Visit-to-visit Variability Of Blood Pressure Research Articles

The Association between Visit-to-Visit Variability of Blood Pressure and the Risk of Metabolic Syndrome: The Moderating Effect of Weight

Aims. Metabolic syndrome (MetS) affects approximately one-third of the global population. Visit-to-visit variability of blood pressure (VVV-BP) constitutes a substantial risk factor for numerous chronic conditions. Thus, this study aimed to assess the relationship between VVV-BP and MetS and identify potential moderating factors between these. Methods. Data were obtained from the China Health and Retirement Longitudinal Study, a nationally representative study. Multiple logistic regression analyses were utilized to explore the association between VVV-BP and MetS while incorporating moderation analyses. MetS was defined according to the criteria outlined in the Joint Interim Statement. VVV-BP was expressed by the standard deviation, coefficient of variation, average real variability, and root mean square error. Results. Individuals with the highest levels of VVV of systolic blood pressure (SBP) exhibited a 70% increased risk of MetS compared to those with the lowest levels (OR = 1.70, 95% CI = 1.31–2.21). In addition, they had a 41% increased risk of VVV of diastolic blood pressure (DBP) (OR = 1.41, 95% CI = 1.09–1.81). Notably, weight change status significantly influenced the relationship between VVV-BP and MetS (Pinteraction = 0.01). Conclusions. VVV-BP is a significant contributor to the risk of developing MetS. Importantly, individuals who experienced weight loss during the follow-up period did not face a significantly higher risk of developing MetS.

PS-C12-2: VISIT-TO-VISIT BLOOD PRESSURE VARIABILITY AND CLINICAL EVENTS IN OLDER PATIENTS RECEIVING HOME MEDICAL CARE: THE OHCARE STUDY

Aim: We investigated the associations of visit-to-visit variability(VVV) of blood pressure (BP) with clinical events (death, hospitalization, falling) in older patient around 85 years old receiving home medical care. Methods: This study was performed in OHCARE (Osaka Home CAre REgistry), which is a prospective cohort study targeted old patients receiving home-based medical care in Japan. There were 103 eligible patients fulfilling the inclusion criteria: aged 65 years or older; BP measurements at least three occasions before the baseline date (median 4.78 occasions); BP measurement interval in 16 ± 13 days (median ± 1SD). We used the standard deviation (SD), Coefficient of variation (CV) of SBP measured at baseline as the VVV of BP. Main outcomes were clinical events including hospitalizations, falling and death during follow-up period. Results: It was clarified that VVV of BP was exists in older patients receiving home medical care (10.7 / 7.2 mmHg). Regarding the relationship between VVV and clinical events during follow-up, the rate of hospitalization was significantly higher in the group with the largest SBP-SD than in the group with the smallest. Furthermore, multivariate analysis adjusted by age, sex, ADL and current diseases showed that SD and CV of SBP were independent positive association of hospitalization events. Conclusion: In older patients with frailty requiring home medical care, a higher VVV in SBP may be related to the occurrence of events leading hospitalizations. Furthermore, higher VVV in SBP could be a predictive marker of clinical events leading to hospitalization.

Visit-to-visit variability in blood pressure and kidney disease progression in IgA nephropathy.

