Wearable-Measured Heart Rate Variability and Premenstrual Disorder Symptoms across Menstrual Cycle

IMPORTANCEPremenstrual disorders (PMDs), characterized by affective symptoms before menses, significantly impact women who are suffering. Current diagnostic tools are time-consuming and challenging in practice, resulting in delay in detection and treatment. There is an urgent need to identify objective and easily accessible measures to streamline the diagnostic process for PMDs. ObjectivesTo investigate the menstrual fluctuation of wearable device-based real-time heart rate variability (HRV) through menstrual cycles and its associations with premenstrual disorders (PMD) symptoms. Design, Setting, and ParticipantsWe conducted a prospective study of female participants nested from the Care of Premenstrual Emotion Cohort. Exposure outcome and measuresDaily HRV metrics (SDNN, rMSSD, LF, HF, and LF/HF) were estimated from consecutive RR-intervals (RRI) collected by the Huawei Fitness Tracker 6 Pro at 5-minute intervals over 1-2 menstrual cycles and averaged on records during 03:00-05:00 a.m. PMD symptoms were assessed with the Daily Record of Severity of Problems on a daily basis. HRV variability across cycles was described using descriptive statistics and splines, while associations between HRV metrics and PMD symptoms were estimated using a mixed-effect model. ResultsIn total, 193 participants (with 68 prospectively confirmed PMDs) were included, with measures from 293 menstrual cycles. In both women with and without PMDs, SDNN, rMSSD, and HF decreased before menses and increased afterwards; the increase trends were more pronounced in women without PMDs. During the week before or after menses, levels of these HRV metrics were inversely associated with PMD symptoms among women with PMDs (e.g., rMSSD, postmenstrual week, {beta} = -0.036 per SD, 95% CI: -0.048 to -0.065), whereas null association was noted for those without PMDs ({beta} = -0.001, 95% CI -0.011 to 0.009; P-for-difference < 0.001). The association was particularly stronger with affective symptoms than with physiological symptoms, and more pronounced during the premenstrual week among women with premenstrual dysphoric disorder compared with those with premenstrual syndrome. Conclusion and RelevanceOur findings suggest that wearable device-estimated HRV metrics fluctuate across menstrual cycles, with varying strengths of association with PMD symptoms between individuals with and without PMDs, which may aid future diagnostic process for PMDs. Key PointsO_ST_ABSQuestionC_ST_ABSDoes heart rate variability (HRV) vary across menstrual cycle? Is HRV associated with premenstrual disorder symptoms in a different way between women with and without PMDs? FindingsIn a sample of 68 women with PMDs and 125 women without PMDs, temporal patterns across menstrual cycle were found for several wearable-measured HRV metrics in both groups. The associations between HRV and PMD symptoms during one week before or after menses were stronger among women with PMDs compared to those without. MeaningHRV fluctuates across menstrual cycles, with varying strengths of association with PMD symptoms between women with and without PMDs.