Ambulatory versus home blood pressure monitoring: frequency and determinants of blood pressure difference and diagnostic disagreement

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.

The role of wearable home blood pressure monitoring in detecting out-of-office control status

Ambulatory blood pressure (ABP) and home blood pressure (HBP) monitoring is currently recommended for management of hypertension. Nonetheless, traditional HBP protocols could overlook diurnal fluctuations, which could also be linked with adverse cardiovascular outcomes. In this observational study, we studied among a group of treated hypertensive patients (N = 62, age: 52.4 ± 10.4 years) by using out-of-office ABP and wearable HBP. They received one session of 24-h ABP measurement with an oscillometric upper-arm monitor, and totally three sessions of 7-day/6-time-daily wearable HBP measurement separated in each month with HeartGuide. Controlled hypertension is defined as an average BP <130/80 mmHg for both daytime ABP and HBP. There was substantial reliability (intraclass correlation coefficient, ICC 0.883-0.911) and good reproducibility (Cohen's kappa = 0.600) for wearable HBP measurement, especially before breakfast and after dinner. Among all patients, 27.4% had both uncontrolled HBP and ABP, 30.6% had uncontrolled HBP only, while 6.5% had uncontrolled ABP only. Female gender and increased numbers of anti-hypertensive agents are correlated with controlled hypertension. Patients with uncontrolled hypertension had a significantly higher maximal daytime blood pressure, which was previously signified as an imperial marker for cardiovascular risk. In conclusion, wearable HBP monitoring in accordance with a dedicated daily-living schedule results in good reliability and reproducibility. Patients with an uncontrolled wearable HBP should benefit from repeated HBP or ABP measurement for risk stratification.

Comparison of office, home and ambulatory blood pressure measurements in hypertensive and suspected hypertensive SWICOS participants

PURPOSE

Hypertension should be confirmed with the use of home BP measurement (HBPM) or 24h ambulatory BP measurement (ABPM). The aim of our study was to compare measurements obtained by OBPM, HBPM and ABPM in individuals with elevated OBPM participating in the population-based Swiss Longitudinal Cohort Study (SWICOS).

MATERIAL AND METHODS

Participants with OBPM ≥140/90 mmHg assessed their BP using HBPM and ABPM. The cut-off for hypertension was ≥135/85 mmHg for HBPM, ≥130/80 mmHg for ABPM. White-coat hypertension (WCH) was defined as normal HPBM and ABPM in participants not taking antihypertensive drugs. Uncontrolled hypertension was defined as hypertension in HBPM or ABPM despite antihypertensive treatment.

RESULTS

Of 72 hypertensive subjects with office BP ≥140/90 mmHg and valid measurements of HBPM and ABPM, 39 were males (aged 62.8 ± 11.8y), 33 were females (aged 57.4 ± 14.2y). Hypertension was confirmed with HBPM and ABPM in 17 participants (24%), with ABPM only in 24 further participants (33%), and with HBPM only in 2 further participants (3%). Participants who had hypertension according to ABPM but not HBPM were younger (59 ± 11 y versus 67 ± 16 y; p < 0.001) and more frequently still working (83% versus 23%; p < 0.001). The prevalence of WCH was 28%. Among the 32 subjects taking antihypertensive drugs, uncontrolled hypertension was found in 49%.

CONCLUSION

This population-based study found a high prevalence of WCH and potential uncontrolled hypertension among individuals with elevated OBPM. This study, therefore, supports the ESH recommendations of complementing OBPM by ABPM or HBPM. The use of HBPM instead of ABPM for the confirmation of hypertension in individuals with elevated OBPM might lead to underdiagnosis and uncontrolled hypertension, in particular in the younger working population. In these individuals, this study suggests using ABPM instead of HBPM.

Inconsistent Control Status of Office, Home, and Ambulatory Blood Pressure All Taken Using the Same Device: The HI-JAMP Study Baseline Data

BACKGROUND

Inconsistencies between the office and out-of-office blood pressure (BP) values (described as white-coat hypertension or masked hypertension) may be attributable in part to differences in the BP monitoring devices used.

