoms and sleep problems are known to be related, less is known about how menopausal symptom domains are associated with self-reported sleep quality among working women, particularly when objective sleep duration is considered. This exploratory cross-sectional study aimed to examine the association between menopausal symptom burden and self-reported poor sleep quality among Japanese working women aged 40 years and older, while accounting for objectively measured sleep duration. Materials and Methods: Participants completed questionnaires on sleep quality and menopausal symptoms and underwent objective sleep monitoring using a wearable electroencephalography device. Self-reported sleep quality was assessed using an item corresponding to the Pittsburgh Sleep Quality Index and dichotomized into poor and good sleep quality. Menopausal symptoms were evaluated using the Simplified Menopausal Index, including vasomotor, psychological, and somatic domains, with higher scores indicating greater symptom burden. Results: Among 79 participants, 43 reported poor sleep quality and 36 reported good sleep quality. Women with poor sleep quality had higher total and domain-specific SMI scores and shorter objective sleep duration. In logistic regression analyses adjusted for age and objective sleep duration, total SMI score and each symptom domain were associated with poor sleep quality. These associations remained significant in sensitivity analyses excluding the sleep-related SMI item from the total score and psychological domain score. Conclusions: Self-reported poor sleep quality among Japanese working women aged 40 years and older may reflect menopausal symptom burden beyond objectively measured sleep duration. The consistency of the findings across sensitivity analyses supports the robustness of this association. Sleep complaints may therefore serve as an accessible signal for recognizing menopausal symptom burden in clinical and occupational health settings.