Blood pressure variability in elderly persons with white-coat and masked hypertension compared to those with normotension and sustained hypertension

Masked phenomenon: renal and cardiovascular complications; review and updates

BACKGROUND

In the in-clinic blood pressure (BP) recording setting, a sizable number of individuals with normal BP and approximately 30% of patients with chronic renal disease (CKD) exhibit elevated outpatient BP records. These individuals are known as masked hypertension (MHTN), and when they are on antihypertensive medications, but their BP is not controlled, they are called masked uncontrolled hypertension (MUHTN). The masked phenomenon (MP) (MHTN and MUHTN) increases susceptibility to end-organ damage (a two-fold greater risk for cardiovascular events and kidney dysfunction). The potential extension of the observed benefits of MP therapy, including a reduction in end-organ damage, remains questionable.

AIM AND METHODS

This review aims to study the diagnostic methodology, epidemiology, pathophysiology, and significance of MP management in end-organs, especially the kidneys, cardiovascular system, and outcomes. To achieve the purposes of this non-systematic comprehensive review, PubMed, Google, and Google Scholar were searched using keywords, texts, and phrases such as masked phenomenon, CKD and HTN, HTN types, HTN definition, CKD progression, masked HTN, MHTN, masked uncontrolled HTN, CKD onset, and cardiovascular system and MHTN. We restricted the search process to the last ten years to search for the latest updates.

CONCLUSION

MHTN is a variant of HTN that can be missed if medical professionals are unaware of it. Early detection by ambulatory or home BP recording in susceptible individuals reduces end-organ damage and progresses to sustained HTN. Adherence to the available recommendations when dealing with masked phenomena is justifiable; however, further studies and recommendation updates are required.

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

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

Analysis of Systolic Blood Pressure Level and Short-Term Variability in Masked Hypertension

Background

Patients with masked hypertension are at an elevated risk of cardiovascular events and all-cause death. This risk is close to that of sustained hypertension. The mean value and short-term variability of systolic blood pressure are considered to be risk factors for organ damage in hypertension.

Objective

To investigate the mean value and short-term variability of systolic blood pressure in patients with masked hypertension.

Methods

According to the results of in-clinic and ambulatory blood pressure measurement, participants were divided into four groups: normotension group, controlled hypertension group, masked hypertension group, and sustained hypertension group. The mean value and short-term variability of systolic blood pressure of masked hypertension group were evaluated by comparison with the other three groups.

Results

A total of 250 subjects were enrolled, with an average age of 65.46 ± 8.76 years, and 166 (66.4%) were male, including 62 in the normotension group, 78 in the controlled hypertension group, 69 in the masked hypertension group, and 41 in the sustained hypertension group. Compared with the normotension group and controlled hypertension group, the mean value, blood pressure load, standard deviation, and coefficient of variation of systolic blood pressure over 24 hours and during the day and night, were all higher in the masked hypertension group (P < 0.05), while the rate of the nocturnal systolic blood pressure decline was lower (P < 0.05). There were no statistically significant differences in the above indexes between the masked hypertension group and sustained hypertension group (P > 0.05).

Conclusion

There are higher mean value of systolic blood pressure and greater short-term variability in masked hypertension patients. Identification of masked hypertension is an important challenge in the clinic.

Current applications and limitations of European guidelines on blood pressure measurement: implications for clinical practice

Hypertension is the most common cardiovascular (CV) risk factor, strongly and independently associated with an increased risk of major CV outcomes, including myocardial infarction, stroke, congestive heart failure, renal disease and death due to CV causes. Effective control of hypertension is of key importance for reducing the risk of hypertension-related CV complications, as well as for reducing the global burden of CV mortality. However, several studies reported relatively poor rates of control of high blood pressure (BP) in a setting of real-life practice. To improve hypertension management and control, national and international scientific societies proposed several educational and therapeutic interventions, among which the systematic implementation of out-of-office BP measurements represents a key element. Indeed, proper assessment of individual BP profile, including home, clinic and 24-h ambulatory BP levels, may improve awareness of the disease, ensure high level of adherence to prescribed medications in treated hypertensive patients, and thus contribute to ameliorate BP control in treated hypertensive outpatients. In line with these purposes, recent European guidelines have released practical recommendations and clear indications on how, when and how properly measuring BP levels in different clinical settings, with different techniques and different methods. This review aimed at discussing current applications and potential limitations of European guidelines on how to measure BP in office and out-of-office conditions, and their potential implications in the daily clinical management of hypertension.

