Variability in systolic blood pressure--a risk factor for coronary heart disease?

Predictive ability of visit-to-visit blood pressure indices for adverse events in patients with non-valvular atrial fibrillation: Subanalysis of the J-RHYTHM Registry

Background

We previously reported that standard deviation (SD) of systolic blood pressure (SBP), an index of BP variability, and SBP-time in target range (TTR), an index of BP consistency, were significantly associated with adverse events in patients with non-valvular atrial fibrillation (NVAF). Thus, this study aimed to compare predictive ability for adverse events among visit-to-visit BP variability/consistency indices using data from the J-RHYTHM Registry.

Methods

Of 7406 outpatients with NVAF, 7226 (age, 69.7 ± 9.9 years; men, 70.7%), in whom BP was measured 4 times or more (14.6 ± 5.0 times) during the 2-year follow-up period or until occurrence of an event, were included. As BP consistency for target SBP between 110 and 130 mmHg, SBP-TTR by the Rosendaal method and SBP-frequency in range (FIR) were calculated. Predictive ability was expressed by the area under receiver-operating-characteristic curve (AUC). AUCs of SBP-TTR and SBP-FIR for adverse events were compared with those of SBP-SD by the DeLong's test.

Results

SBP-SD, SBP-TTR, and SBP-FIR were 11.0 ± 4.2 mmHg, 49.5 ± 28.3%, and 52.3 ± 23.0%, respectively. AUCs of these indices for thromboembolism, major hemorrhage, and all-cause death were 0.62, 0.64, and 0.63 for SBP-SD; 0.56, 0.55, and 0.56 for SBP-TTR; and 0.55, 0.56, and 0.58 for SBP-FIR; respectively. AUCs of SBP-SD were significantly larger than those of SBP-TTR for major hemorrhage (P = 0.010) and all-cause death (P = 0.014), and SBP-FIR for major hemorrhage (P = 0.016).

Conclusion

Among visit-to-visit BP variability/consistency indices, predictive ability of SBP-SD for major hemorrhage and all-cause death was superior to that of SBP-TTR and SBP-FIR in patients with NVAF.

Association Between Systolic Blood Pressure Variability and Major Adverse Cardiovascular Events in Korean Patients With Chronic Kidney Disease: Findings From KNOW-CKD

Background Whether visit-to-visit systolic blood pressure (SBP) variability can predict major adverse cardiovascular events (MACE) in patients with chronic kidney disease is unclear. Methods and Results We investigated the relationship between SDs of visit-to-visit SBP variability during the first year of enrollment and MACE among 1575 participants from KNOW-CKD (Korean Cohort Study for Outcome in Patients With Chronic Kidney Disease). Participants were categorized into 3 groups according to tertiles of visit-to-visit SBP variability (SD). The study end point was MACE, defined as a composite of nonfatal myocardial infarction, unstable angina, revascularization, nonfatal stroke, hospitalization for heart failure, or cardiac death. During 6748 patient-years of follow-up (median, 4.2 years), MACE occurred in 64 participants (4.1%). Compared with the lowest tertile of visit-to-visit SBP variability (SD), the hazard ratios (HRs) for the middle and the highest tertile were 1.64 (95% CI, 0.80-3.36) and 2.23 (95% CI, 1.12-4.44), respectively, in a multivariable cause-specific hazard model. In addition, the HR associated with each 5-mm Hg increase in visit-to-visit SBP variability (SD) was 1.21 (95% CI, 1.01-1.45). This association was consistent in sensitivity analyses with 2 additional definitions of SBP variability determined by the coefficient of variation and variation independent of the mean. The corresponding HRs for the middle and highest tertiles were 2.11 (95% CI, 1.03-4.35) and 2.28 (95% CI, 1.12-4.63), respectively, in the analysis with the coefficient of variation and 1.76 (95% CI, 0.87-3.57) and 2.04 (95% CI, 1.03-4.03), respectively, with the variation independent of the mean. Conclusions Higher visit-to-visit SBP variability is associated with an increased risk of MACE in patients with chronic kidney disease. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01630486.

Modelling of longitudinal data to predict cardiovascular disease risk: a methodological review

OBJECTIVE

The identification of methodology for modelling cardiovascular disease (CVD) risk using longitudinal data and risk factor trajectories.

METHODS

We screened MEDLINE-Ovid from inception until 3 June 2020. MeSH and text search terms covered three areas: data type, modelling type and disease area including search terms such as "longitudinal", "trajector*" and "cardiovasc*" respectively. Studies were filtered to meet the following inclusion criteria: longitudinal individual patient data in adult patients with ≥3 time-points and a CVD or mortality outcome. Studies were screened and analyzed by one author. Any queries were discussed with the other authors. Comparisons were made between the methods identified looking at assumptions, flexibility and software availability.

RESULTS

From the initial 2601 studies returned by the searches 80 studies were included. Four statistical approaches were identified for modelling the longitudinal data: 3 (4%) studies compared time points with simple statistical tests, 40 (50%) used single-stage approaches, such as including single time points or summary measures in survival models, 29 (36%) used two-stage approaches including an estimated longitudinal parameter in survival models, and 8 (10%) used joint models which modelled the longitudinal and survival data together. The proportion of CVD risk prediction models created using longitudinal data using two-stage and joint models increased over time.

CONCLUSIONS

Single stage models are still heavily utilized by many CVD risk prediction studies for modelling longitudinal data. Future studies should fully utilize available longitudinal data when analyzing CVD risk by employing two-stage and joint approaches which can often better utilize the available data.

Erythrocyte Indices and Long-term Blood Pressure Variability in Military Males

BACKGROUNDS

Severe microcytic anemia has been associated with BP changes.

AIMS AND OBJECTIVES

Whether the erythrocyte indices are associated with long-term BPV is unknown. This study aimed to investigate the association of hemoglobin levels and erythrocyte size with long-term blood pressure variability (BPV) in young males.

METHODS

This study included 1,112 healthy military males, averaging 32 years of age, in Taiwan. All participants took a measurement of systolic and diastolic BP (SBP and DBP) every two-year from 2012 to 2018 (2012-14, 2014-15, 2015-16, 2016-18). Lev-els of hemoglobin and mean corpuscular volume (MCV) of erythrocytes were obtained at the first visit. Long-term BPV was assessed by the standard deviation (SD) and aver-age real variability (ARV). Multivariate linear regression analysis with adjustment for the baseline BP levels and other covariates was used to elucidate the association.

RESULTS

Hemoglobin levels were borderline positively correlated with SD DBP (β and standard errors = 0.016 (0.009), P =0.06). In those with hemoglobin levels of 10.0-13.9 g/dL, hemoglobin was negatively correlated with SDSBP (β= -0.039 (0.018), P =0.03). In contrast, MCV levels were borderline positively correlated with SDSBP (β =0.085 (0.052), P =0.09). In those with MCV levels <80 fL, MCV was positively correlated with SDSBP and ARVSBP (β= 0.445 (0.210) and 0.286 (0.149), p = 0.03 and 0.05, re-spectively).

