Franz Volhard lecture: should doctors still measure blood pressure? The missing patients with masked hypertension

The association between depressive symptoms and masked hypertension in participants with normotension measured at research center

Masked hypertension is a risk factor for cardiovascular diseases. However, masked hypertension is sometimes overlooked owing to the requirement for home blood pressure measurements for diagnosing. Mental status influences blood pressure. To reduce undiagnosed masked hypertension, this study assessed the association between depressive symptoms and masked hypertension. This cross-sectional study used data from the Tohoku Medical Megabank Project Community-Based Cohort Study (conducted in Miyagi Prefecture, Japan, from 2013) and included participants with normotension measured at the research center (systolic blood pressure<140 mmHg and diastolic blood pressure <90 mmHg). Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (Japanese version). Masked hypertension was defined as normotension measured at the research center and home hypertension (home systolic blood pressure ≥135 mmHg or home diastolic blood pressure ≥85 mmHg). The study comprised 6705 participants (mean age: 55.7 ± 13.7 years). Of these participants, 1106 (22.1%) without depressive symptoms and 393 (23.2%) with depressive symptoms were categorized to have masked hypertension. Sex-specific and age-adjusted least mean squares for home blood pressure, not for research blood pressure were significantly higher in the group with depressive symptoms in both sex categories. The multivariate odds ratio for masked hypertension in the patients with depressive symptoms was 1.72 (95% confidence interval: 1.26-2.34) in male participants and 1.30 (95% confidence interval: 1.06-1.59) in female ones. Depressive symptoms were associated with masked hypertension in individuals with normotension measured at the research center. Depressive symptoms may be one of the risk factors for masked hypertension. Depressive symptoms were associated with masked hypertension in individuals with normotension measured at research center.

Blood Pressure and Cardiovascular Disease Mortality Among US Adults: A Sex-Stratified Analysis, 1999-2019

BACKGROUND

Most research examining the association between blood pressure (BP) and cardiovascular disease (CVD) is sex-agnostic. Our goal was to assess sex-specific associations between BP and CVD mortality.

METHODS

We combined ten cycles of the National Health and Nutrition Examination Survey (1999-2018), N=53 289. Blood pressure was measured 3× and averaged. Data were linked to National Death Index data, and CVD mortality through December 31, 2019, was defined from International Classification of Diseases, Tenth Revision codes. We estimated sex-stratified, multivariable-adjusted incidence rate ratios (IRRs) for CVD mortality.

RESULTS

Over a median follow-up of 9.5 years, there were 2405 CVD deaths. Associations between categories of systolic blood pressure (SBP) and diastolic blood pressure (DBP) with CVD mortality differed by sex (P<0.01). Among men, compared with SBP of 100 to <110 mm Hg, CVD mortality was 76% higher with SBP ≥160 mm Hg (IRR, 1.76 [95% CI, 1.27-2.44]). Among women, compared with SBP 100 to < 110 mm Hg, CVD mortality was 61% higher with SBP 130 to 139 mm Hg (IRR, 1.61 [95% CI, 1.02-2.55]), 75% higher with SBP 140 to 159 mm Hg (IRR, 1.75 [95% CI, 1.09-2.80]), and 113% higher with SBP≥160 mm Hg (IRR, 2.13 [95% CI, 1.35-3.36]). Compared with DBP 70 to <80 mm Hg, CVD mortality was higher with DBP <70 mm Hg and DBP≥80 mm Hg among men, and higher with DBP <50 mm Hg and DBP≥80 mm Hg among women.

CONCLUSIONS

The association between BP and CVD mortality differed by sex, with increased CVD mortality risk present at lower levels of systolic blood pressure among women compared with men.

Patients' acceptance of less blood pressure measurement in consultation: a cross-sectional study in general practice

PURPOSE

Blood pressure (BP) is measured at almost every general practitioner (GP) consultation in the region of Auvergne, France. A 2018 qualitative study shows that GPs measure BP to satisfy patients, whereas patients declare themselves indifferent to the absence of the measurement. The objective was to validate the results of a qualitative study, to quantitatively assess patient satisfaction when BP is not measured, and to study the factors associated with the degree of patient satisfaction.

METHODS

This was a quantitative observational study conducted using self-questionnaires among patients in medical practices in Auvergne.

RESULTS

Four hundred and ninety-two questionnaires were evaluated in 20 medical practices. Sixty percent of patients had indifferent or favorable feelings in the absence of BP measurement. In bivariate analysis, young age, male sex, absence of pathology, and low frequency of visits were associated with indifferent or favorable feelings in the absence of BP measurement. In multivariable analysis, a history of hypertension and psychiatric history were associated with unfavorable feelings. The intraclass correlation coefficient for practice-related variability was 5.6%. Patients' susceptibility to having particularly favorable or unfavorable feelings could be related to their GP (physician effect).

CONCLUSION

The hypothesis put forward in the qualitative study is confirmed: the majority of patients are in favor of or indifferent to the absence of BP measurement in general practice. General practice could be more efficient by measuring BP less frequently and better.

Unmasking left ventricular systolic dysfunction in masked hypertension: looking at myocardial strain. A review and meta-analysis

BACKGROUND AND AIM

A growing body of evidence supports the view that masked hypertension (MH) (i.e. normal office and elevated out-of-office BP) is a blood pressure (BP) phenotype associated with increased risk of subclinical organ damage, cardiovascular disease and death as compared to true normotension. Whether left ventricular (LV) systolic function is impaired in individuals with MH is still a poorly defined topic. Therefore, we aimed to provide a new piece of information on LV systolic dysfunction in the untreated MH setting, focusing on speckle tracking echocardiography (STE) studies investigating LV global longitudinal strain (GLS), a more sensitive index of systolic function than conventional LV ejection fraction (LVEF).

METHODS

A computerized search was performed using Pub-Med, OVID, EMBASE and Cochrane library databases from inception until June 30, 2022. Full articles reporting data on LV GLS in MH, as assessed by ambulatory BP monitoring (ABPM), and normotensive controls were considered suitable for the purposes of review and meta-analysis.

RESULTS

A total of 329 untreated individuals with MH and 376 normotensive controls were included in six studies. While pooled average LVEF was not different between groups [64.5 ± 1.5 and 64.5 ± 1.3%, respectively, standard means difference (SMD): -0.002 ± 0.08, confidence interval (CI): 0.15/-0.15, P = 0.98), LV GLS was worse in MH patients than in normotensive counterparts (-18.5 ± 0.70 vs. -20.0 ± 0.34%, SMD: 0.68 ± 0.28, CI: 0.12/1.24, P < 0.01).

