Visit-to-visit blood pressure variability in the European Lacidipine Study on Atherosclerosis: methodological aspects and effects of antihypertensive treatment

Impact of seasonal blood pressure changes on visit-to-visit blood pressure variability and related cardiovascular outcomes

BACKGROUND

Visit-to-visit blood pressure (BP) variability associates with an increased risk of cardiovascular events. We investigated the role of seasonal BP modifications on the magnitude of BP variability and its impact on cardiovascular risk.

METHODS

In 25 390 patients included in the ONTARGET and TRANSCEND trials, the on-treatment systolic (S) BP values obtained by five visits during the first two years of the trials were grouped according to the month in which they were obtained. SBP differences between winter and summer months were calculated for BP variability quintiles (Qs), as quantified by the coefficient of variation (CV) of on-treatment mean SBP from the five visits. The relationship of BP variability with the risk of cardiovascular events and mortality was assessed by the Cox regression model.

RESULTS

SBP was approximately 4 mmHg lower in summer than in winter regardless of confounders. Winter/summer SBP differences contributed significantly to each SBP-CV quintile. Increase of SBP-CV from Q1 to Q5 was associated with a progressive increase in the adjusted hazard ratio (HR) of the primary endpoint of the trials, i.e. morbid and fatal cardiovascular events. This association was even stronger after removal of the effect of seasonality from the calculation of SBP-CV. A similar trend was observed for secondary endpoints.

CONCLUSIONS

Winter/summer SBP differences significantly contribute to visit-to-visit BP variability. However, this contribution does not participate in the adverse prognostic significance of visit-to-visit BP variations, which seems to be more evident after removal of the BP effects of seasonality from visit-to-visit BP variations.

Effect of Alcohol-Mediated Renal Denervation on Blood Pressure in the Presence of Antihypertensive Medications: Primary Results From the TARGET BP I Randomized Clinical Trial

BACKGROUND

Renal denervation (RDN) has demonstrated clinically relevant reductions in blood pressure (BP) among individuals with uncontrolled hypertension despite lifestyle intervention and medications. The safety and effectiveness of alcohol-mediated RDN have not been formally studied in this indication.

METHODS

TARGET BP I is a prospective, international, sham-controlled, randomized, patient- and assessor-blinded trial investigating the safety and efficacy of alcohol-mediated RDN. Patients with office systolic BP (SBP) ≥150 and ≤180 mm Hg, office diastolic BP ≥90 mm Hg, and mean 24-hour ambulatory SBP ≥135 and ≤170 mm Hg despite prescription of 2 to 5 antihypertensive medications were enrolled. The primary end point was the baseline-adjusted change in mean 24-hour ambulatory SBP 3 months after the procedure. Secondary end points included mean between-group differences in office and ambulatory BP at additional time points.

RESULTS

Among 301 patients randomized 1:1 to RDN or sham control, RDN was associated with a significant reduction in 24-hour ambulatory SBP at 3 months (mean±SD, -10.0±14.2 mm Hg versus -6.8±12.1 mm Hg; treatment difference, -3.2 mm Hg [95% CI, -6.3 to 0.0]; P=0.0487). Subgroup analysis of the primary end point revealed no significant interaction across predefined subgroups. At 3 months, the mean change in office SBP was -12.7±18.3 and -9.7±17.3 mm Hg (difference, -3.0 [95% CI, -7.0 to 1.0]; P=0.173) for RDN and sham, respectively. No significant differences in ambulatory or office diastolic BP were observed. Adverse safety events through 6 months were uncommon, with one instance of accessory renal artery dissection in the RDN group (0.7%). No significant between-group differences in medication changes or patient adherence were identified.

CONCLUSIONS

Alcohol-mediated RDN was associated with a modest but statistically significant reduction in 24-hour ambulatory SBP compared with sham control. No significant differences between groups in office BP or 6-month major adverse events were observed.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02910414.

Comparison between visit-to-visit office and 24-h blood pressure variability in treated hypertensive patients

OBJECTIVES

In any treated hypertensive patient office blood pressure (BP) values may differ between visits and this variability (V) has an adverse prognostic impact. However, little information is available on visit-to-visit 24-h BPV.

METHODS

In 1114 hypertensives of the ELSA and PHYLLIS trials we compared visit-to-visit office and 24-h mean BPV by coefficient of variation (CV) of the mean systolic (S) and diastolic (D) BP obtained from yearly measurements during a 3-4 year treatment period. Visit-to-visit BPV during daytime and night-time were also compared.

RESULTS

Twenty-four-hour SBP-CV was about 20% less than office SBP-CV ( P  < 0.0001). SBP-CV was considerably greater for the night-time than for the daytime period (20%, P  < 0.0001). Results were similar for DBP and in males and females, older and younger patients, patients under different antihypertensive drugs or with different baseline or achieved BP values. In the group as a whole and in subgroups there was significant correlations between office and 24-h BP-CV but the correlation coefficients was weak, indicating that office SBP or DBP CV accounted for only about 1-4% of 24-h SBP or DBP-CV values.

CONCLUSION

Twenty-four-hour mean BP across visits is more stable than across visit office BP. Visit-to-visit office and 24-h BPV are significantly related to each other, but correlation coefficients are low, making visit-to-visit office BP variations poorly predictive of the concomitant 24-h BP variations and thus of on-treatment ambulatory BP stability.

Blood pressure variability: methodological aspects, clinical relevance and practical indications for management - a European Society of Hypertension position paper ∗

Blood pressure is not a static parameter, but rather undergoes continuous fluctuations over time, as a result of the interaction between environmental and behavioural factors on one side and intrinsic cardiovascular regulatory mechanisms on the other side. Increased blood pressure variability (BPV) may indicate an impaired cardiovascular regulation and may represent a cardiovascular risk factor itself, having been associated with increased all-cause and cardiovascular mortality, stroke, coronary artery disease, heart failure, end-stage renal disease, and dementia incidence. Nonetheless, BPV was considered only a research issue in previous hypertension management guidelines, because the available evidence on its clinical relevance presents several gaps and is based on heterogeneous studies with limited standardization of methods for BPV assessment. The aim of this position paper, with contributions from members of the European Society of Hypertension Working Group on Blood Pressure Monitoring and Cardiovascular Variability and from a number of international experts, is to summarize the available evidence in the field of BPV assessment methodology and clinical applications and to provide practical indications on how to measure and interpret BPV in research and clinical settings based on currently available data. Pending issues and clinical and methodological recommendations supported by available evidence are also reported. The information provided by this paper should contribute to a better standardization of future studies on BPV, but should also provide clinicians with some indications on how BPV can be managed based on currently available data.

Beta-blockers in hypertension: overview and meta-analysis of randomized outcome trials

BACKGROUND

Meta-analyses from randomized outcome-based trials have challenged the role of beta-blockers for the treatment of hypertension. However, because they often include trials on diseases other than hypertension, the role of these drugs in the choice of the blood pressure (BP)-lowering treatment strategies remains unclear.

METHODS

Electronic databases were searched for randomized trials that compared beta-blockers vs. placebo/no-treatment/less-intense treatment (BP-lowering trials) or beta-blockers vs. other antihypertensive agents in patients with or without hypertension (comparison trials). Among BP-lowering trials and according to baseline comorbidity, we separately considered trials in hypertension, trials without chronic heart failure or acute myocardial infarction, and trials with either chronic heart failure or acute myocardial infarction. Seven fatal and nonfatal outcomes were calculated (random-effects model) for BP-lowering or comparison trials.