The visit-to-visit variability (VVV) in blood pressure (BP) is an important risk factor for stroke and coronary heart disease and may also be associated with kidney damage and the development of chronic kidney disease (CKD). Data on the association between VVV in BP and the risk of CKD progression among patients with immunoglobulin A nephropathy (IgAN) are limited. We aimed to evaluate the relationships of VVV in BP with the progression of IgAN. We assessed 1376 patients with IgAN at Peking University First Hospital. The main VVV in BP was expressed as the standard deviation (SD), coefficient of variation (CV) and average real variability (ARV). The associations of variability in BP with composite kidney disease progression events, defined as a 50% decline in estimated glomerular filtration rate (eGFR) and kidney failure, were examined using Cox models. During a median follow-up of 44.1months (interquartile range 23.0-76.7), 247 (18.0%) patients experienced composite kidney disease progression events. With a higher SD in systolic BP (SBP) values, the risk of kidney disease progression events increased {hazard ratio [HR] 1.07 [95% confidence interval (CI) 1.03-1.11]; P<.001} after maximal adjustment, including baseline SBP and mean SBP during the first 12-month period. Using the first quartile of SD SBP values as the reference, the risk of composite kidney disease progression events was higher among patients with higher SD SBP values; the HR was 2.12 (95% CI 1.31-3.44) in the highest quartile (P for trend<.001). A similar trend could be observed when analysing the SD of diastolic BP, but the risk was not significantly increased. The associations were similar when analysed with the CV and ARV. SBP variability was significantly associated with kidney disease progression in IgAN.

Impact of visit-to-visit blood pressure variability on hypertensive-mediated target organ damage and future cardiovascular events: the Campania salute network.

Exaggerated variability of blood pressure (BP) poses additional stress on cardiovascular system independent of BP average value, increasing risk of target organ damage (HMOD) and cardiovascular events. We assessed the impact of visit-to-visit variability (VVV) of BP on development of cardiovascular events and HMOD. Standard deviation (SD) and coefficient of variability of mean SBP and DBP were calculated in 3555 patients from the Campania Salute Network registry, with available echocardiogram and more than six visits during follow-up. Values from the first visit were excluded. The impact of VVV of BP on cardiovascular events, and mediation of HMOD were assessed at final visit. Mean number of visits was 11 ± 6 with mean interval between visits of 9.1 ± 3.7 months. Mean visit-to-visit SD during follow-up was 13 ± 5 for systolic and 8 ± 3 mmHg for DBP; coefficients of variability were 9.7 ± 3.5 and of 9.6 ± 3.2, respectively. In multivariable analysis, left ventricular mass at follow-up was correlated with systolic VVV of BP independently of significant effect of age, BMI, mean SBP during follow-up and initial left ventricular mass. Follow-up GFR was inversely associated with systolic and diastolic VVV, independently of significant effect of age, mean glucose and SBP during follow-up, and initial GFR. In Cox regression, high VVV of BP was also associated with increased risk of cardiovascular events (hazard ratio 1.49, 95% confidence interval 1.08-2.06, P = 0.015), independently of significant effect of HMOD. VVV is associated with prevalent HMOD and development of cardiovascular events, independently of mean BP value during follow-up and HMOD.

Visit-to-visit blood pressure variability is associated with arterial stiffness in Chinese adults: A prospective analysis.

Blood pressure (BP) variability may have its effect on the development of vascular disease. The authors aimed to examine the association between the visit‐to‐visit variability (VVV) of BP and arterial stiffness in Chinese adults. The authors included 1407 participants from a prospective cohort study of community residents who were ≥40 years, without a history of myocardial infarction or stroke, and with data at the baseline, the second and the third visits in 2008, 2009, and 2013. The VVV of BP was defined as the standard deviation (SD), the coefficient of variation (CV), the average successive variability (ASV), and the variability independent of the mean (VIM) in BP levels at the 3 visits. Arterial stiffness was measured by brachial‐ankle pulse wave velocity (ba‐PWV) at the 2nd and the 3rd visits. Levels of ba‐PWV change and the occurrence of an elevated ba‐PWV increased significantly in the highest tertile of VVV measures of systolic BP (SBP) and pulse pressure (PP) compared with the lowest tertile, respectively. The multivariable regression analysis revealed that VVV measures of SBP and PP were significantly associated with levels of ba‐PWV change and the risks of developing an elevated ba‐PWV. The odds ratios (ORs) and 95% confidence intervals (CIs) for the risk were 2.12 (1.57–3.12) and 1.92 (1.38–2.68) in participants with the highest versus the lowest tertile of SBP‐SD and PP‐SD, respectively. No significant association was found for diastolic BP variability measures. The increased long‐term variabilities of SBP and PP were associated with an increased risk of arterial stiffness.

