Evaluation of Criteria to Detect Masked Hypertension

When and how to use ambulatory blood pressure monitoring and home blood pressure monitoring for managing hypertension

Many individuals have different blood pressure (BP) values in the office setting compared to that outside the office setting. Therefore, confirming hypertension based on office BP (OBP) measurement alone can lead to misdiagnosis and mistreatment. The limitations of OBP measurement have led to the complementary use of out-of-office BP measurements, including 24-hour ambulatory blood pressure monitoring (ABPM) and home blood pressure monitoring (HBPM). This review aims to describe when and how ABPM or HBPM can be used to accurately diagnose and treat hypertension. Both methods should be performed using validated automated oscillometric devices. To minimize user errors, ABPM should be performed using standard techniques, whereas HBPM requires patient education regarding proper BP measurements. ABPM provides short-term comprehensive information on BP, including daytime, nighttime, morning, and 24-h BP. Therefore, ABPM is recommended for the initial diagnosis of hypertension, assessment of BP phenotypes and circadian patterns, and detection of nocturnal hypertension, Furthermore, ABPM plays a critical role in confirming true resistant hypertension thereby excluding pseudo-resistant hypertension. However, it is not suitable for long-term follow-up of patients with hypertension. In contrast, HBPM involves multiple BP readings taken at specific times during the day and evening over a long period. Therefore, HBPM is recommended for diagnosing hypertension and assessing BP phenotypes. However, this method has limitations in measuring nocturnal BP and circadian BP patterns. HBPM is preferred over ABPM for the long-term follow-up of patients with hypertension. This approach improves patient adherence to treatment and ultimately enhances the rate of control of hypertension. Additionally, both methods play an important role in diagnosing and treating white coat hypertension during pregnancy. Consequently, out-of-office BP measurement is essential to prevent the misdiagnosis and mistreatment of hypertension. However, these two methods offer different information regarding the BP status of an individual, and they indeed show discrepancies in the diagnosis of hypertensive phenotypes. Therefore, it is crucial to understand the advantages and limitations of both ABPM and HBPM to ensure their appropriate use in clinical practice.

Use of Different Blood Pressure Thresholds to Reduce the Number of Home Blood Pressure Monitoring Days Needed for Detecting Hypertension

BACKGROUND

Home blood pressure (BP) monitoring over a 7-day period is recommended to confirm the diagnosis of hypertension.

METHODS

We determined upper and lower home BP thresholds with >90% positive predictive value and >90% negative predictive value using 1 to 6 days of monitoring to identify high home BP (systolic BP ≥130 mm Hg or diastolic BP ≥80 mm Hg) based on 7 days of home BP monitoring. The sample included 361 adults from the Improving the Detection of Hypertension Study who were not taking antihypertensive medication. We used two 7-day periods, at least 3 days apart, the first being a sampling period and the second a reference period. For each number of days in the sampling period, we determined the percentage of participants who had a high likelihood of having (>90% positive predictive value) or not having (>90% negative predictive value) high BP and would not need to continue home BP monitoring. Only the participants in an uncertain category (ie, positive predictive value ≤90% and negative predictive value ≤90%) after each day were carried forward to the next day of home BP monitoring.

RESULTS

Of the 361 participants (mean [SD] age of 41.3 [13.2] years; 60.4% women), 38.0% had high home BP during the reference period. There were 63.7%, 17.1%, 10.5%, 3.3%, 3.6%, and 1.4% participants who would not need to continue after 1, 2, 3, 4, 5, and 6 days of monitoring.

CONCLUSIONS

In most people, high home BP can be identified or excluded with a high degree of confidence with 3 days or less of monitoring.

Impact of Asleep and 24-Hour Blood Pressure Data on the Prevalence of Masked Hypertension by Race/Ethnicity

BACKGROUND

We pooled ambulatory blood pressure monitoring data from 5 US studies, including the Jackson Heart Study (JHS), the Coronary Artery Risk Development in Young Adults (CARDIA) study, the Masked Hypertension Study, the Improving the Detection of Hypertension Study, and the North Carolina Masked Hypertension Study. Using a cross-sectional study design, we estimated differences in the prevalence of masked hypertension by race/ethnicity when out-of-office blood pressure (BP) included awake, asleep, and 24-hour BP vs. awake BP alone.

METHODS

We restricted the analyses to participants with office systolic BP (SBP) <130 mm Hg and diastolic BP (DBP) <80 mm Hg. High awake BP was defined as mean SBP/DBP ≥130/80 mm Hg, high asleep BP as mean SBP/DBP ≥110/65 mm Hg, and high 24-hour BP as mean SBP/DBP ≥125/75 mm Hg.