RESULTS

A total of 84 BP-lowering or comparison trials (165 850 patients) were eligible. In 67 BP-lowering trials (68 478 patients; mean follow-up 2.5 years; baseline SBP/DBP, 136/82 mmHg), beta blockers were associated with a lower incidence of major cardiovascular events [risk ratio 0.85 and 95% confidence interval (95% CI) 0.78-0.92] and all-cause death (risk ratio 0.81 and 95% CI 0.75-0.86). Restriction of the analysis to five trials recruiting exclusively hypertensive patients (18 724 patients; mean follow-up 5.1 years; baseline SBP/DBP 163/94 mmHg), a -10.5/-7.0 mmHg BP decrease was accompanied by reduction of major cardiovascular events by 22% (95% CI, 6-34). In 24 comparison trials (103 764 patients, 3.92 years of mean follow-up), beta-blockers compared with other agents were less protective for stroke and all-cause death in all trials and in trials conducted exclusively in hypertensive patients (averaged risk ratio increase 20 and 6%, respectively, for both cases).

CONCLUSION

Compared with other antihypertensive agents, beta-blockers appear to be substantially less protective against stroke and overall mortality. However, they exhibit a substantial risk-reducing ability for all events when prescribed to lower BP in patients with modest or more clear BP elevations, and therefore can be used as additional agents in hypertensive patients.

Impact of in-hospital blood pressure variability on clinical outcomes in patients with symptomatic peripheral arterial disease

Various types of blood pressure (BP) variability have been recognized as risk factors for future cardiovascular events. However, the prognostic impact of in-hospital BP variability in patients with symptomatic peripheral arterial disease (PAD) has not yet been thoroughly investigated. A total of 386 patients with PAD who underwent endovascular therapy in two hospitals were retrospectively included. BP variability was assessed by the coefficient of variation (CV) of systolic BP measured during hospitalization by trained nurses. The primary endpoint was a composite of major adverse cardiovascular events (cardiovascular death, acute coronary syndrome, stroke, and hospitalization for heart failure) and major adverse limb events (major amputation, acute limb ischemia, and surgical limb revascularization). The mean systolic BP and the CV of systolic BP during hospitalization were 130.8 ± 15.7 mmHg and 11.2 ± 4.1%, respectively. During the median follow-up period of 22 months, 80 patients (21%) reached the primary endpoint. Receiver operating characteristic curve analysis showed that the CV of systolic BP significantly predicted major adverse cardiovascular and limb events (area under the curve 0.60, best cutoff value 9.8, P = 0.01). Using the best cutoff value, patients with high BP variability (n = 242) had a higher risk of clinical events than those with low BP variability (n = 144) (26% vs. 12%, P < 0.001). Multivariable analysis indicated that the CV of systolic BP, age, hemodialysis, and atrial fibrillation were associated with the primary endpoint. In conclusion, greater in-hospital systolic BP variability was associated with major adverse cardiovascular and limb events in patients with symptomatic PAD undergoing endovascular therapy.

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.

Association of visit-to-visit variability of systolic blood pressure with cardiovascular disease, chronic kidney disease and mortality in patients with hypertension

OBJECTIVE

This study aimed to evaluate the association between visit-to-visit variability of systolic blood pressure (SBP) and cardiovascular disease, chronic kidney disease, and mortality among hypertensive patients.

METHODS

A population-based cohort included 225 759 Chinese hypertensive adults without diabetes, cardiovascular disease, and chronic kidney disease during 2011-2012. SBP variability was determined based on standard deviations of SBP over the previous 5 years before baseline. Cox regressions adjusted with patients' baseline characteristics, mean, and temporal trend of SBP was applied to the associations between variability and incident cardiovascular disease, chronic kidney disease and all-cause mortality.

RESULTS

In all, 25 714 patients with cardiovascular disease, 27 603 with chronic kidney disease, and 16 778 deaths have occurred during the median follow-up of 70.5 months (1.2 million person-years). SBP variability was continuously and positively associated with higher cardiovascular disease, chronic kidney disease and mortality risk among hypertensive patients without evidence of a threshold. Each 10-mmHg increase in SD of SBP was associated with 35% [hazard ratio 1.35, 95% confidence interval (CI) 1.30-1.39], 39% (HR 1.39, 95% CI 1.35-1.43), and 40% (HR 1.40, 95% CI 1.34-1.45) higher risk of cardiovascular disease, chronic kidney disease and mortality, respectively. HRs were attenuated with increased age, mean SBP, and Charlson index, and decreased temporal trend of systolic blood pressure, but it remained significant and consistent in most of the different subgroups.

CONCLUSIONS

Findings suggested that SBP variability is a significant prognostic value, in addition to baseline or mean of SBP for the risk of cardiovascular disease and mortality.

In-Hospital Blood Pressure Variability: A Novel Prognostic Marker of Renal Function Decline and Cardiovascular Events in Patients with Coronary Artery Disease

INTRODUCTION

Several measures of blood pressure (BP) variability have been associated with kidney disease and cardiovascular events. Although BP is routinely measured during hospitalization in daily practice, the prognostic impact of in-hospital BP and its variability are uncertain.

METHODS

A total of 226 participants who underwent elective percutaneous coronary intervention (PCI) for stable coronary artery disease (CAD) were included. BP was measured by trained nurses during the 4-day hospitalization for PCI. BP variability was assessed by standard deviation (SD) and coefficient variation of systolic BP. Estimated glomerular filtration rate (eGFR) was calculated at baseline and follow-up (≥6 months). The cardiovascular end point was defined as a composite of cardiovascular death, acute coronary syndrome, stroke, heart failure hospitalization, and any coronary revascularization.

RESULTS

In-hospital BP was measured 9.5 ± 0.8 times. During a median follow-up period of 1.7 years, mean eGFR change was -1.7 mL/min/1.73 m2 per year, and 35 (15.5%) participants met the cardiovascular end point. Mean systolic BP and SD were negatively correlated with eGFR change. In the receiver operating characteristic curve analysis, SD of systolic BP predicted the cardiovascular end point (AUC 0.63, best cutoff value 14.2 mm Hg, p = 0.003). Kaplan-Meier analysis demonstrated a significantly higher incidence of the cardiovascular end point in patients with SD of systolic BP ≥14.2 mm Hg compared to their counterpart (p = 0.003). A multivariable analysis showed SD of systolic BP as an independent predictor for the cardiovascular end point. When assessed with coefficient variation, BP variability was similarly related to eGFR change and clinical outcomes.

CONCLUSION

Greater in-hospital BP variability was associated with renal function decline and cardiovascular events in patients with stable CAD.

Impact of visit-to-visit variability in blood pressure on coronary plaque as assessed by integrated backscatter intravascular ultrasound

INTRODUCTION

Visit-to-visit variability (VVV) in blood pressure (BP) has been reported to be a strong predictor of cardiovascular disease. However, the association between VVV in BP and coronary plaque composition has not been fully elucidated.

METHODS

One hundred-two consecutive patients with coronary artery disease (CAD) who underwent percutaneous coronary intervention (PCI) using integrated backscatter (IB) intravascular ultrasound (IVUS), and who had at least six clinic visits a year before PCI were included. We measured systolic and diastolic BP (SBP and DBP) at each visit and determined VVV in BP expressed as the standard deviation of the average BP. Grayscale and IB IVUS examinations were performed for the culprit lesion of a coronary artery just before PCI.