CONCLUSIONS

Our findings suggest that early changes in LV systolic function not detectable by conventional echocardiography in the MH setting can be unmasked by STE and that its implementation of STE in current practice may improve the detection of subclinical organ damage of adverse prognostic significance.

Methods of Blood Pressure Measurement to Predict Hypertension-Related Cardiovascular Morbidity and Mortality

PURPOSE OF REVIEW

As the evidence on different blood pressure phenotypes and their cardiovascular risks evolve, it is imperative to evaluate the reliability of office blood pressure (OBP), ambulatory blood pressure (ABP), and home blood pressure (HBP) measurements and their associations with cardiovascular morbidity and mortality.

RECENT FINDINGS

HBP is more reliable in diagnosis of hypertension than OBP or ABP. HBP correlates better with left ventricular mass index (LVMI). Increasing systolic HBP is associated with a higher risk of all-cause mortality, cardiovascular mortality, and cardiovascular events. An elevated systolic ABP is also associated with a higher risk of cardiovascular events and mortality. ABP is a better predictor of cardiovascular events than OBP in diabetics. ABP and HBP furnish additional information beyond OBP. They correlate better with cardiovascular outcomes and are more helpful with monitoring therapy than OBP. Comparative effectiveness studies of all three methods associating with cardiovascular outcomes are warranted.

Reliability of Office, Home, and Ambulatory Blood Pressure Measurements and Correlation With Left Ventricular Mass

BACKGROUND

Determining the reliability and predictive validity of office blood pressure (OBP), ambulatory BP (ABP), and home BP (HBP) can inform which is best for diagnosing hypertension and estimating risk of cardiovascular disease.

OBJECTIVES

This study aimed to assess the reliability of OBP, HBP, and ABP and evaluate their associations with left ventricular mass index (LVMI) in untreated persons.

METHODS

The Improving the Detection of Hypertension (IDH) study, a community-based observational study, enrolled 408 participants who had OBP assessed at 3 visits, and completed 3 weeks of HBP, 2 24-h ABP recordings, and a 2-dimensional echocardiogram. Mean age was 41.2 ± 13.1 years, 59.5% were women, 25.5% African American, and 64.0% Hispanic.

RESULTS

The reliability of 1 week of HBP, 3 office visits with mercury sphygmomanometry, and 24-h ABP were 0.938, 0.894, and 0.846 for systolic and 0.918, 0.847, and 0.843 for diastolic BP, respectively. The correlations among OBP, HBP, and ABP, corrected for regression dilution bias, were 0.74 to 0.89. After multivariable adjustment including OBP and 24-h ABP, 10 mm Hg higher systolic and diastolic HBP were associated with 5.07 (standard error [SE]: 1.48) and 3.92 (SE: 2.14) g/m² higher LVMI, respectively. After adjustment for HBP, neither systolic or diastolic OBP nor ABP was associated with LVMI.

CONCLUSIONS

OBP, HBP, and ABP assess somewhat distinct parameters. Compared with OBP (3 visits) or 24-h ABP, systolic and diastolic HBP (1 week) were more reliable and more strongly associated with LVMI. These data suggest that 1 week of HBP monitoring may be the best approach for diagnosing hypertension.

Optimización del desempeño del observador al medir la presión arterial en el consultorio: declaración de posición de la Comisión Lancet de Hipertensión

La hipertensión arterial es una causa modificable muy prevalente de enfermedades cardiovasculares, accidentes cerebrovasculares y muerte. Medir con exactitud la presión arterial es fundamental, dado que un error de medición de 5 mmHg puede ser motivo para clasificar incorrectamente como hipertensas a 84 millones de personas en todo el mundo. En la presente declaración de posición se resumen los procedimientos para optimizar el desempeño del observador al medir la presión arterial en el consultorio, con atención especial a los entornos de ingresos bajos o medianos, donde esta medición se ve complicada por limitaciones de recursos y tiempo, sobrecarga de trabajo y falta de suministro eléctrico. Es posible reducir al mínimo muchos errores de medición con una preparación adecuada de los pacientes y el uso de técnicas estandarizadas. Para simplificar la medición y prevenir errores del observador, deben usarse tensiómetros semiautomáticos o automáticos de manguito validados, en lugar del método por auscultación. Pueden ayudar también la distribución de tareas, la creación de un área específica de medición y el uso de aparatos semiautomáticos o de carga solar. Es fundamental garantizar la capacitación inicial y periódica de los integrantes del equipo de salud. Debe considerarse la implementación de programas de certificación de bajo costo y fácilmente accesibles con el objetivo de mejorar la medición de la presión arterial.

Optimizing observer performance of clinic blood pressure measurement: a position statement from the Lancet Commission on Hypertension Group

High blood pressure (BP) is a highly prevalent modifiable cause of cardiovascular disease, stroke, and death. Accurate BP measurement is critical, given that a 5-mmHg measurement error may lead to incorrect hypertension status classification in 84 million individuals worldwide. This position statement summarizes procedures for optimizing observer performance in clinic BP measurement, with special attention given to low-to-middle-income settings, where resource limitations, heavy workloads, time constraints, and lack of electrical power make measurement more challenging. Many measurement errors can be minimized by appropriate patient preparation and standardized techniques. Validated semi-automated/automated upper arm cuff devices should be used instead of auscultation to simplify measurement and prevent observer error. Task sharing, creating a dedicated measurement workstation, and using semi-automated or solar-charged devices may help. Ensuring observer training, and periodic re-training, is critical. Low-cost, easily accessible certification programs should be considered to facilitate best BP measurement practice.

Long Working Hours and the Prevalence of Masked and Sustained Hypertension

Previous studies on the effect of long working hours on blood pressure have shown inconsistent results. Mixed findings could be attributable to limitations related to blood pressure measurement and the lack of consideration of masked hypertension. The objective was to determine whether individuals who work long hours have a higher prevalence of masked and sustained hypertension. Data were collected at 3-time points over 5 years from 3547 white-collar workers. Long working hours were self-reported, and blood pressure was measured using Spacelabs 90207. Workplace clinic blood pressure was defined as the mean of the first 3readings taken at rest at the workplace. Ambulatory blood pressure was defined as the mean of the next readings recorded every 15 minutes during daytime working hours. Masked hypertension was defined as clinic blood pressure < 140/90 mm Hg and ambulatory blood pressure ≥135/85 mm Hg. Sustained hypertension was defined as clinic blood pressure ≥140/90 mm Hg and ambulatory blood pressure ≥135/85 mm Hg or being treated hypertension. Long working hours were associated with the prevalence of masked hypertension (prevalence ratio 49+ =1.70 [95% CI, 1.09–2.64]), after adjustment for sociodemographics, lifestyle-related risk factors, diabetes mellitus, family history of cardiovascular disease, and job strain. The association with sustained hypertension was of a comparable magnitude (prevalence ratio 49+ =1.66 [95% CI, 1.15–2.50]). Results suggest that long working hours are an independent risk factor for masked and sustained hypertension. Workplace strategies targeting long working hours could be effective in reducing the clinical and public health burden of hypertension.