RESULTS

Among participants not taking antihypertensive medication (n = 1,292), the prevalence of masked hypertension with out-of-office BP defined by awake BP alone or by awake, asleep, or 24-hour BP was 34.5% and 48.7%, respectively, among non-Hispanic White, 39.7% and 67.6% among non-Hispanic Black, and 19.4% and 35.1% among Hispanic participants. After multivariable adjustment, non-Hispanic Black were more likely than non-Hispanic White participants to have masked hypertension by asleep or 24-hour BP but not awake BP (adjusted odds ratio [OR] 2.14 95% confidence interval [CI] 1.45-3.15) and by asleep or 24-hour BP and awake BP (OR 1.61; 95% CI 1.12-2.32) vs. not having masked hypertension.

CONCLUSIONS

Assessing asleep and 24-hour BP measures increases the prevalence of masked hypertension more among non-Hispanic Black vs. non-Hispanic White individuals.

Predicting Out-of-Office Blood Pressure in a Diverse US Population

BACKGROUND

The PRedicting Out-of-OFfice Blood Pressure (PROOF-BP) algorithm accurately predicted out-of-office blood pressure (BP) among adults with suspected high BP in the United Kingdom and Canada. We tested the accuracy of PROOF-BP in a diverse US population and evaluated a newly developed US-specific algorithm (PROOF-BP-US).

METHODS

Adults with ≥2 office BP readings and ≥10 awake BP readings on 24-hour ambulatory BP monitoring from 4 pooled US studies were included. We compared mean awake BP with predicted out-of-office BP using PROOF-BP and PROOF-BP-US. Our primary outcomes were hypertensive out-of-office systolic BP (SBP) ≥130 mm Hg and diastolic BP (DBP) ≥80 mm Hg.

RESULTS

We included 3,058 adults, mean (SD) age was 52.0 (11.9) years, 38% were male, and 54% were Black. The area under the receiver-operator characteristic (AUROC) curve (95% confidence interval) for hypertensive out-of-office SBP was 0.81 (0.79-0.82) and DBP was 0.76 (0.74-0.78) for PROOF-BP. For PROOF-BP-US, the AUROC curve for hypertensive out-of-office SBP was 0.82 (0.81-0.83) and for DBP was 0.81 (0.79-0.83). The optimal predicted out-of-office BP ranges for out-of-office BP measurement referral were 120-134/75-84 mm Hg for PROOF-BP and 125-134/75-84 mm Hg for PROOF-BP-US. The 2017 American College of Cardiology/American Heart Association BP guideline (referral range 130-159/80-99 mm Hg) would refer 93.1% of adults not taking antihypertensive medications with office BP ≥130/80 mm Hg in the National Health and Nutrition Examination Survey for out-of-office BP measurement, compared with 53.1% using PROOF-BP and 46.8% using PROOF-BP-US.

CONCLUSIONS

PROOF-BP and PROOF-BP-US accurately predicted out-of-office hypertension in a diverse sample of US adults.

Screening for Hypertension in Adults: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Hypertension is a major risk factor for cardiovascular disease and can be modified through lifestyle and pharmacological interventions to reduce cardiovascular events and mortality.

OBJECTIVE

To systematically review the benefits and harms of screening and confirmatory blood pressure measurements in adults, to inform the US Preventive Services Task Force.

DATA SOURCES

MEDLINE, PubMed, Cochrane Collaboration Central Registry of Controlled Trials, and CINAHL; surveillance through March 26, 2021.

STUDY SELECTION

Randomized clinical trials (RCTs) and nonrandomized controlled intervention studies for effectiveness of screening; accuracy studies for screening and confirmatory measurements (ambulatory blood pressure monitoring as the reference standard); RCTs and nonrandomized controlled intervention studies and observational studies for harms of screening and confirmation.

DATA EXTRACTION AND SYNTHESIS

Independent critical appraisal and data abstraction; meta-analyses and qualitative syntheses.

MAIN OUTCOMES AND MEASURES

Mortality; cardiovascular events; quality of life; sensitivity, specificity, positive and negative predictive values; harms of screening.