RESULTS

There were no significant associations between the average SBP or DBP and various IVUS parameters. However, VVV in SBP was positively correlated with both the percentage (%) of atheroma volume (β = 0.23, p = .02) and % lipid volume (β = 0.53, p < .0001). VVV in DBP was positively correlated with % lipid volume (β = 0.24, p = .01), while there was no significant correlation between VVV in DBP and % atheroma volume. A  multivariable linear regression analysis showed that VVV in SBP was independently associated with % atheroma volume (p = .04) and % lipid volume (p < .001).

CONCLUSIONS

Larger VVV in SBP was significantly associated with an increased plaque burden and lipid composition at the culprit lesion of a coronary artery in CAD patients. The improvement of VVV in SBP may contribute to the regression and stabilization of coronary plaques.

Visit-to-visit blood pressure variability and renal outcomes: results from ONTARGET and TRANSCEND trials

AIMS

There is conflicting evidence on whether in treated hypertensive patients the risk of renal outcomes is associated with visit-to-visit SBP variability. Furthermore, limited evidence is available on how important is SBP variability for prediction of renal outcomes compared with on-treatment mean SBP. We addressed these issues in 28 790 participants of the Ongoing Treatment Alone and in combination with Ramipril Global End point Trial and Telmisartan Randomized AssessmeNt Study in ACE iNtolerant Subjects with Cardiovascular Disease trials.

METHODS AND RESULTS

SBP variability was expressed as the coefficient of variation of the mean with which it showed no relationship. SBP variability and mean values were obtained from five visits during the first 2 years of treatment after the end of the titration phase. Incidence of several renal outcomes (end-stage renal disease, doubling of serum creatinine, new microalbuminuria, new macroalbuminuria and their composite) was calculated from the third year of treatment onward. Patients were divided in quintiles of SBP-coefficient of variation (SBP-CV) or mean SBP, which exhibited superimposable mean blood pressure and SBP-CV values, respectively. A progressive increase of SBP-CV was not accompanied by a parallel increase in a widely adjusted (baseline and on-treatment confounders) risk of most renal outcomes (end-stage renal disease, new macroalbuminuria, new microalbuminuria and their composite) in the subsequent on-treatment years. In contrast, the adjusted risk of most renal outcomes increased progressively from the lowest to the highest quintile of on-treatment mean SBP. Progression from lowest to highest mean on-treatment SBP, but not SBP-CV, was also associated with a less frequent return to normoalbuminuria in patients with initial micro or macroalbuminuria. Renal outcome prediction was slightly improved by the combined use of SBP-CV and mean SBP quintiles.

CONCLUSION

Visit-to-visit SBP variability had no major predictive value for the risk of renal outcomes, which, in contrast, was sensitively predicted by mean on-treatment SBP. A further slight increase in prediction of renal outcomes was seen by combining on-treatment mean SBP and variability.

Confounding Factors in Renal Denervation Trials: Revisiting Old and Identifying New Challenges in Trial Design of Device Therapies for Hypertension

Recent randomized sham-controlled trials have demonstrated significant blood pressure reductions following renal denervation (RDN) in patients with hypertension, both in the presence and absence of antihypertensive therapy. These new data encouraged us to revisit previously published insights into potential clinical trial confounding factors that informed the design and conduct of forthcoming trials. Initially identified confounders related to procedural technique, medication variability, and selected patient subgroups have been addressed in contemporary trial design. Regarding procedural method and technology, blood pressure reductions may be improved by ensuring circumferential lesion creation in the distal renal arteries and branch vessels. Safety of the RDN procedure has been demonstrated in multiple independent meta-analyses including thousands of treated patients with low reported rates of renal vessel complications and maintenance of renal function. However, a newer generation of RDN trials has also introduced insights related to medication adherence, patient selection, and the definition of treatment response. Evolving evidence indicates that RDN therapy may be considered in higher risk populations of uncontrolled hypertension regardless of ethnicity and in patients expressing a strong preference for a nondrug therapy option. Despite advances in procedural technique and clinical trial conduct, inconsistent antihypertensive-drug adherence behavior remains perhaps the most critical clinical trial design issue for device-based hypertension therapies. As the balance in clinical equipoise increasingly favors RDN, justification of sham-controlled trial designs will be revisited, and novel study designs may be required to evaluate the safety and efficacy of novel devices and procedures intended to address the escalating prevalence of poorly controlled hypertension.

Machine Learning Clustering for Blood Pressure Variability Applied to Systolic Blood Pressure Intervention Trial (SPRINT) and the Hong Kong Community Cohort

Visit-to-visit blood pressure variability (BPV) has been shown to be a predictor of cardiovascular disease. We aimed to classify the BPV levels using different machine learning algorithms. Visit-to-visit blood pressure readings were extracted from the SPRINT study in the United States and eHealth cohort in Hong Kong (HK cohort). Patients were clustered into low, medium, and high BPV levels with the traditional quantile clustering and 5 machine learning algorithms including K-means. Clustering methods were assessed by Stability Index. Similarities were assessed by Davies-Bouldin Index and Silhouette Index. Cox proportional hazard regression models were fitted to compare the risk of myocardial infarction, stroke, and heart failure. A total of 8133 participants had average blood pressure measurement 14.7 times in 3.28 years in SPRINT and 1094 participants who had average blood pressure measurement 165.4 times in 1.37 years in HK cohort. Quantile clustering assigned one-third participants as high BPV level, but machine learning methods only assigned 10% to 27%. Quantile clustering is the most stable method (stability index: 0.982 in the SPRINT and 0.948 in the HK cohort) with some levels of clustering similarities (Davies-Bouldin Index: 0.752 and 0.764, respectively). K-means clustering is the most stable across the machine learning algorithms (stability index: 0.975 and 0.911, respectively) with the lowest clustering similarities (Davies-Bouldin Index: 0.653 and 0.680, respectively). One out of 7 in the population was classified with high BPV level, who showed to have higher risk of stroke and heart failure. Machine learning methods can improve BPV classification for better prediction of cardiovascular diseases.

Blood Pressure Variability and Therapeutic Implications in Hypertension and Cardiovascular Diseases

Blood pressure (BP) is characterized by continuous dynamic and spontaneous oscillations occurring over lifetime and defining the so-called blood pressure variability (BPV). BPV has been associated with target organ damage, cardiovascular (CV) risk and death, suggesting the use of BPV as a new target in hypertension management in addition to mean BP values lowering. The purpose of the review is to focus on the therapeutic implications of BPV and summarize the effects of different drug classes on various types of BPV. Despite most first-line antihypertensive medications contribute to reduce both short and long term BPV, calcium channel blockers (CCBs) as monotherapy or fixed-combination therapy appear to be the most effective on BPV control. Further randomized interventional trials are needed to investigate which drug combinations are most appropriate according to patient CV risk stratification, in order to improve their CV outcomes.

Effect of Intensive and Standard Clinic-Based Hypertension Management on the Concordance Between Clinic and Ambulatory Blood Pressure and Blood Pressure Variability in SPRINT

Background Blood pressure ( BP ) varies over time within individual patients and across different BP measurement techniques. The effect of different BP targets on concordance between BP measurements is unknown. The goals of this analysis are to evaluate concordance between (1) clinic and ambulatory BP , (2) clinic visit-to-visit variability and ambulatory BP variability, and (3) first and second ambulatory BP and to evaluate whether different clinic targets affect these relationships. Methods and Results The SPRINT (Systolic Blood Pressure Intervention Trial) ambulatory BP monitoring ancillary study obtained ambulatory BP readings in 897 participants at the 27-month follow-up visit and obtained a second reading in 203 participants 293±84 days afterward. There was considerable lack of agreement between clinic and daytime ambulatory systolic BP with wide limits of agreement in Bland-Altman plots of -21 to 34 mm Hg in the intensive-treatment group and -26 to 32 mm Hg in the standard-treatment group. Overall, there was poor agreement between clinic visit-to-visit variability and ambulatory BP variability with correlation coefficients for systolic and diastolic BP all <0.16. We observed a high correlation between first and second ambulatory BP ; however, the limits of agreement were wide in both the intensive group (-27 to 21 mm Hg) and the standard group (-23 to 20 mm Hg). Conclusions We found low concordance in BP and BP variability between clinic and ambulatory BP and second ambulatory BP . Results did not differ by treatment arm. These results reinforce the need for multiple BP measurements before clinical decision making.

