Autonomic Nervous System Derangement as a Predictor of Cardiovascular Disease in Obese Postmenopausal Women

Background and Aim Cardiovascular disease is more prevalent in women after menopause and particularly in those aged > 60 years. Obesity during menopause has become a growing cause of concern as the source of estrogen during this period is extragonadal. Autonomic function tests serve as effective markers of autonomic activity. Any derangement of autonomic functions in obese postmenopausal women would serve as an early marker for the detection of cardiovascular disease. The aims and objectives of this study were to measure autonomic functions tests in obese postmenopausal women and to correlate the autonomic activity with anthropometric parameters and serum estrogen levels. Material and Methods A cross-sectional study of 101 postmenopausal women aged > 45 years was undertaken. Women with heart disease, diabetes mellitus, hypertension, and respiratory disorders were excluded from this study. A digital data acquisition system, Lab Chart Pro 8.0 was used to perform the autonomic function tests. Results Parasympathetic activity decreased significantly with higher body mass index (BMI). Sympathetic activity that includes diastolic blood pressure and blood pressure measured after isometric handgrip test significantly increased with BMI. A strong negative correlation existed between BMI and parasympathetic high-frequency (HF) domain index. There was a strong positive correlation between BMI and serum estradiol levels. Conclusion Measuring the autonomic activity in obese postmenopausal women along with anthropometric indices and estrogen levels would provide strong evidence of a potential target for existing as well as future heart disease. Any autonomic dysfunction, if detected early, would enable early interventions to prevent heart disease.