RESULTS

A total of 52 studies (N = 215 534) were identified in this systematic review. One cluster RCT (n = 140 642) of a multicomponent intervention including hypertension screening reported fewer annual cardiovascular-related hospital admissions for cardiovascular disease in the intervention group compared with the control group (difference, 3.02 per 1000 people; rate ratio, 0.91 [95% CI, 0.86-0.97]). Meta-analysis of 15 studies (n = 11 309) of initial office-based blood pressure screening showed a pooled sensitivity of 0.54 (95% CI, 0.37-0.70) and specificity of 0.90 (95% CI, 0.84-0.95), with considerable clinical and statistical heterogeneity. Eighteen studies (n = 57 128) of various confirmatory blood pressure measurement modalities were heterogeneous. Meta-analysis of 8 office-based confirmation studies (n = 53 183) showed a pooled sensitivity of 0.80 (95% CI, 0.68-0.88) and specificity of 0.55 (95% CI, 0.42-0.66). Meta-analysis of 4 home-based confirmation studies (n = 1001) showed a pooled sensitivity of 0.84 (95% CI, 0.76-0.90) and a specificity of 0.60 (95% CI, 0.48-0.71). Thirteen studies (n = 5150) suggested that screening was associated with no decrement in quality of life or psychological distress; evidence on absenteeism was mixed. Ambulatory blood pressure measurement was associated with temporary sleep disturbance and bruising.

CONCLUSIONS AND RELEVANCE

Screening using office-based blood pressure measurement had major accuracy limitations, including misdiagnosis; however, direct harms of measurement were minimal. Research is needed to determine optimal screening and confirmatory algorithms for clinical practice.

Diagnostic performance of clinic and home blood pressure measurements compared with ambulatory blood pressure: a systematic review and meta-analysis

BACKGROUND

Clinic blood pressure measurement (CBPM) is currently the most commonly used form of screening for hypertension, however it might have a problem detecting white coat hypertension (WCHT) and masked hypertension (MHT). Home blood pressure measurement (HBPM) may be an alternative, but its diagnostic performance is inconclusive relative to CBPM. Therefore, this systematic review aimed to estimate the performance of CBPM and HBPM compared with ambulatory blood pressure measurement(ABPM) and to pool prevalence of WCHT and MHT.

METHODS

Medline, Scopus, Cochrane Central Register of Controlled Trials and WHO's International Clinical Trials Registry Platform databases were searched up to 23rd January 2020. Studies having diagnostic tests as CBPM or HBPM with reference standard as ABPM, reporting sensitivity and specificity of both tests and/or proportion of WCHT or MHT were eligible. Diagnostic performance of CBPM and HBPM were pooled using bivariate mixed-effect regression model. Random effect model was applied to pool prevalence of WCHT and MHT.

RESULTS

Fifty-eight studies were eligible. Pooled sensitivity, specificity, and diagnostic odds ratio (DOR) of CBPM, when using 24-h ABPM as the reference standard, were 74% (95% CI: 65-82%), 79% (95% CI: 69%, 87%), and 11.11 (95% CI: 6.82, 14.20), respectively. Pooled prevalence of WCHT and MHT were 0.24 (95% CI 0.19, 0.29) and 0.29 (95% CI 0.20, 0.38). Pooled sensitivity, specificity, and DOR of HBPM were 71% (95% CI 61%, 80%), 82% (95% CI 77%, 87%), and 11.60 (95% CI 8.98, 15.13), respectively.

CONCLUSIONS

Diagnostic performances of HBPM were slightly higher than CBPM. However, the prevalence of MHT was high in negative CBPM and some persons with normal HBPM had elevated BP from 24-h ABPM. Therefore, ABPM is still necessary for confirming the diagnosis of HT.

Using Predicted Atherosclerotic Cardiovascular Disease Risk for Discrimination of Awake or Nocturnal Hypertension

BACKGROUND

Several atherosclerotic cardiovascular disease (ASCVD) risk factors are associated with awake and nocturnal hypertension.

METHODS

We assessed the association between a composite ASCVD risk score and awake or nocturnal hypertension using data from participants aged 40-79 years who completed ambulatory blood pressure monitoring at the Year 30 Coronary Artery Risk Development in Young Adults study exam in 2015-2016 (n = 716) and the baseline Jackson Heart Study exam in 2000-2004 (n = 770). Ten-year predicted ASCVD risk was calculated using the Pooled Cohort risk equations. Awake hypertension was defined as mean awake systolic blood pressure (SBP) ≥135 mm Hg or diastolic blood pressure (DBP) ≥85 mm Hg and nocturnal hypertension was defined as mean asleep SBP ≥120 mm Hg or DBP ≥70 mm Hg.

RESULTS

Among participants with a 10-year predicted ASCVD risk <5%, 5% to <7.5%, 7.5% to <10%, and ≥10%, the prevalence of awake or nocturnal hypertension as a composite outcome was 29.5%, 47.8%, 62.2%, and 69.7%, respectively. After multivariable adjustment, higher ASCVD risk was associated with higher prevalence ratios for awake or nocturnal hypertension among participants with clinic-measured SBP/DBP <130/85 mm Hg but not ≥130/85 mm Hg. The C-statistic for discriminating between participants with vs. without awake or nocturnal hypertension was 0.012 (95% confidence interval 0.003, 0.016) higher when comparing a model with ASCVD risk and clinic-measured blood pressure (BP) together vs. clinic-measured BP without ASCVD risk.