Long-term blood pressure variability and development of chronic kidney disease in type 2 diabetes

OBJECTIVE

Long-term visit-to-visit SBP variability (VVV) has been shown to predict cerebro-cardiovascular events and end-stage renal disease in chronic kidney disease (CKD) patients. Whether SBP VVV is also a predictor of CKD development in diabetes is currently uncertain. We assessed the role of SBP VVV on the development of CKD in patients with type 2 diabetes (T2D) and hypertension in real life.

METHODS

Clinical records from 30 851 patients with T2D and hypertension, with normal estimated glomerular filtration rate (eGFR) and regular visits during a 4-year follow-up were analyzed. SBP variability was measured by three metrics: coefficient of variation; SD of the mean SBP and average absolute difference of successive values in each individual. CKD was defined as eGFR less than 60 and/or a reduction in eGFR at least 30% from baseline.

RESULTS

Over the 4-year follow-up, 9.7% developed eGFR less than 60 and 4.5% an eGFR reduction at least 30% from baseline. Several clinical characteristics (older age, male sex, SBP, DBP, albuminuria, glycated hemoglobin, insulin treatment) were related to intraindividual SBP variability. Patients with VVV in the upper quintile showed an increased risk of developing both components of CKD [adjusted odds ratio (OR) 1.21, P < 0.001 and 1.32, P < 0.001, respectively]. The multivariable adjusted ORs of SBP coefficient of variation quintiles 2-5 for the incidence of CKD were incrementally higher (OR 1.04, P = 0.601, OR 1.05, P = 0.520, OR 1.21, P < 0.017 and OR 1.42, P < 0.001 as compared with the first quintile).

CONCLUSION

Increased long-term BP variability predicts CKD in patients with T2D and hypertension.

Association of 24 h-systolic blood pressure variability and cardiovascular disease in patients with obstructive sleep apnea

Background

To evaluate association of 24 h–systolic blood pressure (SBP) variability and obstructive sleep apnea (OSA) as defined by the apnea-hypopnea index ≥5/h; and association of 24 h–SBP variability and prevalent cardiovascular disease (CVD) in OSA patients.

Methods

Participants underwent polysomongraphy to evaluate the presence of OSA, and 24 h–ambulatory blood pressure monitoring was applied to evaluate 24 h–SBP variability as indexed by weighted 24 h–standard deviation (SD) of SBP. Between-group differences were evaluated in participants with and without OSA. Participants with OSA were divided into high and low 24 h–SBP variability groups and between-group differences were evaluated.

Results

Mean age of 384 participants was 50 years old and 42.2% had OSA. Mean 24 h–systolic/diastolic BP were 130/78 mmHg, with mean weighted 24 h–SD of systolic/diastolic BP were 12.9/7.3 mmHg. Compared to those without OSA, OSA participants had higher clinic-, 24 h-, daytime- and nighttime-SBP, and weighted 24 h, daytime- and nighttime-SD of SBP. Age, prevalent CVD and OSA, usage of angiotensin converting enzyme inhibitor/angiotensin receptor blocker, calcium channel blocker and diuretic were significantly associated with 24 h–SBP variability. In OSA patients, compared to those with low variability, participants with high variability had higher weighted 24 h, daytime- and nighttime-SD of SBP. After adjusted for covariates including clinic-SBP and 24 h–SBP, per 1-SD increment weighted 24 h–SD of SBP was associated with 21% increased prevalent CVD.

Conclusions

Patients with newly-diagnosed OSA have higher 24 h–SBP variability compared to those without OSA; in OSA patients, increased 24 h–SBP variability is associated with increased prevalence of CVD.

Visit-to-visit variability of systolic blood pressure predicts all-cause mortality in patients received percutaneous coronary intervention with drug-eluting stents

Blood pressure (BP) and its variability are associated with atherosclerotic disease and cardiovascular events. The prognostic implications of outpatient clinic visit-to-visit blood pressure variability (BPV) are unknown in patients undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DES). A total of 1,463 patients undergoing PCI with DES were consecutively enrolled from January 2009 to December 2013. We analyzed the 1,234 patients, who measured clinic BP more than three times during the first year after PCI. The BPV is determined by standard deviation of systolic and diastolic BP, and coefficient of variation. Median follow-up duration was 905 days (interquartile range 529-1,310 days). All patients were divided into two groups according to the coefficient of variation of systolic BP (CVSBP); high CVSBP group (> 8.78, n = 617) and low CVSBP group (≤ 8.78, n = 617). High CVSBP group had significantly higher all-cause mortality (7.9% versus 3.1%, p < 0.001) and composite of all-cause mortality, myocardial infarction, and stroke (13.1% versus 6.2%, p < 0.001). In multivariate logistic regression analysis for prediction of all-cause mortality, and composite of all-cause mortality, myocardial infarction, and stroke after PCI with DES, hazard ratios of high CVSBP group were 2.441 (95% of confidence interval 1.042-5.718, p = 0.040), and 1.980 (95% of confidence interval 1.125-3.485, p = 0.018). The higher visit-to-visit BPV is associated higher mortality in patients undergoing PCI with DES. The clinic measured visit-to-visit BPV may serve as a predictor of all-cause mortality after PCI with DES.

Visit-to-visit blood pressure variability is a risk factor for all-cause mortality and cardiovascular disease: a systematic review and meta-analysis

OBJECTIVE

Clinical cohort studies have reported that visit-to-visit variability (VVV) of blood pressure (BP) is associated with cardiovascular disease (CVD) or mortality. However, the results were not consistent in all studies. The current study is, therefore, aimed to conduct a systematic review and meta-analysis to determine the association between VVV of BP and CVD and all-cause mortality.

METHOD

PubMed and EMBASE were searched through 18 May 2014, using the following terms: VVV, BP, CVD, coronary heart disease (CHD), myocardial ischemia, stroke, and mortality. Overall, 84 records were identified, and 23 publications were enrolled into the current study. Data were extracted from selected publications, and meta-analysis was performed using a random effect model.

RESULT

VVV of SBP was significantly associated with outcomes of all-cause mortality with the relative risk (RR) and 95% confidence interval (CI) 1.14 (1.09, 1.18), CVD incidence (RR = 1.12, 95% CI: 1.05, 1.09), CVD mortality (RR = 1.18, 95% CI: 1.09, 1.28), CHD incidence (RR = 1.12, 95% CI: 1.06, 1.19), and stroke incidence (RR = 1.34, 95% CI: 1.11, 1.61).

CONCLUSION

In summary, among the wide heterogenetic population, modest associations between VVV of SBP and all-cause mortality, CVD incidence, CVD mortality, CHD incidence, and stroke incidence were found. Findings of the current study suggested that standardized approaches of monitoring VVV in the high-risk population, including patients with cardiac infarction, diabetes, stroke, and patients with chronic kidney disease or in dialysis, are necessary in designing a prospective clinical study on the association of VVV and patients' prognosis.

