Sympathovagal imbalance in prehypertension status

Heart rate variability (HRV) had been promoted for longer than half a century to monitor the activity of autonomic nerve systems. Previous studies have not clarified the relationship between HRV and prehypertension (pre-HTN) status compared with the normal group. We aimed to figure out the optimal model or cutoff point for predicting the possible pre-HTN status. Patients and Methods: We retrospectively collected and reviewed 2586 Asian people who had joined annual physical examination in Tri-Service General Hospital at 2013. The patient profiles such as age, gender, body height, body weight, body weight index, waist circumferences, and serological biochemistry data were analyzed and correlated with HRV parameter. Results: A total number of 909 patients were enrolled in our study. The physical stress index (PSI) owed a small but most significant Spearman’s relation coefficient (r = 0.118, P < 0.001) among the other HRV parameters. Statistical significant parameters exist between the normal blood pressure group and pre-HTN group other than gender factor. The measured blood pressure increased with elevated PSI level. A PSI level ≥58.4 has a significant β coefficient in each linear regression model for systolic blood pressure and diastolic blood pressure with a P < 0.001 for trend. Conclusion: The PSI level gains a positive correlation to elevated blood pressure. Our study emphasized that PSI is an efficient HRV parameter which represents higher risks for pre-HTN status and elevated blood pressure while the PSI level is >58.4. Early intervention to these participants may decrease cardiovascular events in the coming future.