CONCLUSIONS

Using 10-year predicted ASCVD risk in conjunction with clinic BP improves discrimination between individuals with and without awake or nocturnal hypertension.

Short-Term Reproducibility of Masked Hypertension Among Adults Without Office Hypertension

The 2017 American College of Cardiology/American Heart Association blood pressure (BP) Hypertension Clinical Practice Guidelines recommends ambulatory BP monitoring to detect masked hypertension. Data on the short-term reproducibility of masked hypertension are scarce. The IDH study (Improving the Detection of Hypertension) enrolled 408 adults not taking antihypertensive medication from 2011 to 2013. Office BP and 24-hour ambulatory BP monitoring were performed on 2 occasions, a median of 29 days apart. After excluding participants with office hypertension (mean systolic BP ≥130 mm Hg or diastolic BP ≥80 mm Hg), the analytical sample included 254 participants. Using the κ statistic, we evaluated the reproducibility of masked awake hypertension (awake systolic/diastolic BP ≥130/80 mm Hg) defined by the 2017 BP guideline thresholds, as well as masked 24-hour (24-hour systolic/diastolic BP ≥125/75 mm Hg), masked asleep (asleep systolic/diastolic BP ≥110/65 mm Hg), and any masked hypertension (high awake, 24-hour, and asleep BP). The mean (SD) age of participants was 38.0 (12.3) years and 65.7% were female. Based on the first and second ambulatory BP recordings, 24.0% and 26.4% of participants, respectively, had masked awake hypertension. The κ statistic (95% CI) was 0.50 (0.38-0.62) for masked awake, 0.57 (0.46-0.69) for masked 24-hour, 0.57 (0.47-0.68) for masked asleep, and 0.58 (0.47-0.68) for any masked hypertension. Clinicians should consider the moderate short-term reproducibility of masked hypertension when interpreting the results from a single ambulatory BP recording.

Assessment of cardiometabolic risk factors in various phenotypes of masked hypertension

Aim. To assess the relationship of cardiometabolic risk factors in patients with various phenotypes of masked hypertension (MH).

Material and methods. The study included 207 men with a median age of 34,6 years [32,3; 36,3] being systematically stressed. All examined patients had normal clinical blood pressure (BP), and there was no history of its increase. We conducted 24-hour ambulatory blood pressure monitoring (ABPM), carotid duplex scan with determination of the intima- media thickness (IMT). The levels of total cholesterol (TC), low (LDLC) and high-density lipoprotein cholesterol (HDL-C), triglycerides (TG) were determined. Body mass index, visceral adiposity index, lipid accumulation product index and waist-to-height ratio were calculated. We performed clustering of ABPM data, calculated the odds ratio of association between cardiometabolic risk factors and certain MH phenotypes.

Results. MH was diagnosed in 142 (68,6%) patients examined, divided into 3 clusters: systolic-diastolic — SDMH (50,7%), isolated systolic — ISMH (27,5%) and isolated diastolic — IDMH (21,8%). Impaired lipid metabolism, visceral adiposity, IMT increase and atherosclerotic plaques were more often recorded in patients with SDMH and IDMH. The levels of TC, LDL-C and IMT were highest in individuals with IDMH. Odds ratio analysis indicated significant associations of SDMH and IDMH phenotypes with indicators of visceral adiposity, IMT, TG, TC, LDL-C and TG/HDL-Cl.

Conclusion. Clustering of ABPM data in individuals with MH and comparing related phenotypes with cardiometabolic risk factors complements their clinical and functional characteristics and can be a useful tool for improving customized prevention and therapy programs.

[Machine Learning Methods in Assessing the Risks of Target Organ Damage in Masked Hypertension]