Methodology and technology for peripheral and central blood pressure and blood pressure variability measurement: current status and future directions - Position statement of the European Society of Hypertension Working Group on blood pressure monitoring and cardiovascular variability

Office blood pressure measurement has been the basis for hypertension evaluation for almost a century. However, the evaluation of blood pressure out of the office using ambulatory or self-home monitoring is now strongly recommended for the accurate diagnosis in many, if not all, cases with suspected hypertension. Moreover, there is evidence that the variability of blood pressure might offer prognostic information that is independent of the average blood pressure level. Recently, advancement in technology has provided noninvasive evaluation of central (aortic) blood pressure, which might have attributes that are additive to the conventional brachial blood pressure measurement. This position statement, developed by international experts, deals with key research and practical issues in regard to peripheral blood pressure measurement (office, home, and ambulatory), blood pressure variability, and central blood pressure measurement. The objective is to present current achievements, identify gaps in knowledge and issues concerning clinical application, and present relevant research questions and directions to investigators and manufacturers for future research and development (primary goal).

Impact of Visit-to-Visit Variability in Systolic Blood Pressure on Cardiovascular Outcomes in Korean National Health Insurance Service-National Sample Cohort

BACKGROUND

Despite an association between visit-to-visit blood pressure (BP) variability (VV-BPV) and cardiovascular (CV) outcomes, many studies performed during the past 4 years have shown conflicting results. This study investigated the impact of VV-BPV on CV outcomes in the Korean National Health Insurance Service (NHIS) database-National Sample Cohort.

METHODS

From the 2002 Korean NHIS database (n = 47,851,928), sample subjects with 3 or more BP measurements (n = 51,811) were divided into 2 groups according to a 10 mm Hg cutoff in the SD of systolic BP (SD-SBP). The CV outcomes of these groups were compared by sensitivity analyses using various sampling methods.

RESULTS

Irrespective of sampling method, subjects with SD-SBPs ≥10 mm Hg had higher rates of CV events or death, nonfatal myocardial infarction (MI) or stroke, and total mortality, but were not associated with CV mortality. The hazard ratios for CV events or death, nonfatal MI or stroke, CV mortality, and total mortality were 1.43 (95% confidence interval [CI], 1.25-1.63, P < 0.01), 1.45 (95% CI, 1.27-1.65, P < 0.01), 1.32 (95% CI, 0.89-1.94, P = 0.17), and 1.18 (95% CI, 1.01-1.38, P = 0.04), respectively.

CONCLUSIONS

Increased VV-BPV was an independent risk factor for future CV outcomes, independent of mean BP status, even in normotensive subjects and in all subgroups, except females. Similar VV-BPV values in the sensitivity analyses suggest VV-BPV is a reproducible phenomenon, reflecting the various types of intrinsic physiologic properties.

Long-Term Visit-to-Visit Blood Pressure Variability and Renal Function Decline in Patients With Hypertension Over 15 Years

BACKGROUND

Visit-to-visit variability of systolic blood pressure (SBP) has been shown to contribute to cardiovascular events and all-cause mortality. However, little is known about its long-term effect on renal function. We aim to examine the relationship between visit-to-visit blood pressure variability (BPV) and decline in renal function in patients with hypertension and to determine the level of systolic BPV that is associated with significant renal function decline.

METHODS AND RESULTS

This is a 15-year retrospective cohort study of 825 hypertensive patients. Blood pressure readings every 3 months were retrieved from the 15 years of clinic visits. We used SD and coefficient of variation as a measure of systolic BPV. Serum creatinine was captured and estimated glomerular filtration rate was calculated at baseline, 5, 10, and 15 years. The mean SD of SBP was 14.2±3.1 mm Hg and coefficient of variation of SBP was 10.2±2%. Mean for estimated glomerular filtration rate slope was -1.0±1.5 mL/min per 1.73 m2 per year. There was a significant relationship between BPV and slope of estimated glomerular filtration rate (SD: r=-0.16, P<0.001; coefficient of variation: r=-0.14, P<0.001, Pearson's correlation). BPV of SBP for each individual was significantly associated with slope of estimated glomerular filtration rate after adjustment for mean SBP and other confounders. The cutoff values estimated by the receiver operating characteristic curve for the onset of chronic kidney disease for SD of SBP was 13.5 mm Hg and coefficient of variation of SBP was 9.74%.

CONCLUSIONS

Long-term visit-to-visit variability of SBP is an independent determinant of renal deterioration in patients with hypertension. Hence, every effort should be made to reduce BPV in order to slow down the decline of renal function.

Blood Pressure Variability and Prediction of Target Organ Damage in Patients With Uncomplicated Hypertension

BACKGROUND

The average of multiple blood pressure (BP) readings (mean BP) independently predicts target organ damage (TOD). Observational studies have also shown an independent relationship between BP variability (BPV) and TOD, but there is limited longitudinal data. This study aimed to determine the effects of changes in mean BP levels compared with BPV on left ventricular mass index (LVMI) and aortic pulse wave velocity (aPWV).

METHODS

Mean BP levels (research-protocol clinic BP (clinic BP), 24-hour ambulatory BP, and 7-day home BP) and BPV were assessed in 286 patients with uncomplicated hypertension (mean age 64±8 SD years, 53% women) over 12 months. Reading-to-reading BPV (from 24-hour ambulatory BP) and day-to-day BPV (from 7-day home BP) were assessed at baseline and 12 months, and visit-to-visit BPV (clinic BP) was assessed from 5 visits over 12 months. LVMI was measured by 3D echocardiography and aPWV with applanation tonometry.

RESULTS

The strongest predictors of the changes in LVMI (ΔLVMI) were the changes in mean 24-hour systolic BPs (SBPs) (P < 0.02). Similarly, the strongest predictors of the changes in aPWV (ΔaPWV) were the changes in mean 24-hour ambulatory SBPs (P < 0.01) and the changes in mean clinic SBP (P < 0.001). However, none of the changes in BPV were independently associated with ΔLVMI or ΔaPWV (P > 0.05 for all).

CONCLUSIONS

Changes in mean BP levels, but not BPV, were most relevant to changes in TOD in patients with uncomplicated hypertension. Thus, from this point of view, BPV appears to have limited clinical utility in this patient population.

Hypertension, Blood Pressure Variability, and Target Organ Lesion

Hypertensive patients have a higher risk of developing health complications, particularly cardiovascular (CV) events, than individuals with normal blood pressure (BP). Severity of complications depends on the magnitude of BP elevation and other CV risk factors associated with the target organ damage. Therefore, BP control and management of organ damage may contribute to reduce this risk. BP variability (BPV) has been considered a physiological marker of autonomic nervous system control and may be implicated in increased CV risk in hypertension. This review will present some evidence relating BPV and target organ damage in hypertension in clinical and experimental settings.

Blood pressure variability and cardiovascular disease: systematic review and meta-analysis

OBJECTIVE

 To systematically review studies quantifying the associations of long term (clinic), mid-term (home), and short term (ambulatory) variability in blood pressure, independent of mean blood pressure, with cardiovascular disease events and mortality.

DATA SOURCES

 Medline, Embase, Cinahl, and Web of Science, searched to 15 February 2016 for full text articles in English.