METHODS

We studied consistency in the classification of BP control (well-controlled BP vs. uncontrolled BP) among office, home, and ambulatory BPs by using a validated "all-in-one" BP monitoring device. In the nationwide, general practitioner-based multicenter HI-JAMP study, 2,322 hypertensive patients treated with antihypertensive drugs underwent office BP measurements and 24-hour ambulatory BP monitoring (ABPM), consecutively followed by 5-day home BP monitoring (HBPM), for a total of seven BP measurement days.

RESULTS

Using the thresholds of the JSH2019 and ESC2018 guidelines, the patients with consistent classification of well-controlled status in the office (<140 mmHg) and home systolic BP (SBP) (<135 mmHg) (n = 970) also tended to have well-controlled 24-hour SBP (<130 mmHg) (n = 808, 83.3%). The patients with the consistent classification of uncontrolled status in office and home SBP (n = 579) also tended to have uncontrolled 24-hour SBP (n = 444, 80.9%). Among the patients with inconsistent classifications of office and home BP control (n = 803), 46.1% had inconsistent ABPM-vs.-HBPM out-of-office BP control status. When the 2017 ACC/AHA thresholds were applied as an alternative, the results were essentially the same.

CONCLUSIONS

The combined assessment of the office and home BP is useful in clinical practice. Especially for patients whose office BP classification and home BP classification conflict, the complementary clinical use of both HBPM and ABPM might be recommended.

Diagnostic agreement of masked uncontrolled hypertension detected by ambulatory blood pressure and home blood pressure measured by an all-in-one BP monitoring device: The HI-JAMP study

Masked hypertension is defined by office blood pressure (BP) in the controlled-BP range while out-of-office BP measured by ambulatory BP monitoring (ABPM) and home BP monitoring (HBPM) is in the uncontrolled range. However, diagnosis of masked hypertension may differ if assessed by different out-of-office BP indices. This study aims to investigate the diagnostic agreement of masked uncontrolled hypertension (MUHT) detected by ABPM indices (ABPM-MUHT) and HBPM indices (HBPM-MUHT) using the same all-in-one device (TM2441; A&D Company). The present study enrolled a total of 2322 treated hypertensive patients (males 53.2%, average age 69.2 ± 11.5 years) from the Home-Activity ICT-based Japan Ambulatory Blood Pressure Monitoring Prospective (HI-JAMP) Study, who consecutively underwent office BP monitoring, 24-h ABPM (at 30-min intervals), and 5-day HBPM (twice each morning and evening) using the same device. When out-of-office BP control status was assessed only by 24-h average SBP or by the average of morning and evening SBP, the diagnostic agreement of MUHT detected by ABPM and HBPM was 29.7% among the 445 patients with any type of MUHT. When out-of-office BP indices in each time-window were simultaneously assessed, the diagnostic agreement increased to 40-45.7%. Our results indicated the importance of assessing BPs at various times of day, especially morning hours, for perfect hypertension management. Diagnosis of masked hypertension only by an averaged BP index, without considering specific time-windows, might underestimate cardiovascular risk.

Controversies in Hypertension I: The Optimal Assessment of Blood Pressure Load and Implications for Treatment

The most important factor in treating hypertension is assessing an individual patient's true blood pressure load, the cornerstone being research-grade office determination. Office blood pressure should be supplemented with out-of-office measurement, including home and ambulatory monitoring (if available), which we consider complementary and not interchangeable. Controversy remains for initiation of treatment of white coat hypertension, where cardiovascular risk lies between normotension and sustained hypertension; antihypertensive therapy should be considered unless low cardiovascular risk, wherein pressures should be followed for progression to sustained hypertension. Available data do not support intensification of therapy for the white coat effect due to the similar cardiovascular risk to controlled hypertension. Given the higher cardiovascular risk of the masked effect, initiation of therapy for masked hypertension and intensification for masked uncontrolled hypertension are indicated, acknowledging the dearth of supporting data. Optimally, randomized controlled trials are needed to determine the benefit of treating the 4 incongruous phenotypes between office and out-of-office measurements, that is, those with white coat or masked effects. We make no recommendations regarding chronotherapy pending results of ongoing trials.