Measurement of Blood Pressure in Humans: A Scientific Statement From the American Heart Association

The accurate measurement of blood pressure (BP) is essential for the diagnosis and management of hypertension. This article provides an updated American Heart Association scientific statement on BP measurement in humans. In the office setting, many oscillometric devices have been validated that allow accurate BP measurement while reducing human errors associated with the auscultatory approach. Fully automated oscillometric devices capable of taking multiple readings even without an observer being present may provide a more accurate measurement of BP than auscultation. Studies have shown substantial differences in BP when measured outside versus in the office setting. Ambulatory BP monitoring is considered the reference standard for out-of-office BP assessment, with home BP monitoring being an alternative when ambulatory BP monitoring is not available or tolerated. Compared with their counterparts with sustained normotension (ie, nonhypertensive BP levels in and outside the office setting), it is unclear whether adults with white-coat hypertension (ie, hypertensive BP levels in the office but not outside the office) have increased cardiovascular disease risk, whereas those with masked hypertension (ie, hypertensive BP levels outside the office but not in the office) are at substantially increased risk. In addition, high nighttime BP on ambulatory BP monitoring is associated with increased cardiovascular disease risk. Both oscillometric and auscultatory methods are considered acceptable for measuring BP in children and adolescents. Regardless of the method used to measure BP, initial and ongoing training of technicians and healthcare providers and the use of validated and calibrated devices are critical for obtaining accurate BP measurements.

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.

How do family physicians measure blood pressure in routine clinical practice? National survey of Canadian family physicians

OBJECTIVE

To describe the techniques currently used by family physicians in Canada to measure blood pressure (BP) for screening for, diagnosing, and treating hypertension.

DESIGN

A Web-based cross-sectional survey distributed by e-mail.

SETTING

Stratified random sample of family physicians in Canada.

PARTICIPANTS

Family physician members of the College of Family Physicians of Canada with valid e-mail addresses.

MAIN OUTCOME MEASURES

Physicians' self-reported routine methods for recording BP in their practices to screen for, diagnose, and manage hypertension.

RESULTS

A total of 774 valid responses were received, for a response rate of 16.2%. Respondents were similar to nonrespondents except for underrepresentation of male physicians. Of 769 respondents, 417 (54.2%) indicated that they used manual office BP measurement with a mercury or aneroid device and stethoscope as the routine method to screen patients for high BP, while 42.9% (330 of 769) reported using automated office BP (AOBP) measurement. The method most frequently used to make a diagnosis of hypertension was AOBP measurement (31.1%, 240 of 771), followed by home BP measurement (22.4%, 173 of 771) and manual office BP measurement (21.4%, 165 of 771). Ambulatory BP monitoring (ABPM) was used for diagnosis by 14.4% (111 of 771) of respondents. The most frequently reported method for ongoing management was home BP monitoring (68.7%, 528 of 769), followed by manual office BP measurement (63.6%, 489 of 769) and AOBP measurement (59.2%, 455 of 769). More than three-quarters (77.8%, 598 of 769) of respondents indicated that ABPM was readily available for their patients.

CONCLUSION

Canadian family physicians exhibit overall high use of electronic devices for BP measurement, However, more efforts are needed to encourage practitioners to follow current Canadian guidelines, which advocate the use of AOBP measurement for hypertension screening, ABPM and home BP measurement for making a diagnosis, and both AOBP and home BP monitoring for ongoing management.

Prevalence of Masked Hypertension Among US Adults With Nonelevated Clinic Blood Pressure

Masked hypertension (MHT), defined as nonelevated blood pressure (BP) in the clinic setting and elevated BP assessed by ambulatory monitoring, is associated with increased risk of target organ damage, cardiovascular disease, and mortality. Currently, no estimate of MHT prevalence exists for the general US population. After pooling data from the Masked Hypertension Study (n = 811), a cross-sectional clinical investigation of systematic differences between clinic BP and ambulatory BP (ABP) in a community sample of employed adults in the New York City metropolitan area (2005-2012), and the National Health and Nutrition Examination Survey (NHANES; 2005-2010; n = 9,316), an ongoing nationally representative US survey, we used multiple imputation to impute ABP-defined hypertension status for NHANES participants and estimate MHT prevalence among the 139 million US adults with nonelevated clinic BP, no history of overt cardiovascular disease, and no use of antihypertensive medication. The estimated US prevalence of MHT in 2005-2010 was 12.3% of the adult population (95% confidence interval: 10.0, 14.5)-approximately 17.1 million persons aged ≥21 years. Consistent with prior research, estimated MHT prevalence was higher among older persons, males, and those with prehypertension or diabetes. To our knowledge, this study provides the first estimate of US MHT prevalence-nearly 1 in 8 adults with nonelevated clinic BP-and suggests that millions of US adults may be misclassified as not having hypertension.

Masked Hypertension and Incident Clinic Hypertension Among Blacks in the Jackson Heart Study

Masked hypertension, defined as nonelevated clinic blood pressure (BP) and elevated out-of-clinic BP may be an intermediary stage in the progression from normotension to hypertension. We examined the associations of out-of-clinic BP and masked hypertension using ambulatory BP monitoring with incident clinic hypertension in the Jackson Heart Study, a prospective cohort of blacks. Analyses included 317 participants with clinic BP <140/90 mm Hg, complete ambulatory BP monitoring, who were not taking antihypertensive medication at baseline in 2000 to 2004. Masked daytime hypertension was defined as mean daytime blood pressure ≥135/85 mm Hg, masked night-time hypertension as mean night-time BP ≥120/70 mm Hg, and masked 24-hour hypertension as mean 24-hour BP ≥130/80 mm Hg. Incident clinic hypertension, assessed at study visits in 2005 to 2008 and 2009 to 2012, was defined as the first visit with clinic systolic/diastolic BP ≥140/90 mm Hg or antihypertensive medication use. During a median follow-up of 8.1 years, there were 187 (59.0%) incident cases of clinic hypertension. Clinic hypertension developed in 79.2% and 42.2% of participants with and without any masked hypertension, 85.7% and 50.4% with and without masked daytime hypertension, 79.9% and 43.7% with and without masked night-time hypertension, and 85.7% and 48.2% with and without masked 24-hour hypertension, respectively. Multivariable-adjusted hazard ratios (95% confidence interval) of incident clinic hypertension for any masked hypertension and masked daytime, night-time, and 24-hour hypertension were 2.13 (1.51-3.02), 1.79 (1.24-2.60), 2.22 (1.58-3.12), and 1.91 (1.32-2.75), respectively. These findings suggest that ambulatory BP monitoring can identify blacks at increased risk for developing clinic hypertension.