ELIGIBILITY CRITERIA FOR STUDY SELECTION

 Prospective cohort studies or clinical trials in adults, except those in patients receiving haemodialysis, where the condition may directly impact blood pressure variability. Standardised hazard ratios were extracted and, if there was little risk of confounding, combined using random effects meta-analysis in main analyses. Outcomes included all cause and cardiovascular disease mortality and cardiovascular disease events. Measures of variability included standard deviation, coefficient of variation, variation independent of mean, and average real variability, but not night dipping or day-night variation.

RESULTS

 41 papers representing 19 observational cohort studies and 17 clinical trial cohorts, comprising 46 separate analyses were identified. Long term variability in blood pressure was studied in 24 papers, mid-term in four, and short-term in 15 (two studied both long term and short term variability). Results from 23 analyses were excluded from main analyses owing to high risks of confounding. Increased long term variability in systolic blood pressure was associated with risk of all cause mortality (hazard ratio 1.15, 95% confidence interval 1.09 to 1.22), cardiovascular disease mortality (1.18, 1.09 to 1.28), cardiovascular disease events (1.18, 1.07 to 1.30), coronary heart disease (1.10, 1.04 to 1.16), and stroke (1.15, 1.04 to 1.27). Increased mid-term and short term variability in daytime systolic blood pressure were also associated with all cause mortality (1.15, 1.06 to 1.26 and 1.10, 1.04 to 1.16, respectively).

CONCLUSIONS

 Long term variability in blood pressure is associated with cardiovascular and mortality outcomes, over and above the effect of mean blood pressure. Associations are similar in magnitude to those of cholesterol measures with cardiovascular disease. Limited data for mid-term and short term variability showed similar associations. Future work should focus on the clinical implications of assessment of variability in blood pressure and avoid the common confounding pitfalls observed to date.

SYSTEMATIC REVIEW REGISTRATION

 PROSPERO CRD42014015695.

Labile and Paroxysmal Hypertension: Common Clinical Dilemmas in Need of Treatment Studies

Although "labile hypertension" is regularly encountered by clinicians, there is a paucity of information available to guide therapeutic decisions. This review discusses its clinical relevance, the limitations of current knowledge, and possible directions for future research and clinical management. Results of studies that assessed measures of blood pressure variability or reactivity are reviewed. The limited information about effects of antihypertensive drugs on blood pressure variability is discussed. Two different clinical presentations are differentiated: labile hypertension and paroxysmal hypertension. Labile hypertension remains a clinical impression without defined criteria or treatment guidance. Paroxysmal hypertension, also called pseudopheochromocytoma, presents as dramatic episodes of abrupt and severe blood pressure elevation. The disorder can be disabling. Although it regularly raises suspicion of a pheochromocytoma, such a tumor is found in <2 % of patients. The cause, which involves both emotional factors and the sympathetic nervous system, and treatment approaches, are presented.

Is It Daily, Monthly, or Yearly Blood Pressure Variability that Enhances Cardiovascular Risk?

Variability is a phenomenon common to most biological processes that we can measure and is a particular feature of blood pressure (BP). Variability causes concern for many physicians regarding its clinical meaning and potential impact on cardiovascular risk. In this review, we assess the role of different time periods of blood pressure variability (BPV) in cardiovascular risk stratification. We review the indices of BPV derived from ambulatory blood pressure measurement (ABPM), home blood pressure measurement (HBPM), or at the clinic setting with the intention of providing a clear message for clinical practice. BPV, either derived from ABPM or HBPM, does not consistently augment cardiovascular risk prediction over and beyond that of average BP, particularly in low-risk individuals. That said, it would seem that certain medications such as calcium channel blockers may have a beneficial effect on visit-to-visit BPV and perhaps reduce the associated cardiovascular risk. This highlights the benefits in using combination therapy which might couple a number of therapeutic benefits such as the reductions of mean blood pressure and BPV. Overall, we should remain aware that the average BP level remains the main modifiable risk factor derived from BP measurements and continue to improve the control of hypertension and adverse health outcomes.

The Association Between Antihypertensive Medication Nonadherence and Visit-to-Visit Variability of Blood Pressure: Findings From the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial

Low adherence to antihypertensive medication has been hypothesized to increase visit-to-visit variability (VVV) of blood pressure (BP). We assessed the association between antihypertensive medication adherence and VVV of BP in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). VVV of BP was calculated using SD independent of mean, SD, and average real variability across study visits conducted 6 to 28 months after randomization. Participants who reported taking <80% of their antihypertensive medication at ≥1 study visits were categorized as nonadherent. Participants were followed up for cardiovascular events and mortality after the assessment of adherence and VVV of BP. SD independent of mean of BP was higher for nonadherent (n=2912) versus adherent (n=16 878) participants; 11.4±4.9 versus 10.5±4.5 for systolic BP; 6.8±2.8 versus 6.2±2.6 for diastolic BP (each P<0.001). SD independent of mean of BP remained higher among nonadherent than among adherent participants after multivariable adjustment (0.8 [95% confidence interval, 0.7-1.0] higher for systolic BP and 0.4 [95% confidence interval, 0.3-0.5] higher for diastolic BP]. SD and average real variability of systolic BP and diastolic BP were also higher among nonadherent than among adherent participants. Adjustment for nonadherence did not explain the association of VVV of BP with higher fatal coronary heart disease or nonfatal myocardial infarction, stroke, heart failure, or mortality risk. In conclusion, improving medication adherence may lower VVV of BP. However, VVV of BP is associated with cardiovascular outcomes independent of medication adherence.

Visit-to-Visit Variability of Systolic Blood Pressure and Cardiovascular Disease

Visit-to-visit variability of blood pressure (VVV of BP) is gaining interest as a prognostic marker for stroke, cardiovascular disease, and all-cause mortality. In this review, we discuss different metrics used to define VVV of BP, explore the potential sources of this phenomenon including patient characteristics and antihypertensive medication classes, and discuss recent evidence of its relation with cardiovascular outcomes. Current evidence relies on secondary analyses of clinical trials or on observational studies, none of which was designed to examine VVV of BP specifically. More research is required to develop standardized definitions of VVV of BP, to confirm the value of VVV as a prognostic indicator, and to ascertain whether efforts to reduce VVV of BP in addition to mean BP will improve outcomes.

Blood pressure variability: assessment, predictive value, and potential as a therapeutic target

A large body of evidence has consistently supported the relationship between blood pressure (BP) levels and the risk of cardiovascular complications. In recent years, several independent studies have also indicated that this risk may not only depend on the magnitude of the blood pressure elevation per se but also on the presence of other associated conditions such as increased blood pressure variability. This concept has been supported by a series of reports, most of which post hoc analyses of clinical trials in hypertension, showing that increasing values of BP variability (BPV) (either in the short term, in the midterm, or in the long term) may predict development, progression, and severity of cardiac, vascular, and renal organ damage, as well as cardiovascular events and mortality. Remarkably, studies conducted in populations at high cardiovascular risk have shown increasing values of BPV in the individual subjects (so-called intra- or within-individual BPV) to be strong predictors of cardiovascular morbidity and mortality, even to a larger extent than average BP values. However, in subjects at low to moderate cardiovascular risk, the contribution of BPV to cardiovascular risk prediction over and beyond average BP values has been shown to be only moderate. The aim of this paper is to critically review the evidence addressing the prognostic relevance of different components of BPV addressing a yet open question, i.e., whether routine assessment of BPV in clinical practice should be regarded as an additional target of antihypertensive treatment to improve cardiovascular protection.