Aim To develop models for predicting the risk of target organs damage (TOD) in different phenotypes of "masked" arterial hypertension (MAH) based on methods of machine learning (ML).Material and methods A retrospective cohort analysis was performed for 284 clinical records of patients (261 males, 23 females; median age, 38 years). Group 1 included 125 patients with grade 1-2 arterial hypertension (AH) and low or moderate risk; group 2 included 159 subjects with normal "office" blood pressure (BP) exposed to chronic professional stress. The 24-h BP monitoring (24-h BPM) and ultrasound examination of the heart and carotid arteries were performed; glomerular filtration rate (GFR) was estimated using the СКD-EPI formula. MAH was phenotyped by clustering 24-h BPM data, and the risk of TOD was predicted by analysis of odd ratios (OR) and with the ML methods, random forest (RF) and artificial neural networks (ANN). Data were analyzed using the R language in the RStudio environment.Results According to results of the 24-h BPM and cluster analysis, 121 (76.1 %) subjects of group 2 had MAH. The MAH phenotypes were identified as follows: systolic-diastolic (SDMAH) (43.8 %); isolated systolic (ISMAH) (35.5 %), and isolated diastolic (IDMAH) (20.7%). As compared to stable AH, subjects with different MAH phenotypes showed both increases and decreases in individual 24-h BPM indexes. Thus, in subjects with IDMAH, mean 24-h values of systolic and diastolic BP were significantly lower than with AH while in SDMAH, they were considerably higher. The OR analysis demonstrated that odds of differently located TOD were associated with definite MAH phenotypes. With that, ISMAH was associated with the highest risk of glomerular hyperfiltration; IDMAH was associated with reduced GFR and vascular remodeling; and SDMAH was associated with left ventricular myocardial hypertrophy. The developed models for predicting the risk of TOD based on the RF and ANN methods showed a high accuracy, which was provided by multistep procedures of selecting the predictors and cross-validation.Conclusion Modern ML technologies enhance the risk stratification of patients with different clinical variants of AH.

Effects of white-coat, masked and sustained hypertension on coronary artery stenosis and cardiac arrhythmia

This study aimed to investigate whether hypertension phenotypes such as white-coat hypertension (WCHT), diagnosed with the addition of nighttime blood pressure (BP) criteria, are related to coronary artery stenosis (CAS) and cardiac arrhythmia. In this cross-sectional observational study, 844 participants who did not use antihypertensive, lipid-lowering, and antiplatelet drugs were selected. The subjects were divided into normotensive (NT), WCHT, masked hypertension (MHT), and sustained hypertension (SHT) groups based on the results of clinic BP measurement and ambulatory BP monitoring. Coronary angiography and ambulatory electrocardiography were performed to determine the participants' CAS and cardiac arrhythmia status. Coronary angiography revealed 556 patients with CAS and 288 participants with normal coronary arteries. The chi-squared test showed that the incidence of CAS was higher in the MHT and SHT groups than in the NT group, while no significant change was found in the WCHT group (P = 0.003, P < 0.001, P = 0.119). The logarithm of the Gensini score was used to compare the degree of CAS between the groups. Multiple linear regression analysis showed that the degree of CAS was higher in the WCHT, MHT, and SHT groups than in the NT group (P < 0.05). The incidences of frequent atrial premature beats, atrial tachycardia, and ventricular cardiac arrhythmia were significantly higher in the WCHT and SHT groups than in the NT group, while only ventricular cardiac arrhythmia changes were observed in the MHT group. This study found that hypertension phenotypes such as WCHT were closely associated with CAS and cardiac arrhythmia.

Development of Predictive Equations for Nocturnal Hypertension and Nondipping Systolic Blood Pressure

Background Nocturnal hypertension, defined by a mean asleep systolic blood pressure (SBP)/diastolic blood pressure (BP) ≥120/70 mm Hg, and nondipping SBP, defined by an awake-to-asleep decline in SBP <10%, are each associated with increased risk for cardiovascular disease. Methods and Results We developed predictive equations to identify adults with a high probability of having nocturnal hypertension or nondipping SBP using data from the CARDIA (Coronary Artery Risk Development in Young Adults) study (n=787), JHS (Jackson Heart Study) (n=1063), IDH (Improving the Detection of Hypertension) study (n=395), and MHT (Masked Hypertension) study (n=772) who underwent 24-hour ambulatory BP monitoring. Participants were randomized to derivation (n=2511) or validation (n=506) data sets. The prevalence rates of nocturnal hypertension and nondipping SBP were 39.7% and 44.9% in the derivation data set, respectively, and 36.6% and 44.5% in the validation data set, respectively. The predictive equation for nocturnal hypertension included age, race/ethnicity, smoking status, neck circumference, height, high-density lipoprotein cholesterol, albumin/creatinine ratio, and clinic SBP and diastolic BP. The predictive equation for nondipping SBP included age, sex, race/ethnicity, waist circumference, height, alcohol use, high-density lipoprotein cholesterol, and albumin/creatinine ratio. Concordance statistics (95% CI) for nocturnal hypertension and nondipping SBP predictive equations in the validation data set were 0.84 (0.80-0.87) and 0.73 (0.69-0.78), respectively. Compared with reference models including antihypertensive medication use and clinic SBP and diastolic BP as predictors, the continuous net reclassification improvement (95% CI) values for the nocturnal hypertension and nondipping SBP predictive equations were 0.52 (0.35-0.69) and 0.51 (0.34-0.69), respectively. Conclusions These predictive equations can direct ambulatory BP monitoring toward adults with high probability of having nocturnal hypertension and nondipping SBP.

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.