Masked Uncontrolled Hypertension Is Accompanied by Increased Out-of-Clinic Aldosterone Secretion

Masked uncontrolled hypertension (MUCH) in treated patients is defined as controlled office blood pressure (BP) but uncontrolled out-of-clinic ambulatory BP. Previously, we have shown that patients with MUCH have evidence of heightened out-of-clinic sympathetic nervous system activity. The aim is to test the hypothesis that MUCH patients have higher aldosterone secretion compared with patients with true controlled hypertension. Two hundred twenty-two patients were recruited after having controlled office BP readings at ≥3 clinic visits. Patients taking MR (mineralocorticoid receptor) antagonists and epithelial sodium channel blockers were excluded. All patients were evaluated by clinic automated office BP and morning serum aldosterone and plasma renin activity. Out-of-clinic ambulatory BP monitoring and 24-hour urinary aldosterone, catecholamines, and metanephrines were also measured. Sixty-four patients had MUCH, and the remaining 48 patients had true controlled hypertension. MUCH patients had significantly higher out-of-clinic levels of 24-hour urinary aldosterone, catecholamines, and metanephrines compared with true controlled hypertension. The 2 groups did not differ in serum aldosterone, plasma renin activity, or aldosterone-renin ratio collected in clinic. In addition, 32.8% of MUCH patients had high out-of-clinic 24-hour urinary aldosterone (≥12 µg) but normal clinic serum aldosterone (<15 ng/dL) and aldosterone-renin ratio (<20). Further, in correlation matrix analysis, higher 24-hour urinary catecholamines and metanephrines were associated with higher 24-hour urinary aldosterone and plasma renin activity levels in MUCH patients. Patients with MUCH have higher out-of-clinic urinary aldosterone levels compared with patients with true controlled hypertension. This study suggests that patients with MUCH likely have higher out-of-clinic sympathetic nervous system tone increases aldosterone secretion mediated by increased renin release that may contribute to their higher out-of-clinic BP.

Ambulatory blood pressure profile in office normotensive obese children: prevalence of masked hypertension and impact of parental hypertension

Objectives The objectives of this study were to analyze ambulatory blood pressure (ABP) data in office normotensive obese children, to determine the prevalence and characteristics of masked hypertension (MH) and to investigate the impact of parental hypertension (PH) on ABP. Methods Seventy-nine obese and 35 normal weight children were enrolled. Each weight group was further divided in accordance with the presence of PH. ABP was recorded in an outpatient setting. Results Obese children had higher systolic ABP (p<0.05) and heart rate (p<0.001) compared with normal weight children. In obese children with PH, only nighttime systolic ABP (p=0.01) was higher compared with obese without PH, whereas normal weight children with PH had higher 24 h and daytime systolic and diastolic BP (all p<0.05) and nighttime DBP (p<0.001) compared with those without PH. PH but not obesity was associated with nondipping phenomenon. Prevalence of MH in the whole group was 23.6% being significantly higher in obese than in nonobese subjects (31.6 vs. 5.7%; p=0.0026) as well as in obese subjects with PH compared with obese subjects without PH (48.7 vs. 15%; χ2=10.37; p=0.001). MH was diagnosed more frequently in obese with high-normal office BP compared with obese with normal office BP, although it did not reach statistical significance (50 vs. 26.2%; χ2=3.631; p=0.056). In the normal weight group, neither PH nor office BP category had an impact on the prevalence of MH. Conclusions Office normotensive obese children had higher ABP values. MH was associated with obesity, PH and high-normal BP.

Epidemiological Impact and Clinical Consequences of Masked Hypertension: A Narrative Review

Masked hypertension (MHT) is a clinical condition characterized by normal blood pressure (BP) levels during clinical consultation and above normal out-of-office BP values. MHT is associated to an increased risk of developing hypertension-mediated organ damage (HMOD) and major cardiovascular (CV) outcomes, such as myocardial infarction, stroke, and hospitalizations due to CV causes, as well as to metabolic abnormalities and diabetes, thus further promoting the development and progression of atherosclerotic disease. Previous studies showed contrasting data on prevalence and clinical impact of MHT, due to not uniform diagnostic criteria (including either home or 24-h ambulatory BP measurements, or both) and background antihypertensive treatment. Whatever the case, over the last few years the widespread diffusion of validated devices for home BP monitoring has promoted a better diagnostic assessment and proper identification of individuals with MHT in a setting of clinical practice, thus resulting in increased prevalence of this clinical condition with potential clinical and socio-economic consequences. Several other items, in fact, remain unclear and debated, particularly regarding the therapeutic approach to MHT. The aim of this narrative review is to illustrate the clinical definition of MHT, to analyze the diagnostic algorithm, and to discuss the potential pharmacological approaches to be adopted in this clinical condition, in the light of the recommendations of the recent European hypertension guidelines.

