Cardiovagal baroreflex sensitivity, blood pressure and blood pressure variability - the Maastricht study

OBJECTIVE: Low baroreflex sensitivity (BRS) has been hypothesized to underlie high blood pressure (BP) and greater BP variability on the longer term, but evidence is scarce. In addition, these associations may differ by sex and (pre)diabetes. Therefore, we investigated whether cardiovagal BRS is associated with short- to mid-term mean BP and BP variability, and differs according to sex and (pre)diabetes.

METHODS: Cross-sectional data from the population-based Maastricht study (age 60 ± 8 years, 52% men), where office (n = 2846), 24-h (n = 2404) and 7-day BP measurements (n = 2006) were performed. Spontaneous BRS was assessed by cross-correlating systolic BP and instantaneous heart rate. We used linear regression with adjustments for age, sex, BP or BP variability, and cardiovascular risk factors.

RESULTS: With regard to BP, 1-SD (standard deviation) lower BRS (-5.75 ms/mmHg) was associated with higher office, 24-h and 7-day systolic BP (2.22 mmHg [95% confidence interval [CI]: 1.59; 2.80], 0.95 mmHg [0.54; 1.36], and 1.48 mmHg [0.99; 1.97], respectively) and diastolic BP (1.31 mmHg [0.97; 1.66], 0.57 mmHg [0.30; 0.84], and 0.86 mmHg [0.54; 1.17], respectively). Per 1-SD lower BRS, these associations were stronger in women (0.5-1.5 mmHg higher compared to men), and weaker in those with type 2 diabetes (1-1.5 mmHg lower compared to normal glucose metabolism). With regard to BP variability, BRS was not consistently associated with lower BP variability.

CONCLUSIONS: Lower cardiovagal BRS is associated with higher mean BP from the short- to mid-term range, and not consistently with BP variability. The associations with mean BP are stronger in women and weaker in those with type 2 diabetes.