Association between B-type natriuretic peptide and within-visit blood pressure variability

Combined effect of visit-to-visit variations in heart rate and systolic blood pressure on all-cause mortality in hypertensive patients

Elevated resting heart rate (RHR) and systolic blood pressure (SBP) are independent risk factors for all-cause mortality in hypertensive patients. However, the association of the visit-to-visit variation (VVV) in SBP and RHR with the risk of mortality in hypertensive patients remains unknown. The aim of this study was to investigate the effects of the VVVs in SBP and RHR on the risk of all-cause mortality. We enrolled 16,602 hypertensive patients from the Kailuan cohort study who underwent three health examinations from 2006 to 2010. The VVVs in SBP and RHR were defined by the coefficient of variation, standard deviation, variability independent of the mean, and average real variability. High variability was defined as the highest quartile of variability. Participants were classified numerically according to the number of high-variability parameters (e.g., a score of 2 indicated high variability in two parameters). Cox proportional hazards models were used to estimate hazard ratios for mortality. High VVVs in SBP and RHR were associated with an increased risk of all-cause mortality in hypertensive patients. In the multivariable-adjusted model comparing a score of 0 with a score of 2, the hazard ratios (95% confidence intervals (CIs)) for all-cause mortality were 1.38 (1.11-1.69), 1.52 (1.24-1.87), 1.32 (1.07-1.63), and 1.43 (1.16-1.75) using the coefficient of variation, standard deviation, variability independent of the mean, and average real variability, respectively. High VVVs in SBP and RHR constituted an independent risk factor for all-cause mortality in hypertensive patients. High VVVs in SBP and RHR additively increased the risk of all-cause mortality in hypertensive patients.

Blood Pressure Variability and Atrial Fibrillation in Patients with Acute ST Segment Elevation Myocardial Infarction: The Relation with Left Atrial Electromechanical Delay - A 1-Year Follow-Up Study

Purpose

To investigate the association between 24-h blood pressure variability (BPV) and atrial electromechanical delay (EMD) in patients with ST segment elevation myocardial infarction (STEMI) who developed new-onset atrial fibrillation (NOAF).

Materials and Methods

A total of 175 STEMI patients (age 56.6 ± 10.5 years) who underwent primary percutaneous coronary intervention were subjected to in-hospital 24-h ambulatory BP monitoring, comprehensive echocardiography, and assessment of atrial EMD. The parameters of BPV analyzed were: (a) 24-h standard deviation (SD), (b) the coefficient of variation, and (c) the average of the daytime and nighttime SDs weighted for the duration of the daytime and nighttime interval (SD_dn ).

Results

Based on the median of BPV index (SD_dn) = 9.5 mm Hg of all participants, patients were stratified into low and high variability groups (SD_dn: 7.1 ± 1.5 vs.13.5 ± 2.9; p < 0.001). Of the 175 patients with STEMI, 29 (16.7%) patients developed NOAF; 26 (28.9%) were in the high variability group and 3.5% were in the low variability group (p < 0.001). Echocardiographic data showed that the left atrial volume index (p < 0.01) and E/e' ratio (p < 0.001) were significantly higher in patients with high BPV. Inter and intra-atrial EMD were significantly increased in the high variability group compared to the low variability group (p < 0.001). With multiple linear analysis, there was significant correlation between SD_dn and intra-left atrial and inter-atrial EMD (p < 0.001 and <0.01, respectively). Cox regression analysis revealed that SD_dn and intra-atrial EMD were independent predictors for NOAF in patients with STEMI (OR = 3.75 and 02.72, respectively; p < 0.001). ROC analysis revealed that SD_dn ≥12.8 was the optimal cut-off value for predicting NOAF during follow-up.

Conclusions

Short-term BPV was associated with NOAF during the 1-year follow-up in patients with STEMI. In addition, BPV was correlated significantly with atrial EMD. Herein, BPV was predicted to be an early predictor of NOAF in patients with STEMI.

Association between B-type natriuretic peptide and within-visit blood pressure variability

BACKGROUND

Blood pressure variability (BPV) has been shown to predict cardiovascular events. Within-visit BPV is the simplest and easiest measure of BPV, but previous studies have shown conflicts as to whether within-visit BPV correlates with target organ damage. We aimed to evaluate whether within-visit BPV correlates with B-type natriuretic peptide (BNP) in a general population.

HYPOTHESIS

Within-visit BPV correlates with BNP in a general population.

METHODS

This was a cross-sectional study that included 633 individuals, randomly selected, age 45 to 99 years, registered in the primary care program from an urban medium-sized town. Patients were scheduled for a single-day visit that consisted of clinical evaluation and laboratory tests. Three blood pressure (BP) readings, 1 minute apart, were done, and within-visit BPV was determined as the coefficient of variation (CV) of the 3 BP measures. Our main outcome was to correlate BNP and within-visit BPV. A multivariable model was estimated using a generalized linear model to evaluate the independent effects of different variables on BNP levels.

RESULTS

The median age was 57 years. Median BNP was 16 pg/mL, and the median systolic and diastolic BP-CV were, respectively, 3.9% and 3.5%. There was a weak but positive correlation between BNP and both systolic BP-CV and diastolic BP-CV (r = 0.107 and P = 0.007 and r = 0.092 and P = 0.019, respectively). In multiple regression equation, systolic BP, diastolic BP-CV, body mass index, and estimated glomerular filtration rate were associated with BNP.

CONCLUSIONS

In the present study, there was a positive, albeit weak, correlation between within-visit BPV and BNP. In addition, diastolic BPV was associated with BNP even after adjustment for multiple confounders.