Blood Pressure Measurement and Treatment Decisions

White-coat and masked hypertension are important hypertension phenotypes. Out-of-office blood pressure measurement is essential for the accurate diagnosis and monitoring of these conditions. This review summarizes literature related to the detection and diagnosis, prevalence, epidemiology, prognosis, and treatment of white-coat and masked hypertension. Cardiovascular risk in white-coat hypertension appears to be dependent on the presence of coexisting risk factors, whereas patients with masked hypertension are at increased risk of target organ damage and cardiovascular events. There is an unmet need for robust data to support recommendations around the use of antihypertensive treatment for the management of white-coat and masked hypertension.

Association of Cardiovascular Outcomes With Masked Hypertension Defined by Home Blood Pressure Monitoring in a Japanese General Practice Population

Importance

The clinical outcomes associated with masked hypertension defined by home blood pressure monitoring (HBPM) in clinical settings remain uncertain.

Objective

To assess the association between masked hypertension and cardiovascular disease events in clinical settings.

Design, Setting, and Participants

This observational cohort study used data from 4261 outpatients treated at 71 primary practices or university hospitals throughout Japan who were enrolled in the Japan Morning Surge-Home Blood Pressure study between January 1, 2005, and December 31, 2012. Participants had a history of or risk factors for cardiovascular disease and were followed up through March 31, 2015. Participants underwent clinic blood pressure (BP) measurements on 2 occasions as well as HBPM measurements in the morning and evening for a 14-day period. Urine albumin to creatinine ratio and circulating brain (or B-type) natriuretic peptide levels were quantified at baseline as a marker of cardiovascular end-organ damage. Data were analyzed from July 1, 2017, to October 31, 2017.

Exposures

Participants were categorized into 4 BP groups: (1) masked hypertension-hypertensive home BP levels (systolic, ≥135 mm Hg; diastolic, ≥85 mm Hg) and nonhypertensive clinic BP levels (systolic, <140 mm Hg; diastolic, <90 mm Hg); (2) white-coat hypertension-nonhypertensive home BP levels (systolic, <135 mm Hg; diastolic, <85 mm Hg) and hypertensive clinic BP levels (systolic, ≥140 mm Hg; diastolic, ≥90 mm Hg); (3) sustained hypertension-hypertensive home and clinic BP levels; and (4) controlled BP-nonhypertensive home and clinic BP levels.

Main Outcomes and Measures

Incident stroke and coronary heart disease.

Results

Of the 4261 participants, 2266 (53.2%) were women, 3374 (79.2%) were taking antihypertensive medication, and the mean (SD) age was 64.9 (10.9) years. During a median (interquartile range) follow-up of 3.9 (2.4-4.6) years, 74 stroke (4.4 per 1000 person-years) and 77 coronary heart disease (4.6 per 1000 person-years) events occurred. The masked hypertension group had a greater risk for stroke compared with the controlled BP group (hazard ratio, 2.77; 95% CI, 1.20-6.37), independent of traditional cardiovascular risk factors, urine albumin to creatinine ratio, and circulating B-type natriuretic peptide levels. Conversely, masked hypertension yielded no association with coronary heart disease risk.

Conclusions and Relevance

In the Japanese general practice population, masked hypertension defined by HBPM may be associated with an increased risk for stroke events. Use of HBPM may improve the assessment of BP-related risks and identify new therapeutic interventions aimed at preventing cardiovascular disease events.

Masked hypertension and cardiovascular outcomes: an updated systematic review and meta-analysis

Background

As many as one-third of individuals with normal office blood pressure (BP) are diagnosed with masked hypertension (HTN) based on ambulatory BP measurements (ABPM). Masked HTN is associated with higher risk of sustained HTN (SH) and increased cardiovascular morbidity.