CONCLUSION

There were inconsistent patterns for the associations of erythrocyte indices with long-term BPV. We found a U-shaped relationship of hemoglobin levels with sys-tolic BPV, whereas there was a positive linear relationship of hemoglobin and MCV levels with diastolic BPV, respectively.

Visit-to-visit variability of blood pressure and cardiovascular events among the working-age population in Japan: findings from the Japan Epidemiology Collaboration on Occupational Health Study

Increased visit-to-visit variability (VVV) of blood pressure, which is calculated based on several readings, has been suggested to be a significant predictor of cardiovascular events and mortality, independent of mean blood pressure. This study examined associations between the VVV of systolic blood pressure (SBP) measured annually and cardiovascular disease (CVD) events among 72,617 Japanese subjects. Data were obtained from the Japan Epidemiology Collaboration on Occupational Health Study, which is an ongoing epidemiological survey of workers in Japan. VVV was calculated as the coefficient of variation of SBP readings from 2008 to 2011; information on fatal and nonfatal CVD events was collected from registries of specific outcomes between April 2012 and March 2019. A Cox proportional hazards model was applied to investigate associations after adjusting for mean SBP between 2008 and 2011 and covariates. During the 7-year follow-up period, there were 63 CVD fatalities and 314 CVD events (combining fatal and nonfatal events). The results showed that a one-standard deviation increase in VVV was associated with a significant increase in the risk of CVD mortality (hazard ratio [HR] = 1.42; 95% confidence interval [CI] = 1.32-1.54); those in the highest tertile had a 3.20 times (95% CI = 1.26-8.17) higher risk of CVD mortality than those in the lowest tertile. We found less pronounced associations regarding CVD events (HR = 1.08, 95% CI = 1.02-1.15). In conclusion, VVV was significantly associated with CVD mortality in our Japanese working population.

Variability of risk factors and diabetes complications

Several studies suggest that, together with glucose variability, the variability of other risk factors, as blood pressure, plasma lipids, heart rate, body weight, and serum uric acid, might play a role in the development of diabetes complications. Moreover, the variability of each risk factor, when contemporarily present, may have additive effects. However, the question is whether variability is causal or a marker. Evidence shows that the quality of care and the attainment of the target impact on the variability of all risk factors. On the other hand, for some of them causality may be considered. Although specific studies are still lacking, it should be useful checking the variability of a risk factor, together with its magnitude out of the normal range, in clinical practice. This can lead to an improvement of the quality of care, which, in turn, could further hesitate in an improvement of risk factors variability.

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.

Blood Pressure Variability and Dementia: A State-of-the-Art Review

Accumulating evidence demonstrates that blood pressure variability (BPV) may contribute to target organ damage, causing coronary heart disease, stroke, and renal disease independent of the level of blood pressure (BP). Several lines of evidence have also linked increased BPV to a higher risk of cognitive decline and incident dementia. The estimated number of dementia cases worldwide is nearly 50 million, and this number continues to grow with increasing life expectancy. Because there is no effective treatment to modify the course of dementia, targeting modifiable vascular factors continues as a top priority for dementia prevention. A clear understanding of the role of BPV in dementia may shed light on the etiology, early prevention, and novel therapeutic targets of dementia, and has therefore gained substantial attention from researchers and clinicians. This review summarizes state-of-art evidence on the relationship between BPV and dementia, with a specific focus on the epidemiological evidence, the underlying mechanisms, and potential intervention strategies. We also discuss challenges and opportunities for future research to facilitate optimal BP management and the clinical translation of BPV for the risk assessment and prevention of dementia.

Impact of Blood Pressure Visit-to-Visit Variability on Adverse Events in Patients With Nonvalvular Atrial Fibrillation: Subanalysis of the J-RHYTHM Registry

Background

Blood pressure (BP) variability has reportedly been a risk factor for various clinical events. To clarify the influence of BP visit‐to‐visit variability on adverse events in patients with nonvalvular atrial fibrillation, a post hoc analysis of the J‐RHYTHM Registry was performed.

Methods and Results

Of 7406 outpatients with nonvalvular atrial fibrillation from 158 institutions, 7226 (age, 69.7±9.9 years; men, 70.7%), in whom BP was measured 4 times or more (14.6±5.0 times) during the 2‐year follow‐up period or until occurrence of an event, constituted the study group. SD and coefficient of variation of BP values were calculated as BP variability. Thromboembolism, major hemorrhage, and all‐cause death occurred in 110 (1.5%), 121 (1.7%), and 168 (2.3%) patients, respectively. When patients were divided into quartiles of systolic BP‐SD (<8.20, 8.20–10.49, 10.50–13.19, and ≥13.20 mm Hg), hazard ratios (HRs) for all adverse events were significantly high in the highest quartile compared with the lowest quartile (HR, 2.00, 95% CI, 1.15–3.49, P=0.015 for thromboembolism; HR, 2.60, 95% CI, 1.36–4.97, P=0.004 for major hemorrhage; and HR, 1.85, 95% CI, 1.11–3.07, P=0.018 for all‐cause death) after adjusting for components of the CHA₂DS₂‐VASc score, warfarin and antiplatelet use, atrial fibrillation type, BP measurement times, and others. These findings were consistent when BP‐coefficient of variation was used instead of BP‐SD.

Conclusions

Systolic BP visit‐to‐visit variability was significantly associated with all adverse events in patients with nonvalvular atrial fibrillation. Further studies are needed to clarify the causality between BP variability and adverse outcomes in patients with nonvalvular atrial fibrillation.

Registration

URL: https://www.umin.ac.jp/ctr/; Unique Identifier: UMIN000001569.

Traditional Cardiovascular Risk Factors Strongly Underestimate the 5-Year Occurrence of Cardiovascular Morbidity and Mortality in Spinal Cord Injured Individuals

OBJECTIVES

To explore whether traditional models of cardiovascular disease (CVD) risk prediction correctly predict CVD events across a median 5.7-year follow-up period in individuals with spinal cord injury (SCI) and whether adding SCI-related characteristics (ie, lesion level) to the prediction model can improve the prognostic value.

DESIGN

Retrospective analysis of patient records.

SETTING

Observation at the start of active rehabilitation of participants in a multicenter cohort study, "Restoration of (Wheelchair) Mobility in SCI Rehabilitation," in the Netherlands.

PARTICIPANTS

Patients with SCI (N=200) The patients were 74% men, aged 40±14 years, and with an American Spinal Injury Association (ASIA) impairment score of A through D. Forty percent had tetraplegia, and 69% were motor complete.

