Abstract

Background: Heart rate variability (HRV) has been proposed as the most sensitive indicator of autonomic function especially for the assessment of sympathovagal balance. It has also been proposed that there is sympathetic hyperactivity in postmenopausal women and parasympathetic dominance in women of reproductive age group due to the effect of estrogen. Objectives: The aim of the study was to compare the basal cardiovascular parameters and HRV between premenopausal and postmenopausal women.
Materials and Methods: This was a cross-sectional observational study carried out in Sri Venkateshwaraa Medical College Hospital and Research Centre, Puducherry. After 15 min of rest, ECG was recorded among 38 premenopausal and 37 postmenopausal women in the supine position for 5 min using PHYSIOPAC-PP (Medicaid Systems Chandigarh). 4 The frequency domain parameters of HRV were analyzed using a Kubios analyzer. The data were presented as mean(SD). Student’s unpaired t-test was used to find the statistical difference between the two groups. p-Value < 0.05 was considered statistically significant.
Results: Systolic blood pressure (p = 0.022), pulse pressure (p = 0.033), and rate pressure product (p = 0.003) values were significantly higher in postmenopausal women compared to premenopausal women. Total power ( p = 0.003), an index of parasympathetic activity, was significantly higher among premenopausal women. LF (nu), HF (nu), and LF/HF ratio were similar among both the groups. Conclusion: Though LF (nu), HF(nu), and LF/HF ratio between the two groups remain unchanged, the total power shows increased parasympathetic activity in premenopausal women. This effect could be attributed to the effect of estrogen, which is higher among premenopausal women compared to postmenopausal women.