Methods

The present study was designed to systematically review cohort studies and assess the effects of masked HTN compared to normotension and SH on cardiovascular events and all-cause mortality. We systematically searched the electronic databases, such as MEDLINE, PubMed, Embase, and Cochrane for prospective cohort studies, which evaluated participants with office and ambulatory and/or home BP.

Results

We included nine studies with a total number of 14729 participants (11245 normotensives, 3484 participants with masked HTN, 1984 participants with white-coat HTN, and 5143 participants with SH) with a mean age of 58 years and follow-up of 9.5 years. Individuals with masked HTN had significantly increased rates of cardiovascular events and all-cause mortality than normotensives and white-coat HTN and had lower rates of cardiovascular events than those with SH (odds ratio 0.61, 95% confidence interval 0.42–0.89; P=0.010; I²=84%). Among patients on antihypertensive treatment, masked HTN was associated with higher rates of cardiovascular events than in those with normotension and white-coat HTN and similar rates of cardiovascular events in those with treated SH.

Conclusion

Prompt screening of high-risk individuals with home BP measurements and ABPM, the diagnosis of masked HTN, and the initiation of treatment, may mitigate the adverse cardiovascular effects of masked HTN.

The significance of blood pressure variation and metabolic risk factors in patients with different stages of hypertension

Objectives Blood pressure variation (BPV) and metabolic syndrome is an independent risk factor for cardiovascular events. Ambulatory blood Pressure (ABP) has been shown to be more closely related to cardiovascular events in hypertensive patients than conventional office BP (OBP). Using both OBP and ABP, 4 groups of patients were identified: (1) normotensive patients (NT); (2) white coat hypertensives (WCHT); (3) masked hypertensives (MHT); and (4) sustainedhypertensives (SHT). We investigated the significance of BPV and metabolic risks of these 4 groups. Methods This study is a retrospective analysis of patients between January 2008 and May 2013. Echocardiography and 24 hour ABP monitoring were performed. Results BMI was significantly higher in the MHT compared with the NT. There were progressive increases in fasting glucose level from NT to WCHT, MHT, and SHT.MHT and SHT had higher 24h and nighttime BPV than NT.MHT was significantly related with BMI (r = 0.139, P = 0.010), creatinine (r = 0.144, P = 0.018), fasting glucose (r = 0.128, P = 0.046), daytime systolic BPV (r = 0.130, P = 0.017), and daytime diastolic BPV (r = 0.130, P = 0.017). Dyslipidemia (r = 0.110, P = 0.043), nighttime systolic BPV (r = 0.241, P &lt; 0.001) and nighttime diastolic BPV (r = 0.143, P = 0.009) shown correlation with SHT. In multivariate logistic regression, MHT was independently associated with Body mass index (OR 1.086, 95% CI 1.005–1.174, P = 0.038) and creatinine (OR 1.005, 95% CI 1.001–1.010, P = 0.045). Conclusions BPV and metabolic risk factors were found to be greater in MHT and SHT compared with NT and WCHT. This suggests that BPV and metabolic risks may contribute to the elevated cardiovascular risk observed in patients with MHT and SHT.

Masked hypertension: understanding its complexity

Masked hypertension, which is present when in-office normotension translates to out-of-office hypertension, is present in a surprisingly high percentage of untreated persons and an even higher percentage of patients after beginning antihypertensive medication. Not only are persons with prehypertension more likely to have masked hypertension than those with optimal blood pressure (BP), but also they frequently develop target organ damage prior to transitioning to sustained hypertension. Furthermore, the frequency of masked hypertension is high in individuals of African inheritance and in the presence of increased cardiovascular risk factors and disease states, such as diabetes and chronic renal failure. Nocturnal hypertension and non-dipping may be early markers of masked hypertension. Twenty-four hour ambulatory BP monitoring (ABPM), which can detect nighttime and 24 h elevated BP, remains the gold standard for diagnosing masked hypertension. Almost one-third of treated patients with masked hypertension remain as 'masked uncontrolled hypertension', and it becomes important, therefore, to use ABPM (and supplemental home BP monitoring) for the effective diagnosis and control of hypertension.

