An Analytical Study of Heart Rate Variability in Newly Diagnosed Hypertensive Patients and Normotensive Subjects

Abstract

Background: An adequate blood pressure is necessary for proper organ perfusion. Hypertension is a complex and non-communicable medical condition with increased blood pressure. The autonomic nervous system (ANS) regulates the cardiovascular system, and sympathetic overactivity contributes not only to the initiation of essential hypertension but also to its progression and associated complications. Heart rate variability (HRV) is regarded as a non-invasive, sensitive measure of autonomic function, particularly useful for assessing sympathovagal balance. In this study, the changes in heart rate variability in patients of essential hypertension and age & sex matched healthy normotensive subjects were assessed. This study hypothesized that frequency domain parameters of heart rate variability may vary between patients with essential hypertension and in healthy normotensive subject. Material and methods: The present study was conducted on total 200 participants – 100 newly diagnosed essential hypertensive and 100 age & sex matched healthy normotensive subjects. Data collection was started after obtaining prior ethical approval from the institutional ethics committee. Anthropometric parameters were recorded. HRV data was obtained using beat-to-beat human NIBP (non – invasive blood pressure) machine. Mean ± SD were used to expressed quantitative variables. Outcome Variables were analysed using parametric and non-parametric tests. Statistical significance was assigned at p-value<0.05. Results: The anthropometric parameters of essential hypertensive patients’ group and normotensive subjects’ group age, height did not show any statistically significant difference between the two groups. Weight and BMI were significantly higher in hypertensive patients as compared to healthy normotensive subjects. The mean ± SD difference of resting heart rate and resting blood pressure among hypertensive patients and normotensive subjects statistically significant. The mean ± SD difference of HRV parameters among hypertensive patients and normotensive subjects statistically significant. Conclusion: This study concluded that hypertensive patients have sympathovagal imbalance with increased sympathetic activity and decreased parasympathetic as compared to normotensive subjects.