Home Blood Pressure Monitoring in Cases of Clinical Uncertainty to Differentiate Appropriate Inaction From Therapeutic Inertia

PURPOSE

Conventional clinic blood pressure (BP) measurements are routinely used for hypertension management and physician performance measures. We aimed to check home BP measurements after elevated conventional clinic BP measurements for which physicians did not intensify treatment, to differentiate therapeutic inertia from appropriate inaction.

METHODS

We conducted a pre and post study of home BP monitoring for patients with uncontrolled hypertension as determined by conventional clinic BP measurements for which physicians did not intensify hypertension management. Physicians were notified of average home BP 2-4 weeks after the initial clinic visit. Outcome measures were the proportion of patients with controlled hypertension using average home BP measurements, changes in hypertension management by physicians, changes in physicians' hypertension metrics, and factors associated with home-clinic BP differences.

RESULTS

Of 90 recruited patients who had elevated conventional clinic BP recordings, 65.6% had average home BP measurements that were <140/90 mm Hg. Physicians changed treatment plans for 61% of patients with average home BP readings of ≥140/90 mm Hg, whereas decisions to not change treatment for the remaining patients were based on contextual factors. Substituting average home BP for conventional clinic BP for 4% of patients from 2 physicians' hypertension registries improved the physicians' hypertension control rates by 3% to 5%. Greater body mass index and increased number of BP medications were associated with home BP measurement ≥140/90 mm Hg. Clinic BP levels did not estimate normal home BP levels.

CONCLUSIONS

Documented home BP in cases of clinical uncertainty helped differentiate therapeutic inertia from appropriate inaction and improved physicians' hypertension metrics.

Masked Hypertension: Whom and How to Screen?

PURPOSE OF REVIEW

To review issues regarding the practical implementation of screening strategies for masked hypertension.

RECENT FINDINGS

Masked hypertension has been associated with an increased risk of cardiovascular disease events and all-cause mortality. Recent guidelines have encouraged practitioners to use out-of-clinic monitoring to detect masked hypertension in some situations. However, it is unclear from these guidelines who should be screened or how to best measure out-of-office blood pressure. In this review, challenges to screening strategies for masked hypertension, and factors that should be considered when deciding to screen using ambulatory or home blood pressure monitoring. Masked hypertension is an important clinical phenotype to detect. Future research is needed in order to develop optimal screening strategies, and to understand population level implications of using ambulatory or home blood pressure monitoring on blood pressure control.

Druggable targets in the Rho pathway and their promise for therapeutic control of blood pressure

The prevalence of high blood pressure (also known as hypertension) has steadily increased over the last few decades. Known as a silent killer, hypertension increases the risk for cardiovascular disease and can lead to stroke, heart attack, kidney failure and associated sequela. While numerous hypertensive therapies are currently available, it is estimated that only half of medicated patients exhibit blood pressure control. This signifies the need for a better understanding of the underlying cause of disease and for more effective therapies. While blood pressure homeostasis is very complex and involves the integrated control of multiple body systems, smooth muscle contractility and arterial resistance are important contributors. Strong evidence from pre-clinical animal models and genome-wide association studies indicate that smooth muscle contraction and BP homeostasis are governed by the small GTPase RhoA and its downstream target, Rho kinase. In this review, we summarize the signaling pathways and regulators that impart tight spatial-temporal control of RhoA activity in smooth muscle cells and discuss current therapeutic strategies to target these RhoA pathway components. We also discuss known allelic variations in the RhoA pathway and consider how these polymorphisms may affect genetic risk for hypertension and its clinical manifestations.

Diagnosing Masked Hypertension Using Ambulatory Blood Pressure Monitoring, Home Blood Pressure Monitoring, or Both?

Guidelines recommend measuring out-of-clinic blood pressure (BP) to identify masked hypertension (MHT) defined by out-of-clinic BP in the hypertensive range among individuals with clinic-measured BP not in the hypertensive range. The aim of this study was to determine the overlap between ambulatory BP monitoring (ABPM) and home BP monitoring (HBPM) for the detection of MHT. We analyzed data from 333 community-dwelling adults not taking antihypertensive medication with clinic BP <140/90 mm Hg in the IDH study (Improving the Detection of Hypertension). Any MHT was defined by the presence of daytime MHT (mean daytime BP ≥135/85 mm Hg), 24-hour MHT (mean 24-hour BP ≥130/80 mm Hg), or nighttime MHT (mean nighttime BP ≥120/70 mm Hg). Home MHT was defined as mean BP ≥135/85 mm Hg on HBPM. The prevalence of MHT was 25.8% for any MHT and 11.1% for home MHT. Among participants with MHT on either ABPM or HBPM, 29.5% had MHT on both ABPM and HBPM; 61.1% had MHT only on ABPM; and 9.4% of participants had MHT only on HBPM. After multivariable adjustment and compared with participants without MHT on ABPM and HBPM, those with MHT on both ABPM and HBPM and only on ABPM had a higher left ventricular mass index (mean difference [SE], 12.7 [2.9] g/m2, P<0.001; and 4.9 [2.1] g/m2, P=0.022, respectively), whereas participants with MHT only on HBPM did not have an increased left ventricular mass index (mean difference [SE], -1.9 [4.8] g/m2, P=0.693). These data suggest that conducting ABPM will detect many individuals with MHT who have an increased cardiovascular disease risk.