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

ABSTRACT 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.

Association of visit-to-visit variability in blood pressure and first stroke risk in hypertensive patients with chronic kidney disease.

Data on the association between visit-to-visit variability (VVV) in blood pressure (BP) and the risk of stroke among hypertensive patients with chronic kidney disease (CKD) is limited. We aimed to evaluate the relation of VVV in BP with the risk of stroke, and examine any possible effect modifiers in hypertensive patients with mild-to-moderate CKD. This is a post-hoc analysis of the China Stroke Primary Prevention Trial. A total of 3091 patients with estimated glomerular filtration rate 30-60 ml/min per 1.73 m and/or proteinuria at baseline, without occurring stroke and with BP measurements of at least two visits from randomization to the 12-month visit were included. The main VVV in BP was expressed as SD. The primary outcome was first stroke. The median subsequent treatment duration was 3.7 years. After multivariable adjustment, including baseline SBP and mean SBP during the first 12-month follow-up, there was a significantly positive relationship of SD SBP with the risk of subsequent first stroke (per SD increment; odds ratio, 1.41; 95% confidence interval: 1.17-1.69) and first ischemic stroke (odds ratio, 1.55; 95% confidence interval: 1.26-1.90). Results were consistent across various subgroups, including age, sex, baseline SBP, treatment compliance, and mean SBP, concomitant usage of calcium channel blocker during the first 12-month follow-up period. Similar trends were also found for coefficient of variation SBP, and SD or coefficient of variation DBP. However, there was no significant association between BP variability and first hemorrhagic stroke. In hypertensive adults with mild-to-moderate CKD, visit-to-visit variability in BP was significantly associated with the risk of subsequent first stroke.

1652-P: The Association between Long-Term HbA1c Variability, Blood Pressure, Cholesterol, and Body Weight in Type 2 Diabetes: Subanalysis of ABC Study

Aim: Visit-to-visit variability (VVV) of HbA1c was reported to be the risk of cardiovascular disease (CVD) in patients with type 2 diabetes mellitus (T2DM). However, factors related to VVV of HbA1c remain unclear. This study is first examined relationship between VVV of HbA1c and various parameters including VVV of blood pressure (BP), low-density lipoprotein-cholesterol (LDL-C), and body mass index (BMI). Material and Methods: Analyzed were 4,678 patients with T2DM throughout Japan (38 hospitals). The inclusion criteria were patients whose HbA1c, BP, LDL-C, and BMI were measured 12 or more times during the 24-month period. VVV of HbA1c, BP, LDL-C, and BMI were evaluated using the coefficient of variation (CV). This study is sub-analysis of ABC trial (UMIN000034231). Results: Mean age of participants was 61.3 ± 9.4 years (mean ± SD) and HbA1c was 57.2 ± 13.5 mmol/mol (7.4 ± 1.2%). Table shows univariate correlate and multiple regression analysis of HbA1c CV. HbA1c CV was correlated with HbA1c baseline, SBP CV, LDL-C CV, and BMI CV. In the multiple regression analysis, HbA1c baseline, LDL-C, and BMI CV were the strongest predictors of HbA1c CV. Conclusion: VVV of HbA1c was strongly correlated with VVV of LDL-C and BMI, and HbA1c baseline in patients with T2DM. A large-scale clinical trial needs to be conducted to clarify factors affecting VVV of HbA1c. Disclosure S. Minato: None. D. Matsutani: None. Y. Tsujimoto: None. Y. Kayama: None. M. Sakamoto: None. M. Nishikawa: None. K. Utsunomiya: None.

Visit-to-visit variability in blood pressure and the development of chronic kidney disease in treated general hypertensive patients.