INTERVENTIONS

Risk profiling/not applicable.

MAIN OUTCOME MEASURES

Survival status and cardiovascular morbidity and mortality qwere obtained from medical records. Five-year Framingham Risk Scores (FRS) and the FRS ability to predict events assessed using receiver operating characteristic (ROC) curves with corresponding areas under the curve (AUC) and 95% confidence intervals (CI). Kaplan-Meier curves and the log-rank test were used to assess the difference in clinical outcome between participants with an FRS score lower or higher than the median FRS score for the cohort. SCI-related factors associated with CVD events, ASIA impairment, motor completeness, level of injury, and sports participation before injury were explored using univariate and multivariate Cox proportional hazard regression.

RESULTS

The median 5-year FRS was 1.36%. Across a median follow-up period of 5.7 years, 39 developed a CVD event, including 10 fatalities. Although the FRS markedly underestimated the true occurrence of CVD events, the Kaplan-Meier curves and the log-rank test showed that the risk ratio for individuals with an FRS score less than the median FRS (eg, low risk) versus a score greater than the median FRS (high risk) was 3.2 (95% CI, 1.6-6.5; P=.001). Moreover, ROC with corresponding AUCs suggests acceptable accuracy of the FRS to identify individuals with increased risk for future CVD events (ROC AUC of 0.71; 95% CI, 0.62-0.82). Adding ASIA impairment (0.74; 95% CI, 0.66-0.82), motor impairment (0.74; 95% CI, 0.66-0.83), level of injury (0.72; 95% CI, 0.63-0.81), or active engagement in sport before injury (0.72; 95% CI, 0.63-0.88) to the FRS did not improve the level of discrimination.

CONCLUSIONS

Our 5.7-year retrospective study reveals that cardiovascular risk factors and risk models markedly underestimate the true risk for CVD events in individuals with SCI. Nonetheless, these markers successfully distinguish between SCI individuals at high versus low risk for future CVD events. Our data may have future clinical implications, both related to (cutoff values of) CVD risk factors, but also for (earlier) prescription of (non)pharmacologic strategies against CVD in SCI individuals.

Cardiovascular Risk Factors: It's Time to Focus on Variability!

Atherosclerotic heart disease remains a leading cause of morbidity and mortality worldwide. While extensive research supports cardiovascular risk factor reduction in the form of achieving evidence-based blood pressure, lipid, glucose, and body weight targets as a means to improve cardiovascular outcomes, residual risk remains. Emerging data have demonstrated that the intraindividual variability of these risk factor targets potentially contribute to this residual risk. It may therefore be time to define risk factor by not only its magnitude and duration as done traditionally, but perhaps also by the variability of that particular risk factor over time.

Risk Factor Variability and Cardiovascular Outcome: JACC Review Topic of the Week

Until recently, intraindividual visit-to-visit variability of cardiovascular risk factors has been dismissed as random fluctuation. This simplistic concept was challenged by demonstrating that visit-to-visit blood pressure variability, independent of average blood pressure, was a powerful risk factor for stroke. Subsequently, variability of other cardiovascular risk factors such as cholesterol, glycemia, and body weight was documented to increase risk independent of their absolute values. Variability of these risk factors has been demonstrated to be a powerful predictor for all-cause and cardiovascular mortality, stroke, coronary artery disease, heart failure, end-stage renal disease, and dementia. With the notable exception of heart rate, cardiovascular risk factors must now be defined by 2 components: the magnitude and duration of sustained risk factor elevation and, equally important, the variability of the same risk factor over time.

Factors Associated with Visit-to-Visit Variability of Blood Pressure Measured as Part of Routine Clinical Care among Patients Attending Cardiology Outpatient Department of a Tertiary Care Centre in Northern Sri Lanka

Visit-to-visit variability (VVV) is a relatively new concept in the hypertensive arena. Data regarding VVV are lacking in our region, and factors associated with VVV are rarely examined in previous studies. This study was conducted among 406 patients attended to the cardiology outpatient department of Teaching Hospital, Jaffna, Sri Lanka, in 2018 to assess the long-term variability of blood pressure (BP) by reviewing last six consecutive BP readings from the records retrospectively. Data regarding sociodemographic variables and behavioural factors such as medication adherence, physical activity, smoking, alcohol consumption, and relevant comorbidities were taken through an interviewer-administered questionnaire. Data were analysed by using SPSS version 25 and VVV of systolic blood pressure (SBP) matrix expressed as mean of SD and association were examined with various factors and VVV of SBP. SBP showed high VVV among the participants as expressed by mean of SD which was 13.06 ± 5.64. When comparing mean SD among the categories of different variables, female sex (P=0.023) and comorbidities such as diabetes mellitus (DM) (P=0.013), chronic kidney disease (CKD) (P=0.007), and risk of developing obstructive sleep apnoea (OSA) (P=0.04) showed significant variation. Medication adherence to prescribed hypertensive medication was a major issue even though significant association was not found with high VVV (P=0.536). The SD of SBP was then classified into high and low VVV groups by means of a cutoff point at the 50th percentile. Bivariate analysis by using Chi-squared test revealed comorbidities such as DM, CKD, and physical activity (P=0.044) were significantly associated with high VVV. Further multivariate regression analysis revealed that comorbidities such as DM and CKD have 1.561 times and 5.999 times more risk to show high variability, respectively. In conclusion, we recommend simple practical measures to achieve sustainable BP control among hypertensive patients with DM and CKD to minimize the VVV and improve their cardiovascular outcome.

Association of Visit-to-Visit Variability of Blood Pressure with Cardiovascular Disease among Type 2 Diabetes Mellitus Patients: A Cohort Study

BACKGROUND

Increasing evidence has shown that visit-to-visit variability (VVV) of blood pressure (BP) is associated with an increased risk of cardiovascular disease (CVD). The objective of this study was to evaluate the impact of VVV of systolic blood pressure (SBP) and diastolic blood pressure (DBP) on the risk of CVD among patients with type 2 diabetes mellitus (T2DM) in China.

METHODS

We conducted a retrospective cohort study of 10,163 T2DM patients who were not previously diagnosed with CVD from January 2008 to December 2012 in Ningbo, China. The VVV of BP was calculated using five metrics, including standard deviation (SD), coefficient of variation (CV), variation independent of mean, average real variability, and successive variability (SV) of measurements, obtained over a 24-month measurement period. Hazard ratios and 95% confidence intervals (CIs) were estimated by Cox proportional hazards regression models for the associations of variability in BP with risk of CVD.

RESULTS

A total of 894 CVD events were observed during a median follow-up of 49.5 months. The hazard ratio in the highest quintile of SD of SBP was 1.24 (95% CI, 1.01 to 1.52) compared with patients in the lowest quintile. The association between higher VVV of DBP and risk of CVD was not consistent across different metrics and sensitivity analyses.