Number of Measurements Needed to Obtain a Reliable Estimate of Home Blood Pressure: Results From the Improving the Detection of Hypertension Study

Background Obtaining out-of-clinic blood pressure ( BP ) measurements to confirm a diagnosis of hypertension is recommended before initiating treatment. There are few empiric data available on the number of measurements required to reliably estimate BP on home BP monitoring ( HBPM ). Methods and Results We analyzed data from 316 community-dwelling adults not taking antihypertensive medication from the IDH (Improving the Detection of Hypertension) study who performed HBPM for 14 days. The reliability of home BP measurements was assessed using the intraclass correlation coefficient and as the percentage of participants with an absolute difference in home BP <10 mm Hg between weeks. The reliability of home hypertension status was assessed by the κ statistic. In the IDH study, 13.6% of participants had clinic hypertension and 18.0% had home hypertension. Mean home systolic and diastolic BP exhibited excellent reliability and sufficient agreement using the average of 2 morning and 2 evening BP readings for a minimum of 2 days of HBPM and a single morning and single evening or 2 morning BP readings for a minimum of 3 days. For diagnosing home hypertension, there was good agreement with a minimum of 3 days of HBPM using the average of 2 morning and 2 evening measurements or a single morning and single evening BP reading. A greater number of days was required for the other HBPM strategies. Conclusions Using the average of morning and evening readings, 3 days of HBPM are needed to reliably estimate mean home BP and diagnose out-of-clinic hypertension.

Association of ambulatory blood pressure variability with coronary artery calcium

Blood pressure (BP) variability is associated with progression to clinical atherosclerosis. The evidence is inconclusive if BP variability predicts cardiovascular outcomes in low-risk populations. The aim of this study was to analyze the association of 24-hour BP variability with coronary artery calcium (CAC) among a group of individuals without coronary artery disease. The Masked Hypertension Study targeted patients with borderline high BP (120-149 mm Hg systolic and/or 80-95 mm Hg diastolic). Ambulatory blood pressure monitoring (ABPM) was performed at two time-points, 8 days apart. CAC was measured at exit visit via cardiac CT and reported as Agatston Score. Weighted standard deviations and average real variability were calculated from ABPM. Of the 322 participants who underwent cardiac CT, 26% (84) had CAC present, 52% (168) were female, and 21% (64) were black. BP variability did not differ by CAC group. In this low cardiovascular risk group, CAC was not associated with 24-hour ambulatory BP variability.

An Update on Masked Hypertension

Masked hypertension refers to the phenomenon of having a non-elevated clinic blood pressure (BP) despite having an elevated out-of-clinic BP. Masked hypertension is a common phenotype with a cardiovascular risk profile similar to that of sustained hypertension, defined as elevated clinic and out-of-clinic BP. Current guidelines offer little guidance on the best practices for detecting and treating masked hypertension. This is in part due to insufficient evidence upon which to base recommendations as many questions remain regarding the optimal clinical management of masked hypertension. In this review, we will discuss the recent literature on masked hypertension related to disease prevalence, diagnosis, screening strategies, adverse outcomes, and treatment, and will highlight critical areas for future research.

Predicted Atherosclerotic Cardiovascular Disease Risk and Masked Hypertension Among Blacks in the Jackson Heart Study

BACKGROUND

Among individuals without hypertension based on clinic blood pressure (BP), it is unclear who should be screened for masked hypertension, defined as having hypertension based on out-of-clinic BP. We hypothesized that individuals with a higher 10-year predicted atherosclerotic cardiovascular disease (ASCVD) risk, calculated using the pooled cohort risk equations, have a higher prevalence of masked hypertension.