Home blood pressure self-measurement: “Current situation and new perspectives”

The method typically used to diagnose and monitor hypertensive patients has been to measure blood pressure in the physician's surgery; however, it is a well-known fact that this approach poses certain drawbacks, such as observer bias, failure to detect an alert reaction in the clinic, etc., difficulties that affect its accuracy as a diagnostic method. In recent years, the varying international scientific societies have persistently recommended the use of blood pressure measurements outside the clinic (at home or in the outpatient setting), using validated automatic devices. Data from some studies suggest that if we rely solely on in-office measurements, approximately 15-20% of the time we may be wrong when making decisions, both in terms of diagnosis and patient follow-up. Home blood pressure measurements are a simple and very affordable method that has a similar reproducibility and prognostic value as ambulatory blood pressure monitoring, the availability of which is currently very limited. Moreover, ambulatory self-measurements have the significant benefit of being able to improve control of hypertensive individuals. Healthcare professionals and patients should be aware of the methodology of home blood pressure measurement, its usefulness and limitations.

Consistency among Office, Home, and Ambulatory Blood Pressure Values in Women with Chronic Hypertension and History of Eclampsia or Preeclampsia

Adequate control of blood pressure (BP) is essential to prevent complications in pregnant women with a history of eclampsia or pre-eclampsia. However, the importance of office (OBPM), home (HBPM), and ambulatory (ABPM) BP measurements for proper control and prognosis in high-risk pregnancy is unknown. The present study aimed to compare BP values obtained during these three different BP measurements in women with a history of eclampsia or pre-eclampsia. This study included 79 pregnant women with chronic hypertension and a documented history of eclampsia or pre-eclampsia in previous pregnancy/pregnancies. Every fifth week of the study, all participants underwent ABPM, HBPM and OBPM. BP values from the 10th, 25th, and 37th weeks of pregnancy were evaluated. Therapy was intended to meet the ABPM treatment goal of <130/80 mmHg. Day, night, and 24 h ABPM systolic BP values were lower than HBPM and OBPM values at each study visit. Night and 24 h ABPM diastolic BP values were lower than HBPM and OBPM values, while day 24 h ABPM values were slightly higher than HBPM and OBPM values. ABPM provides different BP values than OBPM and HBPM. Target BP for ABPM in high-risk pregnancy hypertension should be estimated based on the predictive value of adverse pregnancy outcomes.

Home blood pressure monitoring schedule: optimal and minimum based on 2122 individual participants' data

OBJECTIVES

Home blood pressure (HBP) monitoring has become a primary method for hypertension diagnosis and management. This analysis aimed to investigate the optimal and minimum schedule for HBP monitoring.

METHODS

A retrospective analysis of cross-sectional data was performed, which involved HBP and 24-h ambulatory blood pressure (ABP) monitoring in adults performed within the context of clinical studies in Finland, Greece and UK. Participants with six to seven HBP monitoring days and at least 12 HBP readings were included. The stability of HBP was assessed by evaluating the average value of an increasing number of readings and its variability (SD). Its association with awake ABP was also assessed.

RESULTS

Data from 2122 participants were analysed (mean age 53.9 ± 11.3 years, males 53%, treated 34%). A progressive HBP decline was observed in succeeding days, reaching a plateau after day 3. Day 1 HBP was higher than in the next days by about 2.8/1.4 mmHg (systolic/diastolic, P < 0.001). In a 3-day HBP monitoring schedule, the exclusion of day 1 reduced average HBP and SD, with a clinically important HBP decline in 115 participants (5%) and different hypertension diagnosis in 120 participants (6%). For schedules including more than three HBP monitoring days, the exclusion of day 1 had negligible impact. The 3-day average HBP was strongly correlated with awake ABP, with a little improvement thereafter.

CONCLUSION

These data support the recommendation for 7 days of HBP monitoring with a minimum of 3 days. Readings of the first day should be discarded, particularly when the minimum 3-day monitoring schedule is obtained (average readings of second and third day).