CONCLUSION

Higher VVV of SBP was associated with an increased risk of CVD, irrespective of the mean SBP level. Future studies are needed to confirm these findings.

The relationship between visit-to-visit variability in blood pressure and incidence of metabolic syndrome: a general population-based cohort study in Korea

Background

Previous studies demonstrated that visit-to-visit variability of blood pressure (BP) has significant relationship with cardiovascular disease. Visit-to-visit variability in BP might have prognostic value for cardiovascular disease. The aim of this study is to evaluate the effect of visit-to-visit variability in BP on development of metabolic syndrome in general population without cardiovascular disease, diabetes mellitus, metabolic syndrome, and BP medication.

Method

We used data from the Korean Genome Epidemiology Study conducted by the Korean Centers for Disease Control and Prevention. All cohorts who were followed first 3 periods formed the basis of the study sample, which consisted of 7195 people. Of these samples, 3431 subjects who had cardiovascular disease, diabetes mellitus, or metabolic syndrome were excluded, and 312 subjects who were using antihypertensive medication in first 3 periods were excluded. Our final study sample consisted of 3452 cohorts.

Results

The mean age was 53.5 (8.25) years. The proportion of male was 50.2%. Average follow-up duration was 5.91 (0.17) years. In generalized estimating equation, the development of metabolic syndrome was associated with mean systolic BP (SBP) (Odd ratio (OR) 1.042, 95% confidence interval (CI) 1.035–1.048, p < 0.001), mean diastolic BP (DBP) (OR 1.058, 95% CI 1.049–1.069, p < 0.001), standard deviation (SD) of SBP (OR 1.036, 95% CI 1.017–1.055, p < 0.001), SD of DBP (OR 1.053, 95% CI 1.027–1.080, p < 0.001), and coefficient of variation (CV) of DBP (OR 1.025, 95% CI 1.005–1.046, p = 0.016) after adjusted for age, sex, and metabolic syndrome component. When mean SBP, mean DBP, SBP variability, and DBP variability were entered all together in the analysis model, SD of DBP (OR 1.033, 95% CI 1.003–1.063, p = 0.030) and CV of DBP (OR 1.027, 95% CI 1.004–1.051, p = 0.020) were significantly associated with the development of metabolic syndrome.

Conclusion

In general population without cardiovascular disease, diabetes mellitus, metabolic syndrome, and BP medication, SD of DBP and CV of DBP was associated with the development of metabolic syndrome. Visit-to-visit variability in DBP might be helpful for the prediction of future metabolic syndrome development.

Visit-to-visit systolic blood pressure variability in patients with ST-elevation myocardial infarction predicts long-term cardiovascular outcomes

Elevated visit-to-visit blood pressure variability (BPV), independent of mean BP, has been associated with cardiovascular events. However, its impact after ST-elevation myocardial infarction (STEMI) has not been established. This study aimed to investigate the prognostic impact of BPV on patients after STEMI. We analyzed the data and clinical outcomes of STEMI survivors who underwent successful primary coronary intervention from 2003 to 2009. BP was measured at discharge and at 1, 3, 6, 12, 24, and 36 months, and we calculated BPV as the intra-individual standard deviations (SDs) of systolic BP (SBP) across these measurements. We classified the patients as high and low-BPV group, and evaluated the outcomes: occurrence of major adverse cardiovascular events (MACEs), death, recurrent myocardial infarction, and target vessel revascularization within 60 months. We enrolled 343 patients, and mean follow-up duration was 68 ± 34 months (median: 76 months). Mean and median SBP SDs were 13.2 and 12.3 mmHg, and patients were divided into one of the two groups based on the median (high-BPV group = SD ≥ 12.3 mmHg; low-BPV group = SD < 12.3 mmHg). The MACE-free survival in the high-BPV group was significantly worse than that in low-BPV group (log-rank p = 0.035). For the high-BPV group, the risk of a MACE significantly increased by 57% (95% confidence interval: 1.03–2.39; p = 0.038). Visit-to-visit systolic BPV was associated with increased rates of adverse clinical outcomes in patients after STEMI. Careful assessment of BP and attempts to reduce BPV might be also important in STEMI survivors.

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.

Visit-to-visit blood pressure variability and future functional decline in old age

OBJECTIVE

Higher blood pressure variability (BPV), independent of mean blood pressure (BP), has been associated with adverse health outcomes. We investigated the association between visit-to-visit BPV and functional decline in older adults at high cardiovascular risk.

METHODS

In PROspective Study of Pravastatin in the Elderly at Risk, 4745 participants with mean age of 75.2 years and high cardiovascular risk were followed for a mean of 3.2 years. BP was measured in every 3 months during the first 18 months. BPV was defined as the intraindividual SD of measurements across these visits. Functional status in basic and instrumental activities of daily living was measured using the Barthel (ADL) and Lawton (IADL) scales, first at 18 months and then during follow-up until 48 months. Functional decline was calculated over this period.

RESULTS

BPV was not cross-sectionally associated with functional status at 18 months. Higher SBPV was associated with steeper functional decline, whereas DBPV was not. Each 10 mmHg higher SBPV was associated with a 0.064 (95% confidence interval 0.016-0.112, P = 0.009) annual decline in ADL score and with a 0.078 decline (95% confidence interval 0.020-0.136, P = 0.008) in IADL score. These associations were not modified by sex, hypertension or antihypertensives. These findings were independent of mean BP, cardiovascular risk factors and morbidities and cognition.

CONCLUSION

Higher visit-to-visit SBPV but not DBPV was associated with steeper functional decline in older adults at high cardiovascular risk. Higher SBPV is a novel risk factor for functional decline.

Hypertension and blood pressure variability management practices among physicians in Singapore

Purpose

There are limited data on blood pressure variability (BPV) in Singapore. The absence of updated local guidelines might contribute to variations in diagnosis, treatment and control of hypertension and BPV between physicians. This study evaluated BPV awareness, hypertension management and associated training needs in physicians from Singapore.

Materials and methods

Physicians from Singapore were surveyed between September 8, 2016, and October 5, 2016. Those included were in public or private practice for ≥3 years, cared directly for patients ≥70% of the time and treated ≥30 patients for hypertension each month. The questionnaire covered 6 main categories: general blood pressure (BP) management, BPV awareness/diagnosis, home BP monitoring (HBPM), ambulatory BP monitoring (ABPM), BPV management and associated training needs.

