Development of hypertension in individuals with high normal blood pressure is related with sympathetic drive, arterial stiffness, and exercise blood pressure.

Background: High normal blood pressure (HNBP) is common in adults worldwide and is associated with a greater likelihood of developing hypertension. Thus, identifying those at risk is crucial, in order to intervene early and reduce future cardiovascular risk. This study aims to examine the role of sympathetic nervous system (SNS), aortic stiffness, and blood pressure (BP) response to exercise as predictors for development of hypertension in individuals with HNBP.

Methods: One hundred individuals with HNBP were included in the study. Baseline anthropometric characteristics, BP levels, an electrocardiogram, and an echocardiogram were obtained. In order to evaluate the effect of SNS, aortic stiffness, and exercise response in the transition from the prehypertensive to hypertensive phenotype, we measured the levels of muscle sympathetic nerve activity (MSNA), pulse wave velocity (PWV), and exaggerated BP response (EBPR) to cardiopulmonary exercise, respectively.

Results: At 3 years follow up, 40 patients (40%) developed hypertension. Baseline characteristics were similar between the two groups. Those who developed hypertension had sympathetic overactivation, as indicated by the higher mean values of MSNA (35 ± 4.4 vs 28 ± 3.8 bursts per minute; P = 0.003), increased aortic stiffness, and PWV (8.2 ± 0.7 vs 7.2 ± 0.5 m/s; P < 0.001), as well as an EBPR to exercise (P < 0.001).

Conclusion: Increased values of MSNA, PWV, and EBPR were found to be statistically related with hypertension development in HNBP phenotypes. These markers could be of great clinical use in identifying prehypertensives at high risk for developing hypertension.