Data on the association between visit-to-visit variability (VVV) in blood pressure (BP) and the risk of chronic kidney disease (CKD) in general treated hypertensive patients were limited. We aimed to evaluate the relation of VVV in BP with the development of CKD, and examine any possible effect modifiers in hypertensive patients without prior cardiovascular diseases (CVDs) or CKD. This is a post hoc analysis of the Renal Sub-study of the China Stroke Primary Prevention Trial (CSPPT). A total of 10051 hypertensives without CVD and CKD and with at least six visits of BP measurements from randomization to the 24-month visit were included. The main VVV in BP was expressed as standard deviation (SD). The primary outcome was the development of CKD, defined as a decrease in estimated glomerular filtration rate ≥30% and to a level of <60 mL/min/1.73 m2, or end-stage renal disease. The median treatment duration was 4.4 years. After multivariable adjustment, including baseline systolic blood pressure (SBP) and mean SBP during the first 2-year treatment period, there was a significantly positive relationship of SD of SBP with the risk of CKD development (per SD increment; odds ratio, 1.27; 95% confidence interval: 1.10-1.46). The results were similar for coefficient of variation (CV) of SBP. Results across various subgroups, including age, sex, SBP at baseline, treatment compliance, concomitant antihypertensive medications and mean SBP during the first 24-month treatment period, were consistent. SBP variability, irrespective of mean BP level, was significantly associated with the development of CKD in general treated hypertensive patients.

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

BackgroundIncreasing 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.MethodsWe 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.ResultsA 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.ConclusionHigher 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.

Significance of Cardiac Rehabilitation on Visit-to-Visit Variability of Blood Pressure in Patients With Cardiovascular Disease in a 12-Month Follow-Up

BackgroundVisit-to-visit variability (VVV) in blood pressure (BP) has been shown to be a strong predictor of cardiovascular disease (CVD). However, the long-term effect of comprehensive cardiac rehabilitation (CR) with exercise training on VVV in BP has not yet been established. Therefore, we evaluated the long-term effects of CR on VVV in BP in patients with CVD.MethodsTwenty-two CVD patients in a 12-month CR program who had at least six clinic visits per month to measure BP were enrolled. We determined VVV in BP expressed as the standard deviation of average BP every month for 12 months.ResultsThe mean age was 70 ± 8 years and the body mass index was 24.4 ± 4.9 kg/m2. In addition, the percentage (%) of males, % heart failure and % ischemic heart disease were 77%, 55% and 27%, respectively. Patients who had uncontrolled BP at baseline showed a significant reduction of both systolic BP (SBP) and diastolic BP (DBP). VVV in SBP in the first month was significantly less than that in the last month, although there was no difference in VVV in DBP. Patients were divided into larger (L-) and smaller (S-) VVV in SBP groups according to the average value of VVV in SBP as a cut-off. The L-VVV in SBP group, but not the S-VVV in SBP group, showed a significant reduction of VVV in SBP.ConclusionComprehensive CR may improve VVV in SBP in CVD patients who have larger VVV in SBP.

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

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. 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. 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). 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 Variability and Reduction in Blood Pressure After a 3-Month Cardiac Rehabilitation Program in Patients With Cardiovascular Disease.

Visit-to-visit variability (VVV) in blood pressure (BP) has been shown to be a predictor of cardiovascular events. It is unknown whether CR can improve VVV in BP as well as reducing BP. We enrolled 84 patients who had cardiovascular disease (CVD) and participated in a 3-month CR program. We measured systolic and diastolic BP (SBP and DBP), pulse pressure (PP), and heart rate (HR) before exercise training at each visit and determined VVV in BP or HR expressed as the standard deviation of the average BP or HR. Patients who had uncontrolled BP at baseline and who did not change their antihypertensive drugs throughout the study period showed a significant reduction of both SBP and DBP with a decrease in PP after 3 months. Patients who did not change their antihypertensive drugs were divided into larger (L-) and smaller (S-) VVV in the SBP groups and L- and S-VVV in the DBP groups according to the average value of VVV in SBP or DBP. In the L-VVV in the SBP and DBP groups, VVV in SBP and DBP in the 1st month was significantly decreased after the 3rd month in both groups. HR at baseline was significantly decreased after 3 months. In addition, CR induced a significant increase in the level of high-density lipoprotein cholesterol (HDL-C) in blood. In conclusion, CR improved VVV in BP in patients with L-VVV in BP and evoked a significant reduction in HR and an increase in HDL-C. These effects due to the CR program may be cardioprotective.