Results

Responses from 60 physicians (30 general practitioners [GPs], 20 cardiologists, 10 nephrologists) were analyzed (77% male, 85% aged 31–60 years, mean 22 years of practice). Approximately 63% of physicians considered white-coat hypertension as part of BPV. The most common diagnostic tool was HBPM (overall 77%, GPs 63%, cardiologists 65%, nephrologists 70%), but ABPM was rated as the tool most valued by physicians (80% overall), especially specialists (97%). Withdrawn Singapore guidelines were still being used by 73% of GPs. Approximately 48% of physicians surveyed did not adhere to the BP cutoff recommended by most guidelines for diagnosing hypertension using HBPM (>135/85 mmHg). Hypertension treatment practices also varied from available guideline recommendations, although physicians did tend to use a lower BP target for patients with diabetes or kidney disease. There were a number of challenges to estimating BPV, the most common of which was patient refusal of ABPM/HBPM. The majority of physicians (82%) had no training on BPV, but stated that this would be useful.

Conclusion

There appear to be gaps in knowledge and guideline adherence relating to the assessment and management of BPV among physicians in Singapore.

The association between changes in blood pressure components and incident cardiovascular diseases

PURPOSE

To determine the association of changes in blood pressure (BP) components between baseline examination (1999-2001) and a second visit (2002-2005) with incident cardiovascular diseases (CVD).

METHODS

In 3569 (2048 female) Iranian subjects ≥30 y, systolic BP, diastolic BP, mean arterial pressure (MAP) and pulse pressure (PP) were evaluated in two consecutive visits. Subjects were then followed for cardiovascular events. Multivariate sex-adjusted Cox Proportional-Hazards models were built for each BP component's change, and further adjusted for baseline BP values, traditional cardiovascular risk factors, and their changes.

RESULTS

During a median follow-up of 6.09 years after the second examination, 303 CVD cases occurred. A 1 SD increase in systolic BP, diastolic BP and MAP were significantly associated with 21%, 22%, and 95% increased CVD risk after adjustments for baseline values of BP components and other common risk factors (all p-values <0.05). Importantly, diastolic BP change resisted after further adjustment with systolic BP change (hazard ratio 1.21, CI 95% 1.05-1.39). PP change showed no significant association with CVD.

CONCLUSIONS

In a middle-aged population, three-year rises in systolic BP, diastolic BP, MAP, but not PP were associated with increased incident CVD. The significant association between diastolic BP change and CVD was shown independent of systolic BP change.

Visit-to-Visit Blood Pressure Variability and Mortality and Cardiovascular Outcomes Among Older Adults: The Health, Aging, and Body Composition Study

BACKGROUND

Level of blood pressure (BP) is strongly associated with cardiovascular (CV) events and mortality. However, it is questionable whether mean BP can fully capture BP-related vascular risk. Increasing attention has been given to the value of visit-to-visit BP variability.

METHODS

We examined the association of visit-to-visit BP variability with mortality, incident myocardial infarction (MI), and incident stroke among 1,877 well-functioning elders in the Health, Aging, and Body Composition Study. We defined visit-to-visit diastolic BP (DBP) and systolic BP (SBP) variability as the root-mean-square error of person-specific linear regression of BP as a function of time. Alternatively, we counted the number of considerable BP increases and decreases (separately; 10mm Hg for DBP and 20mm Hg for SBP) between consecutive visits for each individual.

RESULTS

Over an average follow-up of 8.5 years, 623 deaths (207 from CV disease), 153 MIs, and 156 strokes occurred. The median visit-to-visit DBP and SBP variability was 4.96 mmHg and 8.53 mmHg, respectively. After multivariable adjustment, visit-to-visit DBP variability was related to higher all-cause (hazard ratio (HR) = 1.18 per 1 SD, 95% confidence interval (CI) = 1.01-1.37) and CV mortality (HR = 1.35, 95% CI = 1.05-1.73). Additionally, individuals having more considerable decreases of DBP (≥10mm Hg between 2 consecutive visits) had higher risk of all-cause (HR = 1.13, 95% CI = 0.99-1.28) and CV mortality (HR = 1.30, 95% CI = 1.05-1.61); considerable increases of SBP (≥20mm Hg) were associated with higher risk of all-cause (HR = 1.18, 95% CI = 1.03-1.36) and CV mortality (HR = 1.37, 95% CI = 1.08-1.74).

CONCLUSIONS

Visit-to-visit DBP variability and considerable changes in DBP and SBP were risk factors for mortality in the elderly.

Which psychological, psychophysiological, and anthropometric factors are connected with life events, depression, and quality of life in patients with cardiovascular disease

OBJECTIVE

The aim of the study was to determine psychological, psychophysiological, and anthropometric factors connected with life events, level of depression, and quality of life in people at risk for cardiovascular disease and healthy controls.

METHODS

This is a cross-sectional study involving arterial hypertension patients and healthy controls. There were several measurements including physical, anthropological, cardiovascular, and psychophysiological measurements and administration of questionnaires.

RESULTS

A total of 99 participants were recruited for this study, 54 healthy controls (mean age: 35.59±13.39 years) and 45 patients with cardiovascular disease (CVD) (mean age: 46.33±12.39 years). The healthy controls and the patients with CVD significantly differed in the mean total score of life events, level of depression, quality of life score, temperature, blood pressure (BP), pulse transit time, heart rate, high-frequency total power, heart rate variability total power, waist-to-height ratio (WHtR), body fat percentage, fat control, pulse wave velocity, and augmentation index. In healthy subjects, the total score of the life events was not correlated with any cardiovascular or anthropometric factor. A score of depression significantly correlated with the WHtR, augmentation index, body fat percentage, and fat control. The quality of life - visual scale correlated with the body temperature, BP, and percentage of body fat. In the group of the patients with CVD, the score of the life events did not correlate with any measured cardiovascular or anthropometric factor. The level of depression correlated with the augmentation index. The quality of life - visual scale significantly correlated with body temperature, WHtR, and fat control.

CONCLUSION

The patients with CVD reported higher scores of life events, worse quality of life, and a greater level of depressive symptoms than healthy controls. In healthy controls, a higher mean total score of life events significantly negatively correlated with high-frequency total power, and the degree of depression correlated with being overweight. In patients with CVD, a score of depression was linked to being overweight.

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.

Importance of sustained and "tight" blood pressure control in patients with high cardiovascular risk

A retrospective further analysis of the ACTION database evaluated the relationship between cardiovascular outcomes and the "quality" of the control of blood pressure (BP). The study population (n = 6287) comprised those patients with four BP measurements during year 1 subdivided according to the proportion of visits in which BP was controlled in relation to two BP targets: < 140/90mmHg and < 130/80 mmHg. Differences between the BP control groups for the major prespecified ACTION outcomes were investigated with Cox proportional hazards models. For all the prespecified cardiovascular endpoints the incidence declined as the proportion of visits with BP control increased. The greatest differences in outcomes between the different BP control groups were observed for the risk of stroke but were still apparent for all the other endpoints. For example, the risks for the primary outcome [hazard ratio (HR) 0.78; 95% confidence interval (CI) 0.67 to 0.90] were significantly less in the group with >_75% of visits with BP control than in the group with < 25% of visits with BP control. There were no significant treatment-related differences. Retrospective analyses are not definitive but these results highlight the importance of the attainment of BP control targets and the consistency of BP control during long-term follow-up.

