Baroreflex Sensitivity and Heart Rate Variability Predict Incident Hypertension and Systolic Blood Pressure Increase in a Multi-Ethnic Cohort: The Helius Study

Objective: Cross-correlation baroreflex sensitivity (xBRS) and heart rate variability (HRV) provide valuable insight into neurocardiovascular control. However, their prospective utility in predicting new-onset hypertension and increases in systolic blood pressure (SBP) over time within the general population has not yet been demonstrated. Design and method: Data was collected from participants of the HEalthy Life In an Urban Setting (HELIUS) study. A non-invasive continuous finger blood pressure (BP) measurement at baseline was used to calculate xBRS, standard deviation of the normal-to-normal interval (SDNN) and the squared root of mean squared successive differences between normal-to-normal intervals (RMSDD). In the normotensive individuals at baseline, we used logistic regression models to calculate the odds ratio (OR) of developing hypertension at follow-up, and in the full cohort we assessed the change in SBP, corrected for the use of antihypertensive medication, between baseline and follow-up using linear regression with tertiles and splines where appropriate. A subgroup analyses was performed in the younger (aged < 50 years) and older (aged > 50 years) part of the cohort. Both the logistic and linear regression models were corrected for demographic and confounding factors. Results: Follow-up data from 4,910 participants were available, mean follow-up time was 6.6 years (SD 1.1 years). A 50% reduction in xBRS was associated with an OR of 1.31 (95% CI 1.09–1.57) for developing hypertension at follow-up, with no significant difference between the younger and older subgroups of the cohort. No significant association between SDNN or RMSDD and new-onset hypertension was found. Splines depicting the relation between delta SBP and xBRS, SDNN and RMSDD are depicted in Figure 1. Compared to the lowest tertile, an xBRS in the highest tertile was associated with a 3.61 mmHg (95%CI 2.50-4.71) higher change in SBP over time, whereas this was 1.11 mmHg (95%CI 0.12-2.09) and 1.76 mmHg (95%CI 0.73-2.79) for SDNN and RMSDD, respectively. Conclusions: In the general population, a lower xBRS is associated with increased odds of developing hypertension, and a steeper increase in SBP over time.