Conventional and Ambulatory Blood Pressure as Predictors of Retinal Arteriolar Narrowing

Supplemental Digital Content is available in the text.

At variance with the long established paradigm that retinal arteriolar narrowing trails hypertension, several longitudinal studies, all based on conventional blood pressure (CBP) measurement, proposed that retinal arteriolar narrowing indicates heightened microvascular resistance and precedes hypertension. In 783 randomly recruited Flemish (mean age, 38.2 years; 51.3% women), we investigated to what extent CBP and daytime (10 am to 8 pm) ambulatory blood pressure (ABP) measured at baseline (1989–2008) predicted the central retinal arteriolar equivalent (CRAE) in retinal photographs obtained at follow-up (2008–2015). Systolic/diastolic hypertension thresholds were 140/90 mm Hg for CBP and 135/85 mm Hg for ABP. In multivariable-adjusted models including both baseline CBP and ABP, CRAE after 10.3 years (median) of follow-up was unrelated to CBP (P≥0.14), whereas ABP predicted CRAE narrowing (P≤0.011). Per 1-SD increment in systolic/diastolic blood pressure, the association sizes were −0.95 µm (95% confidence interval, −2.20 to 0.30)/−0.75 µm (−1.93 to 0.42) for CBP and −1.76 µm (−2.95 to −0.58)/−1.48 µm (−2.61 to −0.34) for ABP. Patients with ambulatory hypertension at baseline (17.0%) had smaller CRAE (146.5 versus 152.6 µm; P<0.001) at follow-up. CRAE was not different (P≥0.31) between true normotension (normal CBP and ABP; prevalence, 77.6%) and white-coat hypertension (elevated CBP and normal ABP, 5.4%) and between masked hypertension (normal CBP and elevated ABP, 10.2%) and hypertension (elevated CBP and ABP, 6.8%). In conclusion, the paradigm that retinal arteriolar narrowing precedes hypertension can be explained by the limitations of CBP measurement, including nonidentification of masked and white-coat hypertension.

Prevalence of Masked Hypertension and Its Association With Subclinical Cardiovascular Disease in African Americans: Results From the Jackson Heart Study

Background

Studies consisting mostly of whites have shown that the prevalence of masked hypertension differs by prehypertension status. Using data from the Jackson Heart Study, an exclusively African American population‐based cohort, we evaluated the association of masked hypertension and prehypertension with left ventricular mass index and common carotid intima media thickness.

Methods and Results

At the baseline visit, clinic blood pressure (CBP) measurement and 24‐hour ambulatory blood pressure monitoring were performed. Masked hypertension was defined as mean systolic/diastolic CBP <140/90 mm Hg and mean daytime systolic/diastolic ambulatory blood pressure ≥135/85 mm Hg. Clinic hypertension was defined as mean systolic/diastolic CBP ≥140/90 mm Hg. Normal CBP was defined as mean systolic/diastolic CBP <120/80 mm Hg and prehypertension as mean systolic/diastolic CBP 120 to 139/80 to 89 mm Hg. The analytic sample included 909 participants. Among participants with systolic/diastolic CBP <140/90 mm Hg, the prevalence of masked hypertension and prehypertension was 27.5% and 62.4%, respectively. The prevalence of masked hypertension among those with normal CBP and prehypertension was 12.9% and 36.3%, respectively. In a fully adjusted model, which included prehypertension status and antihypertensive medication use as covariates, left ventricular mass index was 7.94 g/m² lower among those without masked hypertension compared to participants with masked hypertension (P<0.001). Left ventricular mass index was also 4.77 g/m² lower among those with clinic hypertension, but this difference was not statistically significant (P=0.068). There were no significant differences in left ventricular mass index between participants with and without masked hypertension, or clinic hypertension.

Conclusions

Masked hypertension was common among African Americans with prehypertension and also normal CBP, and was associated with subclinical cardiovascular disease.

Blood Pressure Out of the Office: Its Time Has Finally Come

The diagnosis of hypertension includes measurement of blood pressure out of the office by either 24-hour ambulatory monitoring or home blood pressure monitoring. These methods have led to recognition of "white coat hypertension" (WCH) and "masked hypertension" (MH). Research in the 1930s first demonstrated that blood pressures in the office were often far different from those out of the office, at a time when there was no effective treatment. International attention was focused on another imminent world war and a highly controversial election in the United States. Hypertension was not a priority for concern. From the 1950s onward: (i) epidemiology linked hypertension to risk of cardiovascular disease, (ii) effective and safe drugs for treatment of hypertension appeared, (iii) randomized clinical trials demonstrated that drug treatment of hypertension is highly effective for prevention of cardiovascular disease, and (iv) advances in technology led to development of small, portable devices for recording blood pressure noninvasively at home or during usual activities. Accurate measurement of blood pressure in "real life" is now necessary and feasible for appropriate diagnosis and assessment of treatment. Out-of-office blood pressure measurement is emerging as the standard of care for hypertension.

The Utility of Ambulatory Blood Pressure Monitoring for Diagnosing White Coat Hypertension in Older Adults

The beneficial effect of antihypertensive medication on reducing the risk of cardiovascular disease (CVD) events is supported by data from randomized controlled trials of older adults with hypertension. However, in clinical practice, overtreatment of hypertension in older adults may lead to side effects and an increased risk of falls. The diagnosis and treatment of hypertension is primarily based on blood pressure measurements obtained in the clinic setting. Ambulatory blood pressure monitoring (ABPM) complements clinic blood pressure by measuring blood pressure in the out-of-clinic setting. ABPM can be used to identify white coat hypertension, defined as elevated clinic blood pressure and non-elevated ambulatory blood pressure. White coat hypertension is common in older adults but does not appear to be associated with an increased risk of CVD events among this population. Herein, we review the current literature on ABPM in the diagnoses of white coat hypertension in older adults, including its potential role in preventing overtreatment.

