Increased Rate Pressure Product is Linked to Sympathovagal Imbalance in Indian Obese Postmenopausal Women
Background and Aim: Postmenopausal women experience changes in cardiovascular (CV) system and autonomic functions. Increased body mass index (BMI) alters the autonomic discharge pattern. Rate pressure product (RPP) is linked to autonomic imbalance. However, the autonomic functions status and its link to RPP in Indian obese postmenopausal women are not yet known. The present study was designed to assess sympathovagal imbalance (SVI) and its link to RPP in Indian obese postmenopausal women. Methods: In 104 postmenopausal women of 40–55 years of age, anthropometric indices such as age, height, body weight, waist‑hip ratio, waist‑height ratio, and CV parameters such as heart rate, systolic, and diastolic blood pressure were recorded. BMI, mean arterial pressure and RPP were calculated. Resting heart rate variability was recorded for 5 min in the supine position. Data were compared between obese (BMI >25) and nonobese (BMI 18.5–24.99) women and the link of low frequency to high frequency (LF‑HF) ratio with RPP was assessed by Pearson’s correlation analysis. Results: RPP was increased, sympathetic drive (low‑frequency component expressed as normalized unit) was increased, vagal drive (high‑frequency component expressed as normalized unit) was decreased, and LF‑HF ratio, the marker of SVI was found to be increased in high BMI postmenopausal women. In addition, LF‑HF ratio was significantly associated with RPP. Conclusion: There was SVI with increased sympathetic and decreased vagal function in high BMI postmenopausal women. RPP, the marker of myocardial work stress was associated with SVI.