Factors associated with intra-individual visit-to-visit variability of blood pressure in four countries: the INTERMAP study

Variability in home blood pressure and its association with renal function and pulse pressure in patients with treated hypertension in primary care

Blood pressure variability (BPV) represents a cardiovascular risk factor, regardless of mean level of blood pressure (BP). In this post-hoc analysis from the PERson-centredness in Hypertension management using Information Technology (PERHIT) study, we aimed to explore BPV in daily home measurements in hypertensive patients from primary care, to identify factors associated with high BPV and to investigate whether estimated glomerular filtration rate (eGFR) and pulse pressure, as markers of target organ damage (TOD), are associated with BPV. For eight consecutive weeks, 454 participants reported their daily BP and heart rate in their mobile phone, along with reports of lifestyle and hypertension-related factors. Systolic BP (SBP) values were used to calculate BPV with coefficient of variation (CV) as primary estimate. Background characteristics and self-reports were tested between fifths of CV in a linear regression model, adjusted for age and sex. Associations between BPV and eGFR and pulse pressure were tested with linear and logistic regression models. Higher home BPV was associated with higher age, BP, heart rate, and smoking. BPV was lower for participants with low alcohol consumption and treatment with calcium channel blockers. There was a significant association between BPV and pulse pressure (P = 0.015), and between BPV and eGFR (P = 0.049). Participants with high BPV reported more dizziness and palpitations. In conclusion, pulse pressure and eGFR were significantly associated with home BPV. Older age, high BP, heart rate, and smoking were associated with high BPV, but treatment with calcium channel blockers and low alcohol consumption was associated with low BPV. Trial registration: The study was registered with ClinicalTrials.gov [NCT03554382].

Urinary Sodium Excretion and Salt Intake Are Not Associated With Blood Pressure Variability in a White General Population

Background Salt restriction may lower blood pressure variability (BPV), but previous studies have shown inconsistent results. Therefore, we investigated in an observational study and intervention trial whether urinary sodium excretion and salt intake are associated with 24-hour BPV. Methods and Results We used data from the cross-sectional population-based Maastricht Study (n=2652; 60±8 years; 52% men) and from a randomized crossover trial (n=40; 49±11 years; 33% men). In the observational study, we measured 24-hour urinary sodium excretion and 24-hour BPV and performed linear regression adjusted for age, sex, mean blood pressure, lifestyle, and cardiovascular risk factors. In the intervention study, participants adhered to a 7-day low- and high-salt diet (50 and 250 mmol NaCl/24 h) with a washout period of 14 days, 24-hour BPV was measured during each diet. We used linear mixed models adjusted for order of diet, mean blood pressure, and body mass index. In the observational study, 24-hour urinary sodium excretion was not associated with 24-hour systolic or diastolic BPV (β, per 1 g/24 h urinary sodium excretion: 0.05 mm Hg [95% CI, -0.02 to 0.11] and 0.04 mm Hg [95% CI, -0.01 to 0.09], respectively). In the intervention trial, mean difference in 24-hour systolic and diastolic BPV between the low- and high-salt diet was not statistically significantly different (0.62 mm Hg [95% CI, -0.10 to 1.35] and 0.04 mm Hg [95% CI, -0.54 to 0.63], respectively). Conclusions Urinary sodium excretion and salt intake are not independently associated with 24-hour BPV. These findings suggest that salt restriction is not an effective strategy to lower BPV in the White general population. Registration URL: https://clinicaltrials.gov/ct2/show/NCT02068781.

Cardio-ankle vascular index is more closely associated than brachial-ankle pulse wave velocity with arterial damage and risk of cardiovascular disease in patients with diabetes

Background

This study aimed to compare the usefulness of arterial stiffness parameters, cardio-ankle vascular index (CAVI) and brachial-ankle pulse wave velocity (baPWV), for evaluating arterial damage and risk of cardiovascular disease (CVD) in subjects with diabetes.

Methods

The study subjects were 277 patients with type 1 or type 2 diabetes. All subjects were evaluated for vascular stiffness using CAVI (n = 154) or baPWV (n = 123). Carotid intima-media thickness (IMT) and the Suita score were also measured because these are established risk factors for future CVD. Associations of both CAVI and baPWV with these established parameters were evaluated in all subjects, and then in 174 subjects with adjustment for covariates by using propensity score matching.

Results

In all subjects, CAVI and baPWV correlated significantly with both IMT (r = 0.462, P < 0.001, and r = 0.212, P = 0.019, respectively) and the Suita score (r = 0.573, P < 0.001, and r = 0.373, P < 0.001, respectively). The correlation between CAVI and IMT was more significant than that between baPWV and IMT (Z = 2.33, P = 0.020). Similarly, the correlation between CAVI and the Suita score was more significant than that between baPWV and the Suita score (Z = 2.13, P = 0.033). After adjustment by propensity score matching, significant correlations between CAVI and IMT (r = 0.432 P < 0.001) and between CAVI and the Suita score (r = 0.544, P < 0.001) were preserved, though only the association between baPWV and the Suita score was significant (r = 0.289, P = 0.007) while that between baPWV and IMT showed no significance. Again, CAVI showed a significant association with the Suita score than baPWV (Z = 2.02, P = 0.043).

Conclusions

CAVI is more closely associated than baPWV with arterial damage and risk of CVD in patients with diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02800-9.

Visit-to-visit blood pressure variability is common in primary care patients: Retrospective cohort study of 221,803 adults

Objective

Although high visit-to-visit blood pressure variability (BPV) is an independent risk factor for cardiovascular events, the frequency of high BPV is unknown. We conducted this study to define the frequency of high BPV in primary care patients, clinical correlates, and association with antihypertensive therapies.