Development of an Experimental Model to Study the Relationship Between Day-to-Day Variability in Blood Pressure and Aortic Stiffness

We aimed to develop an animal model of long-term blood pressure variability (BPV) and to investigate its consequences on aortic damage. We hypothesized that day-to-day BPV produced by discontinuous treatment of spontaneously hypertensive rats (SHR) by valsartan may increase arterial stiffness. For that purpose, rats were discontinuously treated, 2 days a week, or continuously treated by valsartan (30 mg/kg/d in chow) or placebo. Telemetered BP was recorded during 2 min every 15 min, 3 days a week during 8 weeks to cover the full BP variations in response to the treatment schedule. Pulse wave velocity (PWV) and aortic structure evaluated by immunohistochemistry were investigated in a second set of rats treated under the same conditions. Continuous treatment with valsartan reduced systolic BP (SBP) and reversed the aortic structural alterations observed in placebo treated SHR (decrease of medial cross-sectional area). Discontinuous treatment with valsartan decreased SBP to a similar extent but increased the day-to-day BPV, short term BPV, diastolic blood pressure (DBP), and PWV as compared with continuous treatment. Despite no modifications in the elastin/collagen ratio and aortic thickness, an increase in PWV was observed following discontinuous treatment and was associated with a specific accumulation of fibronectin and its α_v-integrin receptor compared with both groups of rats. Taken together the present results indicate that a discontinuous treatment with valsartan is able to induce a significant increase in day-to-day BPV coupled to an aortic phenotype close to that observed in hypertension. This experimental model should pave the way for future experimental and clinical studies aimed at assessing how long-term BPV increases aortic stiffness.

Understanding and treating hypertension in diabetic populations

Hypertension and diabetes frequently occurs in the same individuals in clinical practice. Moreover, the presence of hypertension does increase the risk of new-onset diabetes, as well as diabetes does promote development of hypertension. Whatever the case, the concomitant presence of these conditions confers a high risk of major cardiovascular complications and promotes the use integrated pharmacological interventions, aimed at achieving the recommended therapeutic targets. While the benefits of lowering abnormal fasting glucose levels in patients with hypertension and diabetes have been consistently demonstrated, the blood pressure (BP) targets to be achieved to get a benefit in patients with diabetes have been recently reconsidered. In the past, randomized clinical trials have, indeed, demonstrated that lowering BP levels to less than 140/90 mmHg was associated to a substantial reduction of the risk of developing macrovascular and microvascular complications in hypertensive patients with diabetes. In addition, epidemiological and clinical reports suggested that "the lower, the better" for BP in diabetes, so that levels of BP even lower than 130/80 mmHg have been recommended. Recent randomized clinical trials, however, designed to evaluate the potential benefits obtained with an intensive antihypertensive therapy, aimed at achieving a target systolic BP level below 120 mmHg as compared to those obtained with less stringent therapy, have challenged the previous recommendations from international guidelines. In fact, detailed analyses of these trials showed a paradoxically increased risk of coronary events, mostly myocardial infarction, in those patients who achieved the lowest BP levels, particularly in the high-risk subsets of hypertensive populations with diabetes. In the light of these considerations, the present article will briefly review the common pathophysiological mechanisms, the potential sites of therapeutic interactions and the currently recommended BP targets to be achieved under pharmacological treatment in hypertension and diabetes.

Visit-to-Visit Variability of Blood Pressure and Coronary Heart Disease, Stroke, Heart Failure, and Mortality: A Cohort Study

BACKGROUND

Variability of blood pressure (BP) across outpatient visits is frequently dismissed as random fluctuation around a patient's underlying BP.

OBJECTIVE

To examine the association of visit-to-visit variability (VVV) of systolic BP (SBP) and diastolic BP with cardiovascular disease (CVD) and mortality outcomes.

DESIGN

Prospective cohort study.

SETTING

Post hoc analysis of ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial).

PARTICIPANTS

25 814 ALLHAT participants.

MEASUREMENTS

The VVV of SBP was defined as the SD across SBP measurements obtained at 7 visits conducted from 6 to 28 months after ALLHAT enrollment. Participants without CVD events during the first 28 months of follow-up were followed from the 28-month visit through the end of active ALLHAT follow-up. Outcomes included fatal coronary heart disease (CHD) or nonfatal myocardial infarction, all-cause mortality, stroke, and heart failure.

RESULTS

During follow-up, 1194 fatal CHD or nonfatal MI events, 1948 deaths, 606 strokes, and 921 heart failure events occurred. After multivariable adjustment, including for mean SBP, the hazard ratio comparing participants in the highest versus lowest quintile of SD of SBP (≥14.4 mm Hg vs. <6.5 mm Hg) was 1.30 (95% CI, 1.06 to 1.59) for fatal CHD or nonfatal MI, 1.58 (CI, 1.32 to 1.90) for all-cause mortality, 1.46 (CI, 1.06 to 2.01) for stroke, and 1.25 (CI, 0.97 to 1.61) for heart failure. Higher VVV of diastolic BP was also associated with CVD events and mortality.

LIMITATION

Long-term outcomes were not available.

CONCLUSION

Higher VVV of SBP is associated with an increased risk for CVD and mortality. Future studies should examine whether reducing VVV of BP lowers this risk.

PRIMARY FUNDING SOURCE

National Institutes of Health.

Association Between Visit-to-Visit Variability in Blood Pressure and Cardiovascular Events in Hypertensive Patients After Successful Percutaneous Coronary Intervention

Background

Visit-to-visit variability (VVV) in blood pressure (BP) in addition to high BP has been shown to be a strong predictor of coronary events and stroke. Therefore, we investigated the associations between VVV in BP or BP levels and cardiovascular events after successful percutaneous coronary intervention (PCI).

Methods

We enrolled 176 hypertensive patients who had undergone successful PCI and who had four clinic visits to measure BP until follow-up coronary angiography (CAG) at 6 - 9 months after PCI. The patients were divided into those with acute coronary syndrome (ACS group; n = 50) and those with stable angina pectoris (SAP group; n = 126). We determined VVV in BP expressed as the standard deviation (SD) of average BP, average, and the maximum and minimum BP during the follow-up period. Major adverse cardiovascular events (MACEs) (myocardial infarction (MI), target lesion revascularization (TLR) and all-cause death) were also analyzed.

Results

There were no significant differences in VVV in BP, average BP or maximum or minimum BP between the patients with and without MACE in all patients, the ACS and SAP groups. Interestingly, in the ACS group, VVV in SBP and maximum SBP in patients with MI were significantly higher than those in patients without MI. The cut-off levels for VVV in BP and maximum SBP that gave the greatest sensitivity and specificity for MI in the ACS group were 15.1 and 138 mm Hg, respectively.

Conclusion

Higher VVV in SBP and maximum SBP in patients with ACS after successful PCI were associated with the onset of MI.

Prognostic significance of visit-to-visit systolic blood pressure variability: a meta-analysis of 77,299 patients

In recent clinical investigations, visit-to-visit systolic blood pressure (SBP) variability was proven as a predictor of cardiovascular events and all-cause mortality. However, inconsistent results exist in this association. A meta-analysis of 13 prospective studies was conducted to evaluate the prognostic value of visit-to-visit SBP variability by different parameters in 77,299 patients with a mean follow-up of 6.3 years. The pooled age- and mean SBP-adjusted hazard ratios (HRs) for all-cause mortality were 1.03 (95% confidence interval [CI], 1.02-1.04; P<.001) per 1-mm Hg increase in SBP standard deviation (SD) and 1.04 (1.02-1.06, P<.001) per 1% in SBP coefficient of variation, and the corresponding values of cardiovascular mortality were 1.10 (1.02-1.17, P<.001) and 1.01 (0.99-1.03, P=.32), respectively. Moreover, a 1-mm Hg increase in SD was significantly associated with stroke, with an HR of 1.02 (1.01-1.03, P<.001). Visit-to-visit SBP variability, independent of age and mean SBP, is a predictor of cardiovascular and all-cause mortality and stroke.