Studies comparing ambulatory blood pressure and home blood pressure on cardiovascular disease and mortality outcomes: a systematic review

Ambulatory blood pressure monitoring (ABPM) is more commonly recommended for assessing out-of-clinic blood pressure (BP) than home blood pressure monitoring (HBPM). We conducted a systematic review to examine whether ABPM or HBPM is more strongly associated with cardiovascular disease events and/or mortality. Of 1007 abstracts published through July 20, 2015, nine articles, reporting results from seven cohorts, were identified. After adjustment for BP on HBPM, BP on ABPM was associated with an increased risk of outcomes in two of four cohorts for systolic blood pressure and two of three cohorts for diastolic blood pressure. After adjustment for BP on ABPM, systolic blood pressure on HBPM was associated with outcomes in zero of three cohorts; an association was present in one of two cohorts for diastolic blood pressure on HBPM. There is a lack of strong empiric evidence supporting ABPM or HBPM over the other approach for predicting cardiovascular events or mortality.

Role of Ambulatory and Home Blood Pressure Monitoring in Clinical Practice: A Narrative Review

Hypertension, a common risk factor for cardiovascular disease, is usually diagnosed and treated based on blood pressure readings obtained in the clinic setting. Blood pressure may differ considerably when measured inside versus outside of the clinic setting. Over the past several decades, evidence has accumulated on the following 2 approaches for measuring blood pressure outside of the clinic: ambulatory blood pressure monitoring (ABPM) and home blood pressure monitoring (HBPM). Both of these methods have a stronger association with cardiovascular disease outcomes than clinic blood pressure measurement. Controversy exists about whether ABPM or HBPM is superior for estimating risk for cardiovascular disease and under what circumstances these methods should be used in clinical practice for assessing blood pressure outside of the clinic. This review describes ABPM and HBPM procedures, the blood pressure phenotypic measurements that can be ascertained, and the evidence that supports the use of each approach to measuring blood pressure outside of the clinic. It also describes barriers to the successful implementation of ABPM and HBPM in clinical practice, proposes core competencies for the conduct of these procedures, and highlights important areas for future research.

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.

[A specific questionnaire to evaluate therapeutic inertia in hypertensive patients: a pilot study]

BACKGROUND

Therapeutic inertia (TI) is a recent concept still unknown by many physicians. In chronic diseases such as hypertension, it is defined as the tendency of physicians not to increase or change antihypertensive medications when the target blood pressure is not reached. Acting on TI could improve blood pressure control in France.

METHOD

This was a single-center prospective pilot study conducted by hypertension specialist physicians at the University Cardio-Vascular Center in Lille (France). It was conducted between March and June 2011. Data was collected from 161 hypertensive patients (mean age: 61.64±11.18 years; 98 (60.9%) male; 75 secondary prevention patients). Each physician completed a questionnaire on therapeutic inertia. TI was defined as a consultation in which treatment change was indicated (systolic blood pressure [BP]≥140 and/or diastolic BP≥90mmHg in all patients), but did not occur, with absence of an adapted justification of this choice. We considered as an adapted justification: a white coat effect demonstrated by ambulatory blood pressure monitoring (ABPM) or home blood pressure monitoring; scheduled reassessment of the BP by ABPM; recent change in antihypertensive treatment (less than 4 weeks); hospitalization needed for complete evaluation of secondary causes of hypertension and a more detailed assessment of potential target organ damage in patients with grade 1 or 2 hypertension. Our study aimed to evaluate rates of TI, to identify factors associated with TI, and to test the TI questionnaire.

RESULTS

Therapeutic inertia as defined in this study occurred in 11 consultations (8.3%) of the 133 hypertensive patients having uncontrolled BP above or equal to 140 and/or 90mmHg. Significant factors associated with TI were older age (Z=2.35, P<0.05) and sleep apnea syndrome (χ(2)=8.33, P<0.05). The absence of ambulatory blood pressure monitoring before the consultation (χ(2)=4.28, 0.1>P>0.05) and the number of consultations (Z=1.92, 0.1>P>0.05) exhibited a significant trend to be associated with TI.

CONCLUSIONS

Although the rate of TI was low in our study conducted in a specialized center, a well-accepted definition of therapeutic inertia would be useful for further study. The feasibility of using the questionnaire tested with this study shows that this measurement tool could help physicians become more aware of TI, both in the hospital and primary care setting. Further multicenter studies are needed for validation.

Persistence and progression of masked hypertension: a 5-year prospective study

Objectives. To examine masked hypertension persistence over 5 years. Methods. White-collar workers were recruited from three public organizations. Blood pressure (BP) was measured using Spacelabs 90207. Manually operated BP was defined as the mean of the first three readings taken at rest. Ambulatory BP was defined as the mean of the next readings taken every 15 minutes and recorded during working hours. BP was assessed three times over 5 years. Masked hypertension was defined as manually operated BP less than 140 and less than 90 mmHg and ambulatory BP at least 135 or at least 85 mmHg. Sustained hypertension was defined as manually operated BP at least 140 or at least 90 mmHg and ambulatory BP at least 135 or at least 85 mmHg or being treated for hypertension. Results. BP measurements were obtained from 1669 participants from whom 232 had masked hypertension at baseline. Persistence of masked hypertension was 38% and 18.5%, after 3 and 5 years, respectively. Progression to sustained hypertension was 26% and 37%, after 3 and 5 years, respectively. Conclusion. Among baseline masked hypertensives, one-third progressed to sustained hypertension and about one out of five remained masked after 5 years, potentially delaying diagnosis and treatment.

Ambulatory blood pressure improves prediction of cardiovascular risk: implications for better antihypertensive management

Accurate measurement of arterial pressure is necessary for diagnosis of hypertension and for assessment of its therapy. The development and growing application of ambulatory blood pressure monitoring (ABPM) furthers these goals. Use of ABPM has defined white coat hypertension (WCH) and masked hypertension (MH), important prognostic diagnoses. ABPM categorizes blood pressure in several ways that increase accuracy for diagnosis and prediction of cardiovascular risk. Measurements of blood pressure throughout the day, at night during sleep, during the morning surge, and, in some instances selected intervals can be especially valuable for both research and clinical management. ABPM is being explored for its value in measuring pulse pressure and a derived index of arterial stiffness. ABPM has also shown to be valuable for defining the effects of antihypertensive drugs therapy. Results of such studies are crucial for advancing antihypertensive management. This review will summarize the important and emerging role of ABPM in defining risk for cardiovascular disease.