The assessment of blood pressure in pregnant women: pitfalls and novel approaches

Accurate assessment of blood pressure is fundamental to the provision of safe obstetrical care. It is simple, cost effective, and life-saving. Treatments for preeclampsia, including antihypertensive drugs, magnesium sulfate, and delivery, are available in many settings. However, the instigation of appropriate treatment relies on prompt and accurate recognition of hypertension. There are a number of different techniques for blood pressure assessment, including the auscultatory method, automated oscillometric devices, home blood pressure monitoring, ambulatory monitoring, and invasive monitoring. The auscultatory method with a mercury sphygmomanometer and the use of Korotkoff sounds was previously recommended as the gold standard technique. Mercury sphygmomanometers have been withdrawn owing to safety concerns and replaced with aneroid devices, but these are particularly prone to calibration errors and regular calibration is imperative to ensure accuracy. Automated oscillometric devices are straightforward to use, but the physiological changes in healthy pregnancy and pathologic changes in preeclampsia may affect the accuracy of a device and monitors must be validated. Validation protocols classify pregnant women as a "special population," and protocols must include 15 women in each category of normotensive pregnancy, hypertensive pregnancy, and preeclampsia. In addition to a scarcity of devices validated for pregnancy and preeclampsia, other pitfalls that cause inaccuracy include the lack of training and poor technique. Blood pressure assessment can be affected by maternal position, inappropriate cuff size, conversation, caffeine, smoking, and irregular heart rate. For home blood pressure monitoring, appropriate instruction should be given on how to use the device. The classification of hypertension and hypertensive disorders of pregnancy has recently been revised. These are classified as preeclampsia, transient gestational hypertension, gestational hypertension, white-coat hypertension, masked hypertension, chronic hypertension, and chronic hypertension with superimposed preeclampsia. Blood pressure varies across gestation and by ethnicity, but gestation-specific thresholds have not been adopted. Hypertension is defined as a sustained systolic blood pressure of ≥140 mm Hg or a sustained diastolic blood pressure of ≥90 mm Hg. In some guidelines, the threshold of diagnosis depends on the setting in which blood pressure measurement is taken, with a threshold of 140/90 mm Hg in a healthcare setting, 135/85 mm Hg at home, or a 24-hour average blood pressure on ambulatory monitoring of >126/76 mm Hg. Some differences exist among organizations with respect to the criteria for the diagnosis of preeclampsia and the correct threshold for intervention and target blood pressure once treatment has been instigated. Home blood pressure monitoring is currently a focus for research. Novel technologies, including early warning devices (such as the CRADLE Vital Signs Alert device) and telemedicine, may provide strategies that prompt earlier recognition of abnormal blood pressure and therefore improve management. The purpose of this review is to provide an update on methods to assess blood pressure in pregnancy and appropriate technique to optimize accuracy. The importance of accurate blood pressure assessment is emphasized with a discussion of preeclampsia prediction and treatment of severe hypertension. Classification of hypertensive disorders and thresholds for treatment will be discussed, including novel developments in the field.

Algorithm for diagnosing hypertension using out-of-office blood pressure measurements

The authors developed and validated a diagnostic algorithm using the optimal upper and lower cut‐off values of office and home BP at which ambulatory BP measurements need to be applied. Patients presenting with high BP (≥140/90 mm Hg) at the outpatient clinic were referred to measure office, home, and ambulatory BP. Office and home BP were divided into hypertension, intermediate (requiring diagnosis using ambulatory BP), and normotension zones. The upper and lower BP cut‐off levels of intermediate zone were determined corresponding to a level of 95% specificity and 95% sensitivity for detecting daytime ambulatory hypertension by using the receiver operator characteristic curve. A diagnostic algorithm using three methods, OBP‐ABP: office BP measurement and subsequent ambulatory BP measurements if office BP is intermediate zone; OBP‐HBP‐ABP: office BP, subsequent home BP measurement if office BP is within intermediate zone and subsequent ambulatory BP measurement if home BP is within intermediate zone; and HBP‐ABP: home BP measurement and subsequent ambulatory BP measurements if home BP is within intermediate zone, were developed and validated. In the development population (n = 256), the developed algorithm yielded better diagnostic accuracies than 75.8% (95%CI 70.1–80.9) for office BP alone and 76.2% (95%CI 70.5–81.3) for home BP alone as follows: 96.5% (95%CI: 93.4–98.4) for OBP‐ABP, 93.4% (95%CI: 89.6–96.1) for OBP‐HBP‐ABP, and 94.9% (95%CI: 91.5–97.3%) for HBP‐ABP.  In the validation population (n = 399), the developed algorithm showed similarly improved diagnostic accuracy. The developed algorithm applying ambulatory BP measurement to the intermediate zone of office and home BP improves the diagnostic accuracy for hypertension.

