The Relationship between Menopausal Symptoms and Heart Rate Variability in Middle Aged Women

BACKGROUND The study of the correlation of menopausal symptoms with heart rate variability (HRV) has not been adequate. The aim of this study was to investigate the relationship between postmenopausal symptoms measured by the menopause rating scale (MRS) and HRV. METHODS We assessed postmenopausal symptoms (using MRS) with age, BMI, educational status, occupation, marital status, alcohol and caffeine consumption, smoking history, exercise, duration of sleep and amenorrhea, degree of anxiety and depression, menarcheal age, and heart rate variability. For evaluation of HRV, the record of electrocardiogram for 5 minutes in the resting state was divided into temporal categories and frequency categories, and analyzed. RESULTS No significant differences in age, BMI, duration of amenorrhea, heart rate, systolic blood pressure, diastolic blood pressure, fasting blood sugar, triglyceride, and high-density lipoprotein were observed between two groups, which were divided according to menopausal symptoms. Low frequency/high frequency (LF/HF) ratio was significantly higher in symptomatic women, compared with asymptomatic women (P < 0.05). No significant differences of HRV index by the severity of postmenopausal symptoms were observed. LF/HF ratio of HRV parameters showed a significant increase in moderate or severe degree of "hot flashes" and "sleep problem" score (P < 0.05). Anxiety scale in symptomatic women was significantly higher than in asymptomatic women (P < 0.05). CONCLUSION The above data suggest that postmenopausal symptoms are associated with altered autonomic control of heart rate. In particular, hot flashes and sleep problems in moderate or severe degree are related to increase of sympathetic nerve activity.