Blood Pressure Trajectories and the Risk of Intracerebral Hemorrhage and Cerebral Infarction: A Prospective Study

The association between long-term blood pressure (BP) patterns in community-dwelling adults and risk of intracerebral hemorrhage and cerebral infarction is not well characterized. This prospective study included 79 385 participants, free of stroke, myocardial infarction, and cancer in or before 2010 (baseline). Systolic BP trajectories were identified using latent mixture modeling with data from 2006, 2008, and 2010. Incident cases of intracerebral hemorrhage and cerebral infarction occurred during 2010 to 2014, confirmed by review of medical records, by 3 physicians. We identified 5 distinct systolic BP trajectories during 2006 to 2010. Each of the trajectories was labeled according to their BP range and pattern over time: normotensive-stable (n=26 740), prehypertension-stable (n=35 674), stage 1 hypertension-increasing (n=8215), stage 1 hypertension-decreasing (n=6422), and stage 2 hypertension-stable (n=2334). We documented 1034 incident cases of cerebral infarction and 187 cases of intracerebral hemorrhage. Although the prehypertension-stable trajectory exhibited systolic BP range within the normal range (120-140 mm Hg) during 2006 to 2010, this group had higher stroke risk relative to the normotensive-stable group (<120 mm Hg) (adjusted hazard ratio was 3.11 for intracerebral hemorrhage and 1.99 for cerebral infarction; P<0.001 for both), after adjusting for possible confounders. Individuals in the stage 2 hypertension-stable systolic BP trajectory (175-179 mm Hg) had the highest risk of intracerebral hemorrhage (adjusted hazard ratio was 12.4) and cerebral infarction (adjusted hazard ratio was 5.07), relative to the normotensive-stable group (P<0.001 for both). BP trajectories were associated with the risk of stroke and increasing BP trajectories within the currently designated normal range may still increase the risk for stroke.

Higher Blood Pressure Variability in White Coat Hypertension; from the Korean Ambulatory Blood Pressure Monitoring Registry

BACKGROUND AND OBJECTIVES

Blood pressure variability (BPV) was recently shown to be a risk factor of stroke. White coat hypertension (WCH) used to be regarded as innocuous, but one long-term follow-up study reported that WCH increased stroke rate compared to normotension (NT). In this study, we aimed to evaluate the relationship between WCH and BPV.

SUBJECTS AND METHODS

We analyzed 1398 subjects from the Korean Ambulatory Blood Pressure Registry, who were divided into NT (n=364), masked hypertension (n=122), white coat hypertension (n=254), and sustained hypertension (n=658) groups.

RESULTS

Baseline characteristics were similar among groups. The average real variability (ARV), a highly sensitive BPV parameter, was highest in the WCH group, followed by the sustained hypertension, masked hypertension, and NT groups. The results persisted after being adjusted for covariates. The WCH vs. sustained hypertension results (adjusted mean±standard error) were as follows: 24-h systolic ARV, 22.9±0.8 vs. 19.4±0.6; 24-h diastolic ARV, 16.8±0.6 vs. 14.3±0.5; daytime systolic ARV, 21.8±0.8 vs. 16.8±0.6; and daytime diastolic ARV, 16.2±0.6 vs. 13.4±0.5 (p<0.001 for all comparisons).

CONCLUSION

From the registry data, we found that subjects with WCH or masked hypertension had higher BPV than NT. However, long-term follow-up data assessing the clinical influences of WCH on stroke are needed.

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

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

The complexity of masked hypertension: diagnostic and management challenges

Masked hypertension, defined as discordant in-office normotension versus out-of-office hypertension, is present in approximately 10 % to 40 % of patients not receiving antihypertensive treatment. Not only are persons with prehypertension more likely to have masked hypertension, but they also frequently develop target organ damage before transitioning to established sustained hypertension. Moreover, the percentage of persons with masked hypertension increases in the presence of cardiovascular disease, diabetes, or chronic renal failure. The gold standard for diagnosing masked hypertension is the 24-hour ambulatory BP monitor (ABPM), but home BP monitoring (HBPM) has also been a useful alternative procedure. Importantly, initiating antihypertensive treatment exclusively with the use of in-office BP monitoring may result in almost one-third of patients remaining with high-risk masked uncontrolled hypertension, which underscores the importance of HBPM and ABPM as supplements to in-office BP monitoring for the effective treatment of hypertension.

Epidemiology of masked and white-coat hypertension: the family-based SKIPOGH study

Objective

We investigated factors associated with masked and white-coat hypertension in a Swiss population-based sample.