Hypertension Canada's 2020 Comprehensive Guidelines for the Prevention, Diagnosis, Risk Assessment, and Treatment of Hypertension in Adults and Children

Hypertension Canada's 2020 guidelines for the prevention, diagnosis, risk assessment, and treatment of hypertension in adults and children provide comprehensive, evidence-based guidance for health care professionals and patients. Hypertension Canada develops the guidelines using rigourous methodology, carefully mitigating the risk of bias in our process. All draft recommendations undergo critical review by expert methodologists without conflict to ensure quality. Our guideline panel is diverse, including multiple health professional groups (nurses, pharmacy, academics, and physicians), and worked in concert with experts in primary care and implementation to ensure optimal usability. The 2020 guidelines include new guidance on the management of resistant hypertension and the management of hypertension in women planning pregnancy.

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.

Characteristics of Individuals with Disagreement between Home and Ambulatory Blood Pressure Measurements for the Diagnosis of Hypertension

Home and ambulatory blood pressure (BP) measurements are recommended for the diagnosis of hypertension. However, the clinical characteristics of individuals showing a diagnostic disagreement between their home and ambulatory BP measurements are unclear. Of the 470 individuals who were not on antihypertensive drug treatment with a BP ≥140/90 mmHg at an outpatient clinic, 399 who had valid office, home, and ambulatory BP results were included. Hypertension was diagnosed based on an average home BP ≥135/85 mmHg and/or an average daytime ambulatory BP ≥135/85 mmHg. The participants were divided into three groups: Agree-NT (home and ambulatory BP normotension), Disagree (home BP normotension and ambulatory BP hypertension, or home BP normotension and ambulatory BP hypertension), and Agree-HT (home and ambulatory BP hypertension). Eighty-four individuals (21.1%) were classified as the Disagree group. The mean serum creatinine, triglycerides, and electrocardiogram voltage in the Disagree group were intermediate between those observed in the Agree-NT and the Agree-HT group. In the Disagree group, the mean levels of office and home diastolic BP, all of the components of ambulatory BP, the aortic systolic BP, and the BP variabilities were found to be intermediate between those of the Agree-NT and the Agree-HT groups. These results indicate that individuals showing a diagnostic disagreement between their home and ambulatory BP may have cardiovascular risks that are intermediate between those with sustained home and ambulatory normotension and hypertension.

Are Automated Office Blood Pressure Readings More Variable Than Home Readings?

A recent report from the American Heart Association stated that automated office blood pressure (AOBP) is preferred for evaluating office blood pressure (BP) because it is more accurate and devoid of white coat effect, which is mostly caused by higher systolic BP readings. However, AOBP has been criticized for being too variable to be used for identifying patients with possible hypertension. We, therefore, compared AOBP with home BP monitoring (HBPM) with respect to variability as determined by their relationship with the gold standard for determining BP status, awake ambulatory BP (ABP). The main focus was on systolic BP. Data on AOBP, HBPM, and awake ABP were collected on 300 patients referred from the community for 24-hour ambulatory BP monitoring. The SD of the difference between mean systolic awake ABP (136.4±11.5) and AOBP (131.2±15.7) was 13.6 mm Hg compared with 13.1 for the SD of the difference ( P =0.52) between the systolic awake ABP and the HBPM (136.7±16.1). Coefficients of correlation were slightly lower for systolic awake ABP versus AOBP ( r =0.54) compared with HBPM ( r =0.60). Coefficients of variation for AOBP (12.0%) and HBPM (11.8%) and variances between AOBP and HBPM were similar. Of the 139 patients with hypertension as defined by a manual office systolic BP ≥140 mm Hg, variability in BP readings as determined by the SDs of the mean difference versus awake ABP were similar ( P =0.56) for AOBP (14.6) and HBPM (13.9). Overall, both systolic AOBP and HBPM exhibited a similar degree of variability as assessed by the various methods.