Measurement of blood pressure variability and the clinical value

Authors have collected and analyzed literature data on blood pressure variability. They present the methods of blood pressure variability measurement, clinical value and relationships with target organ damages and risk of presence of cardiovascular events. They collect data about the prognostic value of blood pressure variability and the effects of different antihypertensive drugs on blood pressure variability. They underline that in addition to reduction of blood pressure to target value, it is essential to influence blood pressure fluctuation and decrease blood pressure variability, because blood pressure fluctuation presents a major threat for the hypertensive subjects. Data from national studies are also presented. They welcome that measurement of blood pressure variability has been included in international guidelines. Orv. Hetil., 2014, 155(42), 1661–1672.

Effect of long-term antihypertensive treatment on white-coat hypertension

Limited evidence is available on the extent and frequency by which antihypertensive treatment lowers office blood pressure (BP) in white-coat hypertension (WCH). Data are even more scanty and discrepant on the corresponding effect on ambulatory BP (ABP). In the hypertensive patients of the European Lacidipine Study on Atherosclerosis (ELSA), office and ABP were measured before treatment and at 6-month (office BP) or 12-month (ABP) intervals during the 4-year administration of calcium channel blocker-based or β-blocker-based treatment. The two groups were pooled and data were analyzed separately in patients with both office and ABP elevation (n=1670; sustained hypertension) or WCH (n=251; office BP elevation only). In sustained hypertension, office and 24-hour mean systolic BP were both markedly reduced through the treatment period, the mean change being -20.0±12.5 and -10.1±11.0 mm Hg, respectively (P<0.0001 for both). In striking contrast, in WCH the office BP reduction was almost as marked as in sustained hypertension (-19.1±11.2 mm Hg; P<0.0001), whereas 24-hour systolic BP values showed no fall or a slight progressive significant increase, its mean change during treatment being 1.6±8.6 mm Hg (P=0.007). Lowering of office BP occurred at a lower treatment intensity in WCH than in sustained hypertension. Similar findings were obtained for diastolic BP. In WCH, antihypertensive treatment should not be expected to have a lowering effect on ABP, even when office BP undergoes a concomitant marked and persistent reduction. The consequence of this contrasting effect on the incidence of hypertension-related outcomes remains to be established.

Stroke outcomes among participants randomized to chlorthalidone, amlodipine or lisinopril in ALLHAT

The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) was a randomized, double-blind, practice-based, active-control, comparative effectiveness trial in 33,357 high-risk hypertensive participants. ALLHAT compared cardiovascular disease outcomes in participants initially treated with an angiotensin-converting enzyme inhibitor (lisinopril), a calcium channel blocker (amlodipine), or a thiazide-type diuretic (chlorthalidone). We report stroke outcomes in 1517 participants in-trial and 1596 additional participants during post-trial passive surveillance, for a total follow-up of 8-13 years. Stroke rates were higher with lisinopril (6-year rate/100 = 6.4) than with chlorthalidone (5.8) or amlodipine (5.5) in-trial but not including post-trial (10-year rates/100 = 13.2 [chlorthalidone], 13.1[amlodipine], and 13.7 [lisinopril]). In-trial differences were driven by race (race-by-lisinopril/chlorthalidone interaction P = .005, race-by-amlodipine/lisinopril interaction P = .012) and gender (gender-by-lisinopril/amlodipine interaction P = .041), separately. No treatment differences overall, or by race or gender, were detected over the 10-year period. No differences appeared among treatment groups in adjusted risk of all-cause mortality including post-trial for participants with nonfatal in-trial strokes. Among Blacks and women, lisinopril was less effective in preventing stroke in-trial than either chlorthalidone or amlodipine, even after adjusting for differences in systolic blood pressure. These differences abated by the end of the post-trial period.

Visit-to-visit variability of blood pressure and cardiovascular disease and all-cause mortality: a systematic review and meta-analysis

Visit-to-visit variability of blood pressure (BP) has been associated with cardiovascular disease (CVD) and mortality in some but not all studies. We conducted a systematic review and meta-analysis to examine the association between visit-to-visit variability of BP and CVD and all-cause mortality. Medical databases were searched through June 4, 2014, for studies meeting the following eligibility criteria: adult participants; BP measurements at ≥3 visits; follow-up for CVD, coronary heart disease, stroke, or mortality outcomes; events confirmed via database, death certificate, or event ascertainment committee; and adjustment for confounders. Data were extracted by 2 reviewers and pooled using a random-effects model. Overall, 8870 abstracts were identified of which 37 studies, representing 41 separate cohorts, met inclusion criteria. Across studies, visit-to-visit variability of systolic BP and diastolic BP showed significant associations with outcomes in 181 of 312 (58.0%) and 61 of 188 (32.4%) analyses, respectively. Few studies provided sufficient data for pooling risk estimates. For each 5 mm Hg higher SD of systolic BP, the pooled hazard ratio for stroke across 7 cohorts was 1.17 (95% confidence interval [CI], 1.07-1.28), for coronary heart disease across 4 cohorts was 1.27 (95% CI, 1.07-1.51), for CVD across 5 cohorts was 1.12 (95% CI, 0.98-1.28), for CVD mortality across 5 cohorts was 1.22 (95% CI, 1.09-1.35), and for all-cause mortality across 4 cohorts was 1.20 (95% CI, 1.05-1.36). In summary, modest associations between visit-to-visit variability of BP and CVD and all-cause mortality are present in published studies. However, these findings are limited by the small amount of data available for meta-analysis.

Heritability analyses show visit-to-visit blood pressure variability reflects different pathological phenotypes in younger and older adults: evidence from UK twins

BACKGROUND

Clinic and long-term average blood pressure (BP) are heritable traits with estimates of heritability ranging from 0.31 to 0.68. Long-term visit-to-visit BP variability (BPV) is emerging as a new cardiovascular risk predictor, though it is unclear if this is completely independent of BP. We hypothesize that BPV should demonstrate the same pattern of additive genetic, shared environmental and unique environmental variance as BP, if both are phenotypic surrogates.

METHOD

We studied 2889 twin pairs not on any BP-lowering therapy from the Twins UK cohort, and estimated the additive genetic variance for baseline BP, long-term average BP, BP trajectory (rate of change of BP in mmHg/year) and BPV (coefficient of variation and average real variability over an average of 3.2 visits). Heritability estimates were obtained by structural equation modelling adjusting for age, age, sex and BMI.

RESULTS

The heritabilities for baseline SBP and DBP were 0.51 (95% confidence interval 0.49, 0.53) and 0.56 (0.54, 0.58); long-term average SBP and DBP were 0.56 (0.53, 0.59) and 0.61 (0.58, 0.64); and systolic and diastolic trajectories over 10 years were 0.49 (0.46, 0.52) and 0.29 (0.27, 0.32), respectively. Both overall systolic and diastolic BPV showed no additive genetic variance contributing to the phenotypic variation, but after stratification by age, the younger subgroup (<51 years) showed heritability estimates of 0.44 (0.38, 0.50) for coefficient of variation and 0.35 (0.29, 0.41) for average real variability.

CONCLUSION

Age is a major factor that influences heritability estimation of BPV and it is likely that BPV in younger and older age groups may reflect different pathological phenotypes.