METHODS AND RESULTS

We analyzed data from the Jackson Heart Study-a population-based cohort of blacks-to determine the association of predicted ASCVD risk with masked hypertension. The sample included 644 participants, 40 to 79 years of age, with clinic systolic/diastolic BP <140/90 mm Hg, who completed ambulatory BP monitoring, were free of cardiovascular disease, and had data on factors needed to calculate ASCVD risk. Ten-year predicted ASCVD risk was calculated using the pooled cohort risk equations. Any masked hypertension was defined as masked daytime hypertension (mean daytime systolic/diastolic BP ≥135/85 mm Hg), masked nighttime hypertension (mean nighttime systolic/diastolic BP ≥120/70 mm Hg), or masked 24-hour hypertension (mean 24-hour systolic/diastolic BP ≥130/80 mm Hg). The prevalence of any masked hypertension was 54.0%. Compared with participants in the lowest (<5%) predicted ASCVD risk category, multivariable-adjusted prevalence ratios (95% confidence interval) for any masked hypertension were 1.36 (1.03-1.79), 1.62 (1.22-2.16), and 1.91 (1.47-2.48) for those with ASCVD risk of 5% to <7.5%, 7.5% to <10%, and ≥10%, respectively. The C statistic for discriminating between participants with versus without any masked hypertension was 0.681 (95% confidence interval, 0.640-0.723) for ASCVD risk and 0.703 (95% confidence interval, 0.663-0.744) for clinic systolic BP and diastolic BP.

CONCLUSIONS

Higher ASCVD risk was associated with an increased prevalence of masked hypertension. Although the discrimination of ASCVD risk for masked hypertension was not superior to clinic BP, risk prediction equations may be useful for identifying the subgroup of individuals with both masked hypertension and high predicted ASCVD risk.

Metabolic syndrome and masked hypertension among African Americans: The Jackson Heart Study

The metabolic syndrome is associated with higher ambulatory blood pressure. The authors studied the association of metabolic syndrome and masked hypertension (MHT) among African Americans with clinic-measured systolic/diastolic blood pressure (SBP/DBP) <140/90 mm Hg in the Jackson Heart Study. MHT was defined as daytime, nighttime, or 24-hour hypertension on ambulatory blood pressure monitoring. Among 359 participants not taking antihypertensive medication, the metabolic syndrome was associated with MHT (prevalence ratio, 1.38; 95% confidence interval, 1.10-1.74]). When metabolic syndrome components (clinic SBP/DBP 130-139/85-89 mm Hg, abdominal obesity, impaired glucose, low high-density lipoprotein cholesterol, high triglycerides) were analyzed separately, only clinic SBP/DBP 130-139/85-89 mm Hg was associated with MHT (prevalence ratio, 1.90; 95% confidence interval, 1.56-2.32]). The metabolic syndrome was not associated with MHT among participants not taking antihypertensive medication with SBP/DBP 130-139/85-89 and <130/85 mm Hg, separately, or among participants taking antihypertensive medication (n=393). Ambulatory blood pressure monitoring screening for MHT among African Americans should be considered based on clinic BP, not metabolic syndrome.

Masked Hypertension and Cardiovascular Disease Events in a Prospective Cohort of Blacks: The Jackson Heart Study

Masked hypertension, defined as nonelevated clinic blood pressure (BP) with elevated out-of-clinic BP, has been associated with increased cardiovascular disease (CVD) risk in Europeans and Asians. Few data are available on masked hypertension and CVD and mortality risk among blacks. We analyzed data from the Jackson Heart Study, a prospective cohort study of blacks. Analyses included participants with clinic-measured systolic/diastolic BP <140/90 mm Hg who completed ambulatory BP monitoring after the baseline examination in 2000 to 2004 (n=738). Masked daytime (10:00 am-8:00 pm) hypertension was defined as mean ambulatory systolic/diastolic BP ≥135/85 mm Hg. Masked nighttime (midnight to 6:00 am) hypertension was defined as mean ambulatory systolic/diastolic BP ≥120/70 mm Hg. Masked 24-hour hypertension was defined as mean systolic/diastolic BP ≥130/80 mm Hg. CVD events (nonfatal/fatal stroke, nonfatal myocardial infarction, or fatal coronary heart disease) and deaths identified through December 2010 were adjudicated. Any masked hypertension (masked daytime, nighttime, or 24-hour hypertension) was present in 52.2% of participants; 28.2%, 48.2% and 31.7% had masked daytime, nighttime, and 24-hour hypertension, respectively. There were 51 CVD events and 44 deaths during a median follow-up of 8.2 and 8.5 years, respectively. CVD rates per 1000 person-years (95% confidence interval) in participants with and without any masked hypertension were 13.5 (9.9-18.4) and 3.9 (2.2-7.1), respectively. The multivariable adjusted hazard ratio (95% confidence interval) for CVD was 2.49 (1.26-4.93) for any masked hypertension and 2.86 (1.59-5.13), 2.35 (1.23-4.50), and 2.52 (1.39-4.58) for masked daytime, nighttime, and 24-hour hypertension, respectively. Masked hypertension was not associated with all-cause mortality. Masked hypertension is common and associated with increased risk for CVD events in blacks.