Oxygen saturation during sleep as a predictor of inflammation in anovulatory women

Abstract

To evaluate the inflammatory profile of premenopausal women with anovulatory cycles, regular menstrual cycles, or using contraceptives, and the associations with sleep and health-related parameters. Subjects completed questionnaires including the Pittsburgh Sleep Quality Index and the Epworth sleepiness scale, underwent whole-night polysomnography, and had blood collected for analysis of inflammatory, cardiovascular, and hormonal parameters. Women of reproductive age were categorized into three groups for comparisons: anovulatory menstrual cycles, regular menstrual cycles, and hormonal contraceptive use. Women with anovulatory menstrual cycles (n = 20) had higher circulating levels of the proinflammatory cytokine IL-6 compared with women who had regular menstrual cycles (n = 191) and those on hormonal contraception (n = 72). No other classical marker of low-grade inflammation was significantly different. Subjective and objective sleep data were similar among groups. However, the mean peripheral oxygen saturation (SpO2) during sleep was reduced in anovulatory women. The analysis of associated variables of the inflammatory profile demonstrated that mean SpO2 during sleep was a predictive factor of IL-6 levels. Our data suggest that in premenopausal women with anovulation, a proinflammatory condition mediated by IL-6 is associated with lower oxygen levels during sleep. These findings reflect the balance between gynecological status, the immune system, and sleep, pointing to the need to control for these factors in clinical practice and research contexts.