Waiting a few extra minutes before measuring blood pressure has potentially important clinical and research ramifications

Office blood pressure (BP) is recommended to be measured after 5 min of seated rest, but it may decrease for 10 min of seated rest. This study aimed to determine the change (and its clinical relevance) in brachial and central BP from 5 to 10 min of seated rest. Office brachial and central BP (measured after 5 and 10 min), left ventricular (LV) mass index, 7-day home and ambulatory BP were measured in 250 participants with treated hypertension. Office brachial and central BP were significantly lower at 10-min compared with 5-min BP (P<0.001). Seven-day home systolic BP (SBP) was significantly lower than office SBP measured at 5 min (P<0.001), but was similar to office SBP at 10 min (P=0.511). From 5 to 10 min, the percentage of participants with controlled BP increased and the percentage of participants with high central pulse pressure (PP) decreased (P<0.001). Moreover, brachial and central PP were significantly correlated with LV mass index measured at 10 min (r=0.171, P=0.006 and r=0.139, P=0.027, respectively), but not at 5 min (r=0.115, P=0.068 and r=0.084, P=0.185, respectively). BP recorded after 10 min is more representative of true BP control. These findings have relevance to appropriate diagnosis of hypertension and design of clinical trials.

Local and systemic cardiovascular effects from monochromatic infrared therapy in patients with knee osteoarthritis: a double-blind, randomized, placebo-controlled study

Infrared (IR) therapy is used for pain relief in patients with knee osteoarthritis (OA). However, IR's effects on the cardiovascular system remain uncertain. Therefore, we investigated the local and systemic cardiovascular effects of monochromatic IR therapy on patients with knee OA in a double-blind, randomized, placebo-controlled study. Seventy-one subjects with knee OA received one session of 40 min of active or placebo monochromatic IR treatment (with power output of 6.24 W, wavelength of 890 nm, power density of 34.7 mW/cm² for 40 min, total energy of 41.6 J/cm² per knee per session) over the knee joints. Heart rate, blood pressure, and knee arterial blood flow velocity were periodically assessed at the baseline, during, and after treatment. Data were analyzed by repeated-measure analysis of covariance. Compared to baseline, there were no statistically significant group x time interaction effects between the 2 groups for heart rate (P = 0.160), blood pressure (systolic blood pressure: P = 0.861; diastolic blood pressure: P = 0.757), or mean arterial blood flow velocity (P = 0.769) in follow-up assessments. The present study revealed that although there was no increase of knee arterial blood flow velocity, monochromatic IR therapy produced no detrimental systemic cardiovascular effects.

Requirements for professional office blood pressure monitors

For more than half a century measurement of blood pressure in the doctor's office using a mercury sphygmomanometer and the auscultatory method has been the cornerstone for hypertension management. However, due to the environmental and service issues mercury devices will not be available in the near future. As the mercury sphygmomanometer is being progressively eliminated from clinical use, it is being replaced by a variety of devices, which may not have been validated. This change in the practice of measurement may have an unpredictable impact on the threshold levels used for the diagnosis of hypertension and may also influence the management of hypertension. This expert document provides (i) information on the current availability of technologies and devices with potential for professional use (oscillometric, hybrid, aneroid and mercury devices) and the advantages and limitations of each one of them, and (ii) guidance on the requirements and selection of mercury-free blood pressure monitors for professional use. With the increasing use of automated oscillometric devices it is likely that the auscultatory technique will soon become redundant. However, consideration will be given to some of the technical aspects of the oscillometric technique and to the educational aspects of auscultation that may make it premature to abandon the technique altogether.

Masked hypertension and prehypertension: diagnostic overlap and interrelationships with left ventricular mass: the Masked Hypertension Study

BACKGROUND

Masked hypertension (MHT) and prehypertension (PHT) are both associated with an increase in cardiovascular disease (CVD) risk, relative to sustained normotension. This study examined the diagnostic overlap between MHT and PHT, and their interrelationships with left ventricular (LV) mass index (LVMI), a marker of cardiovascular end-organ damage.

METHODS

A research nurse performed three manual clinic blood pressure (CBP) measurements on three occasions over a 3-week period (total of nine readings, which were averaged) in 813 participants without treated hypertension from the Masked Hypertension Study, an ongoing worksite-based, population study. Twenty-four-hour ambulatory blood pressure (ABP) was assessed by using a SpaceLabs 90207 monitor. LVMI was determined by echocardiography in 784 (96.4%) participants.

RESULTS

Of the 813 participants, 769 (94.6%) had normal CBP levels (<140/90 mm Hg). One hundred and seventeen (15.2%) participants with normal CBP had MHT (normal CBP and mean awake ABP ≥135/85 mm Hg) and 287 (37.3%) had PHT (mean CBP 120-139/80-89 mm Hg). 83.8% of MHT participants had PHT and 34.1% of PHT participants had MHT. MHT was infrequent (3.9%) when CBP was optimal (<120/80 mm Hg). After adjusting for age, gender, body mass index (BMI), race/ethnicity, history of high cholesterol, history of diabetes, current smoking, family history of hypertension, and physical activity, compared with optimal CBP with MHT participants, LVMI was significantly greater in PHT without MHT participants and in PHT with MHT participants.

CONCLUSIONS

In this community sample, there was substantial diagnostic overlap between MHT and PHT. The diagnosis of MHT using an ABP monitor may not be warranted for individuals with optimal CBP.

[Measurement of blood pressure in consultation and automated mesurement (BPTru(®)) to evaluate the white coat effect]

BACKGROUND AND OBJECTIVE

White coat effect (WCE) is one of the main bias that can affect office blood pressure (BP) measurement. Therefore, it is a factor must be considered in hypertensives to avoid mistakes in diagnosis and/or treatment. Employment of automated office BP (AOBP) devices could diminish that effect.

METHODS

Two studies were designed with the objective of evaluating differences between routinely office and AOBP measurements. WCE was also assessed. First, the TRUE-ESP study included normotensive and hypertensive patients attending specialized consultations at Cardiology, Nephrology, Internal Medicine, Endocrinology and Family Practice. Second, the TRUE-HTA study included hypertensives attending a protocoled Hypertension Unit, with a trained staff.

RESULTS

TRUE-ESP study included 300 patients, 76% being hypertensives. A significant difference between office BP and AOBP measurement (SBP/DBP 9.8±11.6/3.4±7.9 mmHg, P<.001) was observed. Percentage of patients gathering WCE criteria was 27.7%. TRUE-HTA study included 101 hypertensive patients. A significant difference between office BP and AOBP measurement (SBP/DBP 5.7±9.3/2.1±5.3 mmHg, P<.001) and activity period-ABPM (SBP/DBP 8.5±6.7/3.5±2.5 mmHg, P<.001) was observed. Percentage of WCE patients was 32.1%.

CONCLUSIONS

Use of AOBP devices can contribute to decrease WCE and to improve accuracy of office BP measurement.

Home blood pressure for the management of hypertension: will it become the new standard of practice?