Higher visit-to-visit intra-dialytic blood pressure is associated with the progression of aortic valve stenosis in chronic hemodialysis patients

Aortic valve stenosis (AS) is a frequent complication contributing to poor prognosis in chronic hemodialysis (CHD) patients. High blood pressure (BP) is known to be associated with AS progression in the general population. In CHD patients, however, BP varies during and between hemodialysis sessions with ultrafiltration volume or inter-dialytic weight gain; therefore it is difficult to characterize the BP status with a conventional single measurement. Our purpose was to clarify the BP variables affecting AS progression in CHD patients. We retrospectively enrolled 32 consecutive CHD patients with AS [aortic valve area (AVA), 1.3 ± 0.3 cm(2); mean age 69 ± 8 years] who had serial transthoracic echocardiographic studies at least 6 months apart (mean 23 ± 9 months). AS progression was evaluated using absolute reduction in AVA per year. Pre-dialytic and intra-dialytic (every hour during sessions) BPs throughout the 3 consecutive visits were used to determine each patient's BP status. We calculated the mean values of pre-dialytic and intra-dialytic BPs and their variability. In univariate analysis, mean visit-to-visit pre-dialytic and intra-dialytic BP were associated with AS progression, whereas all variables of BP variability were not. Multiple regression analysis indicated that only mean visit-to-visit intra-dialytic systolic and diastolic BP remained independently associated with AS progression after adjustment for age, sex, hypertension, hypercholesterolemia, diabetes mellitus, and serum parathyroid hormone (p < 0.05). Although BP regulation in CHD patients is complex and multifactorial, mean visit-to-visit intra-dialytic BP was independently associated with AS progression. Prospective studies are necessary before considering intra-dialytic BP as a potential target for therapy.

Heterogeneity of prognostic studies of 24-hour blood pressure variability: systematic review and meta-analysis

In addition to mean blood pressure, blood pressure variability is hypothesized to have important prognostic value in evaluating cardiovascular risk. We aimed to assess the prognostic value of blood pressure variability within 24 hours. Using MEDLINE, EMBASE and Cochrane Library to April 2013, we conducted a systematic review of prospective studies of adults, with at least one year follow-up and any day, night or 24-hour blood pressure variability measure as a predictor of one or more of the following outcomes: all-cause mortality, cardiovascular mortality, all cardiovascular events, stroke and coronary heart disease. We examined how blood pressure variability is defined and how its prognostic use is reported. We analysed relative risks adjusted for covariates including the appropriate mean blood pressure and considered the potential for meta-analysis. Our analysis of methods included 24 studies and analysis of predictions included 16 studies. There were 36 different measures of blood pressure variability and 13 definitions of night- and day-time periods. Median follow-up was 5.5 years (interquartile range 4.2–7.0). Comparing measures of dispersion, coefficient of variation was less well researched than standard deviation. Night dipping based on percentage change was the most researched measure and the only measure for which data could be meaningfully pooled. Night dipping or lower night-time blood pressure was associated with lower risk of cardiovascular events. The interpretation and use in clinical practice of 24-hour blood pressure variability, as an important prognostic indicator of cardiovascular events, is hampered by insufficient evidence and divergent methodologies. We recommend greater standardisation of methods.

Biological correlates of blood pressure variability in elderly at high risk of cardiovascular disease

BACKGROUND

Visit-to-visit variability in blood pressure is an independent predictor of cardiovascular disease. This study investigates biological correlates of intra-individual variability in blood pressure in older persons.

METHODS

Nested observational study within the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) among 3,794 male and female participants (range 70-82 years) with a history of, or risk factors for cardiovascular disease. Individual visit-to-visit variability in systolic and diastolic blood pressure and pulse pressure (expressed as 1 SD in mm Hg) was assessed using nine measurements over 2 years. Correlates of higher visit-to-visit variability were examined at baseline, including markers of inflammation, endothelial function, renal function and glucose homeostasis.

RESULTS

Over the first 2 years, the mean intra-individual variability (1 SD) was 14.4mm Hg for systolic blood pressure, 7.7mm Hg for diastolic blood pressure, and 12.6mm Hg for pulse pressure. After multivariate adjustment a higher level of interleukin-6 at baseline was consistently associated with higher intra-individual variability of blood pressure, including systolic, diastolic, and pulse pressure. Markers of endothelial function (Von Willebrand factor, tissue plasminogen activator), renal function (glomerular filtration rate) and glucose homeostasis (blood glucose, homeostatic model assessment index) were not or to a minor extent associated with blood pressure variability.

CONCLUSION

In an elderly population at risk of cardiovascular disease, inflammation (as evidenced by higher levels of interleukin-6) is associated with higher intra-individual variability in systolic, diastolic, and pulse pressure.

The effects of weight loss and salt reduction on visit-to-visit blood pressure variability: results from a multicenter randomized controlled trial

OBJECTIVES

As evidence suggests visit-to-visit variability (VVV) of blood pressure (BP) is associated with cardiovascular events and mortality, there is increasing interest in identifying interventions that reduce VVV of BP. We investigated the effects of weight loss and sodium reduction, alone or in combination, on VVV of BP in participants enrolled in phase II of the Trials of Hypertension Prevention.

METHODS

BP readings were taken at 6-month intervals for 36 months in 1820 participants with high-normal DBP who were randomized to weight loss, sodium reduction, combination (weight loss and sodium reduction), or usual care groups. VVV of BP was defined as the SD of BP across six follow-up visits.

RESULTS

VVV of SBP was not significantly different between participants randomized to the weight loss (7.2 ± 3.1  mmHg), sodium reduction (7.1 ± 3.0  mmHg), or combined (6.9 ± 2.9  mmHg) intervention groups vs. the usual care group (6.9 ± 2.9  mmHg). In a fully adjusted model, no difference (0.0 ± 0.2  mmHg) in VVV of SBP was present between individuals who successfully maintained their weight loss vs. individuals who did not lose weight during follow-up (P = 0.93). Also, those who maintained a reduced sodium intake throughout follow-up did not have lower VVV of SBP compared to those who did not reduce their sodium intake (0.1 ± 0.3  mmHg; P = 0.77). Results were similar for VVV of DBP.

CONCLUSIONS

These findings suggest that weight loss and sodium reduction may not be effective interventions for lowering VVV of BP in individuals with high-normal DBP.

