{'fraction_non_alphanumeric': 0.018686868686868686, 'fraction_numerical': 0.0030303030303030303, 'mean_word_length': 5.590682196339435, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Could networking and sharing (open) data in an international collaborative effort unravel the mechanisms of sleep disturbances in middle-aged women?

S leep complaints are one of the most common symptoms related to the menopausal transition, affecting 40% to 60% of women. However, the mechanisms underlying sleep disturbances during this period in a woman_s life are still poorly understood. In this issue of Menopause, Kravitz et al collected up to 27 days of actigraphy data and subjective measures in 314 middle-aged premenopausal, perimenopausal, and postmenopausal women to model night-to-night variations in sleep quality and feeling rested in the morning in relation to nighttime pain severity. They reported that nights with higher self-reported pain severity are associated with longer sleep duration but reduced sleep efficiency and feeling less rested in the morning. They also showed that nights with self-reported vasomotor symptoms are associated with higher motor restlessness, lower sleep efficiency, and feeling less rested in the morning. These data suggest that not only vasomotor symptoms but also pain should be taken into account to alleviate sleep difficulties in middle-aged women. The conclusions of this study are enriched by the large sample size, the significant number of days with actigraphy measures (4 wk), and the use of a mixed-effects modeling approach combining cross-sectional and longitudinal estimates while correcting for several factors. However, as acknowledged by Kravitz et al, vasomotor symptoms and pain severity explained only a little of the variance in actigraphy-measured sleep quality. This original contribution adds to a field of research that needs global effort to fill major gaps in knowledge necessary to significantly reduce sleep difficulties in women during the menopausal transition. There is a need to collectively make use of the enormous quantity of sleep data lying in drawers worldwide and to coordinate further investigations internationally. Thus, this conundrum can best be resolved by an integrated research network approach. Recently, larger population-based studies assessing objective and subjective sleep variables have greatly improved statistical power, control of confounding factors, and sample bias, which limited earlier observations. The study by Kravitz et al constitutes a good example of this effort to evaluate a large number of women using a longitudinal design and valid objective sleep measures. However, results from these larger population studies are still difficult to reconcile together because of diverse methodological designs, differing definitions of Bthe menopausal transition[ and Bvasomotor symptoms[ and absence or variety of hormonal measures, among other things. Heterogeneity between studies prevents robust conclusions about the factors and mechanisms that place middle-aged women at greater risk for sleep disturbances. More than 35 years ago, Erlik et al published their study on the cooccurrence of hot flashes and wake episodes. However, whether vasomotor symptoms are a major contributor to sleep disturbances during the menopausal transition is still being debated (see Regestein for an editorial on this question). Clearly, there is an urgent need for global harmonization and standardization of inclusion/exclusion criteria, objective and subjective sleep variables (eg, questionnaires and sleep measures), methodological approaches, and collection of physiological measures between studies. Predictive models of sleep quality in middle-aged women need to be developed and tested in longitudinal sleep studies of very large community samples. Because of the multivariate nature of research questions and because ecological sleep studies require much expertise and financial resources, international multisite effort is necessary to understand the complex associations between the menopausal transition and subjective and objective sleep in women.