Accurate identification of hypertension is crucial for the prevention of cardiovascular disease. Home blood pressure monitoring (HBPM) provides superior prediction of cardiovascular disease, compared with clinic pressures. HBPM can be a valuable resource for the effective treatment of hypertension, when combined with other modalities used to improve patient education, lifestyle enhancement, adherence to medication and reduction of unnecessary clinic visits. In some developed nations, more than half of households with a hypertensive patient have a device for HBPM. The use of HBPM by patients and the acceptance of HBPM measurements by providers is increasing. The long-term effectiveness of HBPM, combined with telemetry for disease prevention, is promising. More research is still needed to establish its full value. It is predicted that HBPM has definite potential for more effective strategies to control hypertension and reduce the need for on-site clinical care.

Comparative assessment of four blood pressure measurement methods in hypertensives

INTRODUCTION

Discordance between blood pressure (BP) measurement methods can occur and create ambiguity. New automated office BP monitors (AOBPs) are widely available, but their role is presently unclear. The objectives of this study are to quantify concordance among BP measurement methods and to define the diagnostic sensitivity, specificity, and predictive value of AOBPs in a population of hypertensive patients.

METHODS

The office mercury sphygmomanometer, the AOBP, an ambulatory BP monitor (ABPM), and home self-measurement with an automatic device were compared in a randomized, crossover study. BP averages and achievement of therapeutic goals were defined. Comparisons and agreement tests were performed. Diagnostic indices were calculated for the AOBP.

RESULTS

A total of 101 patients were enrolled. Average BP results were similar between measurement methods with the exception of daytime ABPM, which was significantly higher; figures are mean ± standard deviation (SD): sphygmomanometer, 129.9 ± 13.7/80.9 ± 9.3 mm Hg; AOBP, 128.4 ± 13.9/80.0 ± 9.4 mm Hg; 24-hour ABPM, 131.4 ± 11.7/78.7 ± 9.7 mm Hg; day ABPM, 135.5 ± 11.4/82.0 ± 11.9 mm Hg; home self-measurement, 131.0 ± 14.3/82.5 ± 8.2 mm Hg. Discordance in the achievement of therapeutic goals was observed in 58 patients, with only 26 cases being explained by masked hypertension or "white coat syndrome" according to all measurements. Disagreement was greater when office methods were compared with ambulatory methods.

CONCLUSIONS

This study shows that the 4 measurement strategies provide similar average BP estimates but generate many discordant results. The AOBP device can be very valuable as a replacement for the sphygmomanometer.

Magnitude of the white-coat effect in the community pharmacy setting: the MEPAFAR study

BACKGROUND

There is little information regarding the community pharmacy blood pressure (CPBP) measurement method and their differences with home (HBP) or ambulatory BP (ABP). The aim of this study was to measure such differences and their variation over successive visits.

METHOD

Cross-sectional study carried out in eight pharmacies in Gran Canaria (Spain). The study included 169 treated hypertensive patients. BP was measured at the pharmacy (four visits), at HBP (4 days) and 24-h ABP monitoring. We defined pharmacy white-coat effect (PWCE) as differences between CPBP and HBP (home PWCE) or daytime ABP (ambulatory PWCE).

RESULTS

The overall (pooled values for all visits) ambulatory PWCE was not significantly different from zero for systolic BP (SBP) (-0.4 mm Hg (95% confidence interval (CI): -1.8 to 1.1)), but greater than zero for diastolic BP (DBP) (3.4 mm Hg (95% CI: 2.3 to 4.6)). The overall home PWCE was not significantly different from zero, both for SBP (1.2 mm Hg (95% CI: -0.1 to 2.6)) and DBP (0.1 mm Hg (95% CI: -0.7 to 1.0)). The ambulatory and home PWCE on the first visit were greater than zero (P < 0.001) (SBP/DBP): 3.5/4.8 and 1.9/1.5 mm Hg, respectively; but showed important reductions at the second visit and became not significantly different from zero, except the ambulatory PWCE in DBP, which persisted until the last visit.

CONCLUSION

The trend in the PWCE decreased over the successive visits to the pharmacy. Only the ambulatory PWCE in DBP proved to be statistically greater than zero after the second visit. Repeated CPBP measurements could be a useful alternative to assess the response to antihypertensive treatment.

Tolerability of the Oscar 2 ambulatory blood pressure monitor among research participants: a cross-sectional repeated measures study

BACKGROUND

Ambulatory blood pressure monitoring (ABPM) is increasingly used to measure blood pressure (BP) in research studies. We examined ease of use, comfort, degree of disturbance, reported adverse effects, factors associated with poor tolerability, and association of poor tolerability with data acquisition of 24-hour ABPM using the Oscar 2 monitor in the research setting.

METHODS

Sixty adults participating in a research study of people with a history of borderline clinic BP reported on their experience with ABPM on two occasions one week apart. Poor tolerability was operationalized as an overall score at or above the 75th percentile using responses to questions adapted from a previously developed questionnaire. In addition to descriptive statistics (means for responses to Likert-scaled "0 to 10" questions and proportions for Yes/No questions), we examined reproducibility of poor tolerability as well as associations with poor tolerability and whether poor tolerability was associated with removal of the monitor or inadequate number of BP measurements.

RESULTS

The mean ambulatory BP of participants by an initial ABPM session was 148/87 mm Hg. After wearing the monitor the first time, the degree to which the monitor was felt to be cumbersome ranged from a mean of 3.0 to 3.8, depending on whether at work, home, driving, or other times. The most bother was interference with normal sleeping pattern (mean 4.2). Wearers found the monitor straightforward to use (mean 7.5). Nearly 67% reported that the monitor woke them after falling asleep, and 8.6% removed it at some point during the night. Reported adverse effects included pain (32%), skin irritation (37%), and bruising (7%). Those categorized as having poor tolerability (kappa = 0.5 between sessions, p = 0.0003) were more likely to report being in fair/poor health (75% vs 22%, p = 0.01) and have elevated 24-hour BP average (systolic: 28% vs 17%, p = 0.56; diastolic: 30% vs 17%, p = 0.37). They were also more likely to remove the monitor and have inadequate numbers of measurements.

CONCLUSIONS

The Oscar 2 ABPM device is straightforward to use but can interfere with sleep. Commonly reported adverse effects include pain, skin irritation, and bruising. Those who tolerate the monitor poorly are more likely to report being in fair or poor health and to remove it, particularly at night.

Conventional versus automated measurement of blood pressure in primary care patients with systolic hypertension: randomised parallel design controlled trial

OBJECTIVE

To compare the quality and accuracy of manual office blood pressure and automated office blood pressure using the awake ambulatory blood pressure as a gold standard.

DESIGN

Multi-site cluster randomised controlled trial.

SETTING

Primary care practices in five cities in eastern Canada.

PARTICIPANTS

555 patients with systolic hypertension and no serious comorbidities under the care of 88 primary care physicians in 67 practices in the community.