The prognostic value of long-term visit-to-visit blood pressure variability on stroke in real-world practice: a dynamic cohort study in a large representative sample of Chinese hypertensive population

BACKGROUND

The prognostic significance of long-term visit-to-visit blood pressure variability (BPV) has not yet been validated in "real world" hypertensive patients. The aim of the current study is to explore the prognostic value of BPV on stroke in hypertensive patients.

METHODS

This was a dynamic prospective cohort study based on electronic medical records in Shanghai, China. Hypertensive patients (N=122,636) without history of stroke at baseline, were followed up from 2005 to 2011. The cohort comprised of 4522 stroke patients and 118,114 non-stroke patients during a mean follow-up duration of 48 months. BPV was measured by standard deviation (SD) and the coefficient of variation (CV) of blood pressure.

RESULTS

The visit-to-visit variability of both systolic blood pressure (SBP) and diastolic blood pressure (DBP) was independently associated with the occurrence of stroke [SD: the hazard ratios (95% confidence intervals) of SBP and DBP were 1.042 (1.021 to 1.064) and 1.052 (1.040 to 1.065); CV: the hazard ratios (95% confidence intervals) of SBP and DBP were 1.183 (1.010 to 1.356) and 1.151 (1.005 to 1.317), respectively]. The hazard ratio values increased along with an increase of the BPV levels of SBP and DBP. The increment effect remained significant after controlling the blood pressure control status of subjects.

CONCLUSIONS

Increased BPV of both SBP and DBP, independent of the average blood pressure, is a predictor of stroke among community hypertensive patients in real-world clinical practice. The risk of stroke increased along with increased BPV. Stabilizing BPV might be a therapeutic target in hypertension.

Randomised double-blind comparison of placebo and active drugs for effects on risks associated with blood pressure variability in the Systolic Hypertension in Europe trial

Background

In the Systolic Hypertension in Europe trial (NCT02088450), we investigated whether systolic blood pressure variability determines prognosis over and beyond level.

Methods

Using a computerised random function and a double-blind design, we randomly allocated 4695 patients (≥60 years) with isolated systolic hypertension (160–219/<95 mm Hg) to active treatment or matching placebo. Active treatment consisted of nitrendipine (10–40 mg/day) with possible addition of enalapril (5–20 mg/day) and/or hydrochlorothiazide (12.5–25.0 mg/day). We assessed whether on-treatment systolic blood pressure level (SBP), visit-to-visit variability independent of the mean (VIM) or within-visit variability (WVV) predicted total (n = 286) or cardiovascular (n = 150) mortality or cardiovascular (n = 347), cerebrovascular (n = 133) or cardiac (n = 217) endpoints.

Findings

At 2 years, mean between-group differences were 10.5 mm Hg (p<0.0001) for SBP, 0.29 units (p = 0.20) for VIM, and 0.07 mm Hg (p = 0.47) for WVV. Active treatment reduced (p≤0.048) cardiovascular (−28%), cerebrovascular (−40%) and cardiac (−24%) endpoints. In analyses dichotomised by the median, patients with low vs. high VIM had similar event rates (p≥0.14). Low vs. high WVV was not associated with event rates (p≥0.095), except for total and cardiovascular mortality on active treatment, which were higher with low WVV (p≤0.0003). In multivariable-adjusted Cox models, SBP predicted all endpoints (p≤0.0043), whereas VIM did not predict any (p≥0.058). Except for an inverse association with total mortality (p = 0.042), WVV was not predictive (p≥0.15). Sensitivity analyses, from which we excluded blood pressure readings within 6 months after randomisation, 6 months prior to an event or both were confirmatory.

Conclusions

The double-blind placebo-controlled Syst-Eur trial demonstrated that blood-pressure lowering treatment reduces cardiovascular complications by decreasing level but not variability of SBP. Higher blood pressure level, but not higher variability, predicted risk.

Trial Registration

ClinicalTrials.gov NCT02088450

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.

Redefined blood pressure variability measure and its association with mortality in elderly primary care patients

Visit-to-visit blood pressure (BP) variability has received considerable attention recently. The objective of our study is to define a variability measure that is independent of change over time and determine the association between longitudinal summary measures of BP measurements and mortality risk. Data for the study came from a prospective cohort of 2906 adults, aged ≥60 years, in an urban primary care system with ≤15 years of follow-up. Dates of death for deceased participants were retrieved from the National Death Index. Systolic and diastolic BP measurements from outpatient clinic visits were extracted from the Regenstrief Medical Record System. For each patient, the intercept, regression slope, and root mean square error for visit-to-visit variability were derived using linear regression models and used as independent variables in Cox proportional hazards models for both all-cause mortality and mortality attributable to coronary heart disease or stroke. Rate of change was associated with mortality risk in a U-shaped relationship and that participants with little or no change in BP had the lowest mortality risk. BP variability was not an independent predictor of mortality risk. By separating change over time from visit-to-visit variability in studies with relatively long follow-up, we demonstrated in this elderly primary care patient population that BP changes over time, not variability, were associated with greater mortality risk. Future research is needed to confirm our findings in other populations.

Visit-to-visit blood pressure variability, silent cerebral injury, and risk of stroke

Apart from the well-known role of hypertension in cerebrovascular disease, visit-to-visit blood pressure (BP) variability is emerging as an independent risk factor for stroke. Although the underlying mechanism is not fully understood, artery remodeling is thought to be closely involved in the relationship between visit-to-visit BP variability and stroke. This review article summarizes the recent literature on these topics. Silent cerebral injury is considered to serve as a common pathophysiology in the relationship of visit-to-visit BP variability with cognitive impairment and stroke. Here we review visit-to-visit BP variability, some comparisons of the effects of antihypertensive agents on visit-to-visit BP variability, and an issue regarding the impact of these agents on stroke.

Blood pressure variability and the risk of all-cause mortality, incident myocardial infarction, and incident stroke in the cardiovascular health study

BACKGROUND

Recent reports have linked variability in visit-to-visit systolic blood pressure (SBP) to risk of mortality and stroke, independent of the effect of mean SBP level. This study aimed to evaluate whether variability in SBP is associated with all-cause mortality, incident myocardial infarction (MI), and incident stroke, independent of mean SBP or trends in SBP levels over time.

METHODS

The Cardiovascular Health Study is a longitudinal cohort study of vascular risk factors and disease in the elderly. Participants who attended their first 5 annual clinic visits and experienced no event before the 5th visit were eligible (n = 3,852). Primary analyses were restricted to participants not using antihypertensive medications throughout the first 5 clinic visits (n = 1,642). Intraindividual SBP variables were defined using each participant's 5-visit blood pressure measures. Cox proportional hazards models estimated adjusted hazard ratios (HRs) per SD increase in intraindividual SBP variability, adjusted for intraindividual SBP mean and change over time.