Methods

The Swiss Kidney Project on Genes in Hypertension is a family-based cross-sectional study. Office and 24-hour ambulatory blood pressure were measured using validated devices. Masked hypertension was defined as office blood pressure<140/90 mmHg and daytime ambulatory blood pressure≥135/85 mmHg. White-coat hypertension was defined as office blood pressure≥140/90 mmHg and daytime ambulatory blood pressure<135/85 mmHg. Mixed-effect logistic regression was used to examine the relationship of masked and white-coat hypertension with associated factors, while taking familial correlations into account. High-normal office blood pressure was defined as systolic/diastolic blood pressure within the 130–139/85–89 mmHg range.

Results

Among the 652 participants included in this analysis, 51% were female. Mean age (±SD) was 48 (±18) years. The proportion of participants with masked and white coat hypertension was respectively 15.8% and 2.6%. Masked hypertension was associated with age (odds ratio (OR) = 1.02, p = 0.012), high-normal office blood pressure (OR = 6.68, p<0.001), and obesity (OR = 3.63, p = 0.001). White-coat hypertension was significantly associated with age (OR = 1.07, p<0.001) but not with education, family history of hypertension, or physical activity.

Conclusions

Our findings suggest that physicians should consider ambulatory blood pressure monitoring for older individuals with high-normal office blood pressure and/or who are obese.

Blood pressure variability assessed by home measurements: a systematic review

Accumulating evidence suggests that day-by-day blood pressure (BP) variability assessed using self-measurements by patients at home (HBPV) provides useful information beyond that of average home BP. This systematic review summarizes the current evidence on day-by-day HBPV. A systematic literature search (PubMed) revealed 22 eligible articles. Independent prognostic value of day-by-day HBPV for cardiovascular events and total mortality was demonstrated in two outcome studies, whereas novel indices of variability had minimal or no independent prognostic ability. Although findings are not consistent among the studies, the evidence suggests that HBPV has an independent role in the progression of preclinical cardiac, arterial and renal damage and is affected by age, gender, average BP and heart rate level, antihypertensive treatment, antihypertensive drug class and other factors. However, there is large diversity among the available studies in the home BP monitoring protocols, the indices used to quantify HBPV and the end points selected for evaluation. Overall, these preliminary data largely based on heterogeneous studies indicate an important and independent role of day-by-day HBPV in the pathogenesis of hypertension-induced cardiovascular damage. Yet, fundamental questions remain unanswered, including the optimal variability index, the optimal home monitoring schedule required, the threshold that defines increased HBPV and the impact of treatment-induced variability change on organ damage and cardiovascular events. Until these questions are adequately addressed in future studies, HBPV should largely remain a research issue with limited practical value for individual patients.

Comparison of noninvasive assessments of central blood pressure using general transfer function and late systolic shoulder of the radial pressure wave

BACKGROUND

Central systolic blood pressure (cSBP) can be derived by the general transfer function of the radial pressure wave, as used in the SphygmoCor device, or by regression equation from directly measured late systolic shoulder of the radial pressure wave (pSBP2), as used in the Omron HEM-9000AI device. The aim of this study was to compare the SphygmoCor estimates of cSBP with 2 estimates of cSBP provided by the Omron HEM-9000AI (cSBP, pSBP2) in a large cohort of the white population.

METHODS

In 391 patients aged 52.3±13.5 years (46% men) from the Czech post-MONICA Study, cSBP was measured using the SphygmoCor and Omron HEM-9000AI devices in random order.

RESULTS

Omron cSBP and pSBP2 were perfectly correlated (r = 1.0; P < 0.0001). There was a strong correlation (r = 0.97; P < 0.0001) between Omron and SphygmoCor cSBP estimates, but Omron estimate was 13.1±4.7mm Hg higher than SphygmoCor cSBP. On the other hand, Omron pSBP2 strongly correlated with SphygmoCor cSBP (r = 0.97; P < 0.0001) and was 1.7±4.2mm Hg lower than SphygmoCor cSBP. In multivariable analysis, anthropometric and cardiovascular risk factors explained only 10% of the variance of the cSBP difference between devices while explaining 52% of the systolic blood pressure amplification variance.

CONCLUSIONS

Estimation of cSBP based on the late systolic shoulder of the radial wave provides a comparable accuracy with the validated general transfer function. When comparing Omron HEM-9000AI and SphygmoCor estimates of cSBP, Omron pSBP2 should be used. The difference between both devices in cSBP may be explained by differences in calibration.