INTERVENTIONS

Practices were randomly allocated to either ongoing use of manual office blood pressure (control group) or automated office blood pressure (intervention group) using the BpTRU device. The last routine manual office blood pressure (mm Hg) was obtained from each patient's medical record before enrollment. Office blood pressure readings were compared before and after enrollment in the intervention and control groups; all readings were also compared with the awake ambulatory blood pressure.

MAIN OUTCOME MEASURE

Difference in systolic blood pressure between awake ambulatory blood pressure minus automated office blood pressure and awake ambulatory blood pressure minus manual office blood pressure.

RESULTS

Cluster randomisation allocated 31 practices (252 patients) to manual office blood pressure and 36 practices (303 patients) to automated office blood pressure measurement. The most recent routine manual office blood pressure (149.5 (SD 10.8)/81.4 (8.3)) was higher than automated office blood pressure (135.6 (17.3)/77.7 (10.9)) (P < 0.001). In the control group, routine manual office blood pressure before enrollment (149.9 (10.7)/81.8 (8.5)) was reduced to 141.4 (14.6)/80.2 (9.5) after enrollment (P < 0.001/P = 0.01), but the reduction in the intervention group from manual office to automated office blood pressure was significantly greater (P < 0.001/P = 0.02). On the first study visit after enrollment, the estimated mean difference for the intervention group between the awake ambulatory systolic/diastolic blood pressure and automated office blood pressure (-2.3 (95% confidence interval -0.31 to -4.3)/-3.3 (-2.7 to -4.4)) was less (P = 0.006/P = 0.26) than the difference in the control group between the awake ambulatory blood pressure and the manual office blood pressure (-6.5 (-4.3 to -8.6)/-4.3 (-2.9 to -5.8)). Systolic/diastolic automated office blood pressure showed a stronger (P < 0.001) within group correlation (r = 0.34/r = 0.56) with awake ambulatory blood pressure after enrollment compared with manual office blood pressure versus awake ambulatory blood pressure before enrollment (r = 0.10/r = 0.40); the mean difference in r was 0.24 (0.12 to 0.36)/0.16 (0.07 to 0.25)). The between group correlation comparing diastolic automated office blood pressure and awake ambulatory blood pressure (r = 0.56) was stronger (P < 0.001) than that for manual office blood pressure versus awake ambulatory blood pressure (r = 0.30); the mean difference in r was 0.26 (0.09 to 0.41). Digit preference with readings ending in zero was substantially reduced by use of automated office blood pressure.

CONCLUSION

In compliant, otherwise healthy, primary care patients with systolic hypertension, introduction of automated office blood pressure into routine primary care significantly reduced the white coat response compared with the ongoing use of manual office blood pressure measurement. The quality and accuracy of automated office blood pressure in relation to the awake ambulatory blood pressure was also significantly better when compared with manual office blood pressure. Trial registration Clinical trials NCT 00214053.

The role of blood pressure variability in misdiagnosed clinic hypertension

Blood pressure (BP) assessment may be vulnerable to bias by increased BP variability. Uncertainty in determining BP control is inherent to the clinic setting. We analyzed a registry of 3949 patients referred for ambulatory BP monitoring. The difference between clinic and ambulatory readings was plotted against ambulatory BP variability, assessed by standard deviation. In addition, BP variability of patients with clinic and awake ambulatory hypertension was compared with that of patients with controlled BP and sustained hypertension, respectively. The average clinic-ambulatory systolic BP difference was 5 ± 17/3 ± 9 mm  Hg. Patients with >10-mm  Hg systolic difference had higher systolic ambulatory BP standard deviation (14.9 ± 4.2 mm  Hg) compared to patients with a difference of 0 to 10-mm  Hg (standard deviation 12.5 ± 3.7 mm  Hg). Patients with masking (negative clinic-ambulatory BP difference) also had comparatively higher standard deviation (14.4 ± 4.9 mm  Hg P<0.0001). Greater ambulatory BP variability carried increased risk for both false diagnosis of hypertension (odds ratio (OR): 2.09, 95% confidence interval (CI): 1.58-2.76), and missed clinic diagnosis of hypertension (OR: 1.86, 95% confidence interval: 1.48-2.33). The former was more striking in women, in whom high variability carried greater odds for false diagnosis of hypertension (OR: 2.76, 95% confidence interval: 1.96-3.89). Thus, clinic misjudgment of BP control may stem in part from high BP variability. Women with high BP variability are more susceptible to hypertension misdiagnosis. It is possible that high BP variability contributes to the increased cardiovascular risk related to both masked hypertension and white coat hypertension.

Causal mechanisms of masked hypertension: socio-psychological aspects

The contribution of Dr Thomas Pickering's study to the measurement of blood pressure (BP) is the defining aspect of his academic career and achievement - narrowly defined. In this regard, two important areas characterized his study as it relates to masked hypertension. First, he introduced the term, masked hypertension, to replace the rather inappropriate term 'reverse white-coat hypertension' and 'white-coat normotension'; thus drawing attention to the fact that these patients are genuinely hypertensive by ambulatory BP but were missed by normal office BP. More importantly, he rightly maintained that masked hypertension is a true continuum of sustained hypertension rather than an aberrant measurement artifact. Second, is his pivotal study on the important role of psychosocial factors as a potential mechanism for the development of masked hypertension. In this regard, he explained masked hypertension as a conditioned response to anxiety in office settings, and highlighted the role that diagnostic labeling plays in its development. His view of masked hypertension is that of a continuum from prehypertension (based on office BP measurement) to masked hypertension (based on ambulatory BP) and finally to sustained hypertension (based on both office and ambulatory BP). He strongly believes that it is the prehypertensive patients who progress to masked hypertension. Subsequently, patients who are prehypertensive should be screened for masked hypertension and treated. In this manuscript, we summarize his study as it relates to the definition of masked hypertension, the psychosocial characteristics, mechanisms and its clinical relevance.

From pioneering to implementing automated blood pressure measurement in clinical practice: Thomas Pickering's legacy

Thomas G. Pickering spent most of his scientific career in carrying out research on clinical hypertension and blood pressure (BP) measurement. In our review of Pickering's seminal work, we first focused on white-coat hypertension and masked hypertension, two terms that he had introduced. Next, we highlighted the early publications of Pickering on diurnal BP variability and on the clinical application of self-measured BP. Pickering's work inspired many investigators worldwide and constituted a solid basis for further research. Pickering's original ideas led to algorithms for risk stratification involving white-coat hypertension and masked hypertension, diurnal BP variability, and self-measured BP. Recent studies validated Pickering's observations in terms of cardiovascular outcome and bridged the path from concept to application in clinical practice.