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

Variability of blood pressure (BP) across outpatient visits is frequently dismissed as random fluctuation around a patient's underlying BP. To examine the association of visit-to-visit variability (VVV) of systolic BP (SBP) and diastolic BP with cardiovascular disease (CVD) and mortality outcomes. Prospective cohort study. Post hoc analysis of ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial). 25814 ALLHAT participants. 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. 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. Long-term outcomes were not available. 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. National Institutes of Health.

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

BackgroundVisit-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).MethodsWe 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.ResultsThere 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.ConclusionHigher VVV in SBP and maximum SBP in patients with ACS after successful PCI were associated with the onset of MI.

The effects of weight loss and salt reduction on visit-to-visit blood pressure variability

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. 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. 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. 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.

Understanding Visit‐to‐Visit Blood Pressure Variability

Office blood pressure (BP) is considered the gold standard to estimate the risk accompanying an elevation in BP. In daily clinical practice, iterative determinations of office BP constitute the method to consider whether the control of BP is adequate, and frequently the value obtained in an isolated visit is used to modify the treatment of the patient without paying due attention to the values of BP obtained in previous visits. According to the new guidelines of the European Society of Hypertension and the European Society of Cardiology, adequate control is considered when office BP is <140/90 mm Hg for practically the whole population with hypertension.1 Values above this value have been typically considered as uncontrolled but without any reference to differences among visits. It is well known that BP is characterized by marked short-term fluctuations occurring within a 24-hour period. These short-term variations have been shown to be the result of complex interactions between extrinsic environmental and behavioral factors and intrinsic cardiovascular regulatory mechanism.2 Short-term BP variability has been analyzed using ambulatory BP monitoring and has been shown to increase with the development, progression, and severity of cardiac, vascular, and renal damage.2 Recently, the concept of visit-to-visit variability (VVV) obtained through the analysis of systolic BP (SBP) in the repetitive visits in a well-known trial, the Anglo-Scandinavian Cardiac Outcomes Trial-Blood Pressure Lowering Arm (ASCOT-BPLA), allowed Rothwell and colleagues3 to conclude in their post-hoc analysis that VVV in SBP and maximum SBP are strong predictors of stroke, independent of mean SBP. It is well established that adverse cardiovascular consequences of hypertension largely depend on absolute BP values and the concept of BP variability along the different visits to the doctor's office has added a new factor to be considered in order to obtain an adequate evaluation of risk and to pharmacologic therapy once this is started and maintained in hypertensive patients. After the initial publication, other groups have come to confirm, in post-hoc analyses, the relevance of VVV for the prediction of cardiovascular events and mortality in hypertensive patients and using data obtained in the general population.4-6 In the present issue of the Journal, Kostis and colleagues7 investigated the relevance of VVV during the very long-term follow-up (up to 17 years) of patients initially included in the Systolic Hypertension in the Elderly Program (SHEP). They confirmed that VVV was associated with cardiovascular death after 17 years of follow-up and after adjustment for confounding variables. This study had two other important advantages over previously published data. First, it was a placebo-controlled trial, which allowed the analysis of VVV in the placebo-treated group. Second, the influence of long-term adherence was considered, which allowed the investigation of the influence of this enormously important parameter on VVV. The relationship between VVV and cardiovascular outcome was significantly stronger in the active treatment group compared with the placebo. This could contribute, partly in agreement with previous data published in this Journal,8 to the hypothesis launched by the authors that inconsistent adherence to active therapy may be causally related to VVV as well as to the occurrence of cardiovascular death. Inconsistent adherence to placebo would be expected to have less influence on BP variability than active therapy. These findings expand the knowledge about the mechanisms underlying the existence of an increased VVV promoted either directly or through coexistent risk factors.3, 9 Another interesting aspect of the influence of active medication on VVV consists of its variation with time,6 with variability being more intense during the first year of follow-up, in which frequent changes in antihypertensive therapy take place and fluctuations in BP can be expected to occur before attaining the adequate amount of treatment required for sustained control of BP. With respect to the medication class effects on VVV, recent data10 have shown that diuretic therapy, as that used in SHEP, lowers BP variability, albeit the magnitude of the effect of antihypertensive medication class explained <10% of the VVV of BP. In summary, the data published in the study by Kostis and colleagues7 come to extend the understanding of VVV in BP, demonstrating that it is more important when active therapy is compared with placebo and introducing inconsistent adherence as a new factor that contributes to the understanding of this phenomenon, which has been shown to be relevant for the prognosis of hypertensive patients.