Methods

Retrospective cohort study using electronic medical record data (with previously validated case definitions based on billing codes, free text analysis of progress notes, and prescribing data) from the Canadian Primary Care Sentinel Surveillance Network of 221,803 adults with multiple clinic visits over a 2-year period. We a priori defined a standard deviation>13.0 mm Hg in visit-to-visit systolic blood pressure (SBP) as “high BPV” based on prior literature.

Results

Overall, 85,455 (38.5%) patients had hypertension (mean 6.56 visits with SBP measurement, mean SBP 134.4 with Standard Deviation [SD] 11.3, 33.2% exhibited high BPV) and 136,348 did not (mean 3.96 visits with SBP measurement, mean SBP 120.9 with SD 8.2, 16.5% had high BPV). BPV increased with age regardless of whether individuals had hypertension or not; at all ages BPV varied across antihypertensive treatment regimens and was greater in those receiving renin angiotensin blockers or beta-blockers (p<0.001). High BPV was more frequent in patients with diabetes, chronic kidney disease, dementia, depression, chronic obstructive pulmonary disease, or Parkinson’s disease.

Conclusions

High visit-to-visit BPV is present in one sixth of non-hypertensive adults and one third of hypertensive individuals and is more common in those with comorbidities. The frequency of high BPV varies across antihypertensive treatment regimens.

Association of 1-Year Blood Pressure Variability With Long-term Mortality Among Adults With Coronary Artery Disease: A Post Hoc Analysis of a Randomized Clinical Trial

Importance

Accumulating evidence indicates that higher blood pressure (BP) variability from one physician office visit to the next (hereafter referred to as visit-to-visit BP variability) is associated with poor outcomes. Short-term measurement (throughout 1 year) of visit-to-visit BP variability in high-risk older patients may help identify patients at increased risk of death.

Objective

To evaluate whether short-term visit-to-visit BP variability is associated with increased long-term mortality risk.

Design, Setting, and Participants

The US cohort of the International Verapamil SR-Trandolapril Study (INVEST), a randomized clinical trial of 16 688 patients aged 50 years or older with hypertension and coronary artery disease, was conducted between September 2, 1997, and December 15, 2000, with in-trial follow-up through February 14, 2003. The study evaluated a calcium antagonist (sustained-release verapamil plus trandolapril) vs β-blocker (atenolol plus hydrochlorothiazide) treatment strategy. Blood pressure measurement visits were scheduled every 6 weeks for the first 6 months and biannually thereafter. Statistical analysis was performed from September 2, 1997, to May 1, 2014.

Exposures

Visit-to-visit systolic BP (SBP) and diastolic BP variability during the first year of enrollment using 4 different BP variability measures: standard deviation, coefficient of variation, average real variability, and variability independent of the mean.

Main Outcomes and Measures

All-cause death, assessed via the US National Death Index, beginning after the exposure assessment period through May 1, 2014.

Results

For the present post hoc analysis, long-term mortality data were available on 16 688 patients (9001 women [54%]; mean [SD] age, 66.5 [9.9] years; 45% White patients, 16% Black patients, and 37% Hispanic patients). During a mean (SD) follow-up of 10.9 (4.2) years, 5058 patients (30%) died. All 4 variability measures for SBP were significantly associated with long-term mortality after adjustment for baseline demographic characteristics and comorbidities. After comparison of lowest vs highest variability measure quintiles, the magnitude of the association with death remained statistically significant even after adjustment for baseline demographic characteristics and comorbidities (average real variability: adjusted hazard ratio [aHR], 1.18; 95% CI, 1.08-1.30; standard deviation: aHR, 1.14; 95% CI, 1.04-1.24; coefficient of variation: aHR, 1.15; 95% CI, 1.06-1.26; variability independent of the mean: aHR, 1.15; 95% CI, 1.05-1.25). The signal was stronger in women compared with men. Associations of diastolic BP variability measures with death were weaker than for SBP and were not significant after adjustment.

Conclusions and Relevance

This study suggests that, in a large population of older patients with hypertension and coronary artery disease, short-term visit-to-visit SBP variability was associated with excess long-term mortality, especially for women. Efforts to identify and minimize visit-to-visit SBP variability may be important in reducing excess mortality later in life.

Trial Registration

ClinicalTrials.gov Identifier: NCT00133692.

Preoperative outpatient blood pressure variability predicts postoperative mortality, readmission and morbidity after surgery

BACKGROUND

Outpatient blood pressure variability (BPV) predicts hospitalization and death in non-surgical patients independently of hypertension. We hypothesized that preoperative BPV predicts postoperative outcomes.

METHODS

We assessed 22,233 veterans undergoing CABG, colectomy, hip replacement, pancreatectomy, carotid endarterectomy or AV-fistula with ≥10 outpatient BP's over three preoperative years. Calculating BPV as SD of systolic or diastolic BP, we used logistic regression considering demographics, comorbidities, and pre-admission cardiovascular medications to estimate odds ratios for 90-day mortality or readmission, MI, CVA, renal failure, and wound infection, choosing the lowest 5%ile of systolic/diastolic BPV for reference.

RESULTS

Covariate-adjusted ORs for adverse outcomes increased as BPV increased. For instance, the highest 5%ile of systolic BPV had covariate-adjusted ORs of 2.96 and 1.78 for 90-day mortality and readmission. Systolic and diastolic BPV trended together but affected outcomes independently.

CONCLUSIONS

Preoperative BPV predicts postoperative outcomes. BPV should be considered in individualized risk assessment and subgroup risk stratification.