RESULTS

Over a mean follow-up of 9.9 years, there were 844 deaths, 203 MIs, and 195 strokes. Intraindividual SBP variability was significantly associated with increased risk of mortality (HR = 1.13; 95% confidence interval (CI) = 1.05-1.21) and of incident MI (HR = 1.20; 95%CI = 1.06-1.36), independent of the effect from adjustment factors. Intraindividual SBP variability was not associated with risk of stroke (HR = 1.03; 95% CI = 0.89-1.21).

CONCLUSIONS

Long-term visit-to-visit SBP variability was independently associated with a higher risk of subsequent mortality and MI but not stroke. More research is needed to determine the relationship of BP variability with cardiovascular risk and the clinical implications.

The speed of blood pressure fluctuations in patients with chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) has been associated with increased risk for cardiovascular disease but mechanisms underlying this association are incompletely understood. The speed of beat-to-beat changes in systolic blood pressure (vSBP) was found to be pronounced in patients with elevated cardiovascular risk. Although increased vSBP may thus be a contributing mechanism to cardiovascular morbidity, no data exist on vSBP in patients with COPD. Therefore, the purpose of this study was to evaluate whether there is an association between severity of COPD and vSBP.

METHODS

Resting beat-to-beat blood pressure was recorded during 5 min. vSBP was assessed by calculating the slopes of oscillatory fluctuations in SBP for different inter-beat intervals (IBI). Univariate and multivariate analyses were performed to evaluate the association between forced expiratory volume in 1 s (FEV1) and vSBP.

RESULTS

This study comprised 60 patients with COPD (24 females) with a mean [SD] FEV1 of 45.4 [22.7] %predicted and 34 healthy controls. Short-term fluctuations in SBP were more pronounced in patients with COPD compared to healthy controls. There was a significant inverse correlation between FEV1 and vSBP (r=-0.41, p=0.001). Even after adjustment for covariates in multivariate analysis, FEV1 was found to be independently associated with vSBP.

CONCLUSIONS

Patients with COPD are characterised by steeper blood pressure changes than healthy controls. The speed of fluctuations in SBP is associated with the severity of airflow limitation. Increased vSBP may be a mechanism underpinning the association between COPD and cardiovascular disease.

Long-term and ultra long-term blood pressure variability during follow-up and mortality in 14,522 patients with hypertension

Recent evidence indicates that long-term visit-to-visit blood pressure variability (BPV) may be an independent cardiovascular risk predictor. The implication of this variability in hypertension clinical practice is unclear. BPV as average real variability (ARV) was calculated in 14,522 treated patients with hypertension in 4 time frames: year 1 (Y1), years 2 to 5 (Y2-5), years 5 to 10 (Y5-10), and years >10 (Y10+) from first clinic visit. Cox proportional hazards models for cause-specific mortality were used in each time frame separately for long-term BPV, across time frames based on ultra long-term BPV, and within each time frame stratified by mean BP. ARV in systolic blood pressure (SBP), termed ARV(SBP), was higher in Y1 (21.3±11.9 mm Hg) in contrast to Y2-5 (17.7±9.9 mm Hg), Y5-10 (17.4±9.6 mm Hg), and Y10+ (16.8±8.5 mm Hg). In all time frames, ARV(SBP) was higher in women (P<0.01) and in older age (P<0.001), chronic kidney disease (P<0.01), and prevalent cardiovascular disease (P<0.01). Higher long-term and ultra long-term BPV values were associated with increased mortality (all-cause, cardiovascular, and noncardiovascular mortality; P for trend, <0.001). This relationship was also evident in subgroups with mean SBP<140 mm Hg in all time frames. Monitoring BPV in clinical practice may facilitate risk reduction strategies by identifying treated hypertensive individuals at high risk, especially those with BP within the normal range.

Associations of aortic distensibility and arterial elasticity with long-term visit-to-visit blood pressure variability: the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Although higher visit-to-visit variability (VVV) of blood pressure (BP) is associated with increased cardiovascular disease risk, the physiological basis for VVV of BP is incompletely understood.

METHODS

We examined the associations of aortic distensibility (assessed by magnetic resonance imaging) and artery elasticity indices (determined by radial artery pulse contour analysis) with VVV of BP in 2,640 and 4,560 participants, respectively, from the Multi-Ethnic Study of Atherosclerosis. Arterial measures were obtained at exam 1. BP readings were taken at exam 1 and at 3 follow-up visits at 18-month intervals (exams 2, 3, and 4). VVV was defined as the SD about each participant's mean systolic BP (SBP) across visits.

RESULTS

The mean SDs of SBP were inversely associated with aortic distensibility: 7.7, 9.9, 10.9, and 13.2mm Hg for quartiles 4, 3, 2, and 1 of aortic distensibility, respectively (P trend < 0.001). This association remained significant after adjustment for demographics, cardiovascular risk factors, mean SBP, and antihypertensive medication use (P trend < 0.01). In a fully adjusted model, lower quartiles of large artery and small artery elasticity (LAE and SAE) indices were also associated with higher mean SD of SBP (P trend = 0.02 for LAE; P trend < 0.001 for SAE).

CONCLUSIONS

In this multiethnic cohort, functional alterations of central and peripheral arteries were associated with greater long-term VVV of SBP.

Quantifying the speed of fluctuations in systolic blood pressure

Increased blood pressure variability (BPV), even in the absence of hypertension, has been identified as an important independent cardiovascular risk factor (CVRF). However, the role of the speed of changes in systolic blood pressure (SBP; vSBP) on cardiovascular risk needs to be investigated. The objective of this study was to investigate whether subjects with a high cardiovascular risk profile have an increased degree and speed of changes in SBP compared with subjects with low or no risk. Resting beat-to-beat blood pressure (BP) was recorded for 5 min. Standard BPV measures in both time and frequency domains were conducted. The s.d. of SBP (s.d.-SBP) values was used to quantify the degree of BPV. vSBP was assessed by calculating the slopes of oscillatory fluctuations in SBP for different interbeat intervals (IBI). Subjects were allocated to one of four groups according to the number of CVRFs (0, 1, 2, ≥ 3 CVRF). Of 122 subjects, 19.7% had 0 CVRF, 27.0% had 1, 32.0% had 2 and 21.3% had ≥ 3 CVRFs. There was an increase in vSBP across the four risk groups. The vSBP in patients without CVRF was 3.12 (1.09), 1 CVRF 3.23 (1.07), 2 CVRF 4.16 (2.26) and ≥ 3 CVRF 4.22 (1.66; P = 0.015). The s.d.-SBP was not significantly different between the cardiovascular risk groups. The speed of fluctuations in SBP rather than the degree of BPV is pronounced in patients with elevated cardiovascular risk. Increased speed of BP fluctuations may thus be a contributing mechanism to cardiovascular morbidity.