Visit-to-visit variability of blood pressure

Blood pressure (BP) is known to vary over time within individuals. Although variability between office visits has traditionally been regarded as a barrier to the accurate measurement of BP, several recent studies have reported strong associations between visit-to-visit variability (VVV) of BP and increased risk for cardiovascular outcomes. In this article, we review data on VVV of BP and outcomes, determinants of high VVV of BP including demographics, medical history, and antihypertensive medication classes and poor adherence. In addition, we will discuss methodological issues related to interpreting data from studies of VVV of BP and data on BP variability assessed outside of the office setting. In conclusion, we highlight pressing research needs related to VVV of BP including those aimed at determining the mechanism underlying high VVV of BP, assessing interventions that lower VVV of BP and the utility of quantifying VVV of BP using measurements obtained in routine clinical practice.

Low correlation between visit-to-visit variability and 24-h variability of blood pressure

visit-to-visit variability (VVV) of clinic systolic blood pressure (SBP) has been associated with cardiovascular disease risk. Given the need for obtaining blood pressure (BP) at multiple visits to calculate VVV, substituting BP variability from ambulatory blood pressure monitoring (ABPM) may be a practical alternative. We assessed the correlation between VVV of BP and BP variability from ABPM using data from 146 untreated, mostly normotensive participants (mean age 47.9 years), in a substudy of the ongoing Masked Hypertension Study. VVV of SBP and diastolic blood pressure (DBP) was estimated by the standard deviation (s.d.vvv) and average real variability (ARVvvv) from six study visits over a median of 216 days. ABPM data were used to calculate the day-night s.d. (s.d.dn), and the ARV of SBP and DBP over 24 h (ARV24). For SBP, the mean s.d.vvv and s.d.dn were 6.3 (s.d.=2.5) and 8.8 mm Hg (s.d.=1.8), respectively, and mean ARVvvv and ARV24 were 7.2 (s.d.=3.2) and 8.4 mm Hg (s.d.=2.1), respectively. Spearman's correlation coefficient between s.d.vvv and s.d.dn of SBP was rs=0.25, and between ARVvvv and ARV24 was rs=0.17. Participants in the highest quartile of s.d.dn of SBP were 1.66 (95% CI: 0.93-2.75) times more likely to be in the highest quartile of s.d.vvv of SBP. The observed-to-expected ratio between the highest quartiles of ARVvvv and ARV24 of SBP was 0.89 (95% CI: 0.41-1.69). The correlations for s.d.vvv and s.d.dn, and ARVvvv and ARV24 of DBP were minimal. These data suggest VVV and 24-h variability are weakly correlated and not interchangeable.

Associations of Aortic Distensibility and Arterial Elasticity With Long-Term Visit-to-Visit Blood Pressure Variability: The Multi-Ethnic Study of Atherosclerosis (MESA)

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