Attended Versus Unattended Automated Office Blood Pressure: A Systematic Review and Meta-analysis

Impact of Successive Office Blood Pressure Measurements During a Single Visit on Cardiovascular Risk Prediction: Analysis of CARTaGENE

BACKGROUND

Multiple office blood pressure (BP) readings correlate more closely with ambulatory BP than single readings. Whether they are associated with long-term outcomes and improve cardiovascular risk prediction is unknown. Our objective was to assess the long-term impact of multiple office BP readings.

METHODS

We used data from CARTaGENE, a population-based survey comprising individuals aged 40 to 70 years. Three BP readings (BP1, BP2, and BP3) at 2-minute intervals were obtained using a semiautomated device. They were averaged to generate BP1-2, BP2-3, and BP1-2-3 for systolic BP (SBP) and diastolic BP. Cardiovascular events (major adverse cardiovascular event [MACE]: cardiovascular death, stroke, and myocardial infarction) during a 10-year follow-up were recorded. Associations with MACE were obtained using adjusted Cox models. Predictive performance was assessed with 10-year atherosclerotic cardiovascular disease scores and their associated C statistics.

RESULTS

In the 17 966 eligible individuals, 2378 experienced a MACE during follow-up. Crude SBP values ranged from 122.5 to 126.5 mm Hg. SBP3 had the strongest association with MACE incidence (hazard ratio, 1.10 [1.05-1.15] per SD) and SBP1 the weakest (hazard ratio, 1.06 [1.01-1.10]). All models including SBP1 (SBP1, SBP1-2, and SBP1-2-3) were underperformed. At a given SBP value, the excess MACE risk conferred by SBP3 was 2× greater than SBP1. In atherosclerotic cardiovascular disease scores, SBP3 yielded the highest C statistic, significantly higher than most other SBP measures. In contrast to SBP, all diastolic BP readings yielded similar results.

CONCLUSIONS

Cardiovascular risk prediction is improved by successive office SBP values, especially when the first reading is discarded. These findings reinforce the necessity of using multiple office BP readings.

Comparison of nurse attended and unattended automated office blood pressure with conventional measurement techniques in clinical practice

Accuracy in blood pressure measurement is critical for proper hypertension diagnosis and treatment in clinical practice. Automated office blood pressure (AOBP) can simplify the measurement process, reducing human error and minimizing the white-coat effect in the unattended mode. The aim of this study was to compare AOBP, both unattended and nurse attended, with conventional office and out-of-office blood pressure measurement techniques. Four different methods of blood pressure measurement were performed in a cohort of hypertensive patients: conventional office blood pressure (OBP), unattended automated office blood pressure (uAOBP), nurse attended automated office blood pressure (nAOBP), and home blood pressure monitoring (HBPM). uAOBP and nAOBP were conducted with the same rigorous standardized procedure. We enrolled 118 consecutive patients. nAOBP values were slightly higher than uAOBP ones (respectively 132.8/73.3 ± 19.4/12.9 and 129.2/71.1 ± 19.0/12.3 mmHg), even if the difference was influenced by order of execution of AOBP measurement. nAOBP was significantly lower than HBPM and OBP (mean values 135.2/80.9 ± 16.6/8.1 and 140.9/84.6 ± 18.7/10.8 mmHg, respectively). AOBP, either attended or unattended, provides lower values than conventional OBP. uAOBP and nAOBP values showed small differences, even if they are not completely interchangeable. This evidence reflects a lower white-coat effect, even in nurse attended technique, but is also due to a lower measurement error through the application of a rigorous standardized protocol.

Automated Office Blood Pressure and the Impact of Attendance and Rest on Diagnostic Accuracy

BACKGROUND

Automated office blood pressure (AOBP) using 3-5 measurements taken with an oscillometric device with or without an attendant in the room may decrease "white coat" effect. We evaluated the impact of the presence or absence of the attendant and rest on BP and diagnosis of hypertension.

METHODS

We randomly assigned 133 adults aged 18-85 with high BP at baseline (≥140/90 mm Hg), no hypertensive diagnosis and no antihypertensive medications to either attended AOBP first, unattended second, or unattended AOBP first, attended second. Outcomes included within-person BP difference for attended vs. unattended measurements; 5 vs. 15 minutes of rest; and the diagnostic performance of AOBP compared with daytime automated blood pressure measurement (ABPM).

RESULTS

We found no significant differences between attended and unattended AOBP (mean difference attended - unattended [95% confidence interval, CI], systolic 0.14 mm Hg [-0.78, 1.06]; diastolic 0.16 mm Hg [-0.45, 0.78]) or by rest time (mean difference 15 - 5 minutes [95% CI], systolic -0.45 mm Hg [-1.36, 0.47]; diastolic 0.61 mm Hg [-1.23, 0.003]). AOBP was lower than mean daytime ABPM, regardless of attendance or rest (after 5 minutes rest systolic -3.6 and diastolic -2.55 mm Hg, P = 0.001 for both comparisons). Using daytime ABPM of ≥135/85 mm Hg as the diagnostic threshold, AOBP sensitivity and specificity after 5 minutes of rest were 71.0% and 54.1%, respectively.

CONCLUSIONS

The presence or absence of a clinic attendant during AOBP measurement and the amount of rest time before AOBP measurements had no effects on BP. AOBP measurements have low sensitivity and specificity for making a new diagnosis of hypertension.

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

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

Blood pressure measurement: Should technique define targets?

Accurate assessment of blood pressure (BP) is the cornerstone of hypertension management. The objectives of this study were to quantify the effect of medical personnel presence during BP measurement by automated oscillometric BP (AOBP) and to compare resting office BP by AOBP to daytime average BP by 24‐h ambulatory BP monitoring (ABPM). This study is a prospective randomized cross‐over trial, conducted in a referral population. Patients underwent measurements of casual and resting office BP by AOBP. Resting BP was measured as either unattended (patient alone in the room during resting and measurements) or as partially attended (nurse present in the room during measurements) immediately prior to and after 24‐h ABPM. The primary outcome was the effect of unattended 5‐min rest preceding AOBP assessment as the difference between casual and resting BP measured by the Omron HEM 907XL. Ninety patients consented and 78 completed the study. The mean difference between the casual and Omron unattended systolic BP was 7.0 mm Hg (95% confidence interval [CI] 4.5, 9.5). There was no significant difference between partially attended and unattended resting office systolic BP. Resting office BP (attended and partially attended) underestimated daytime systolic BP load from 24‐h ABPM. The presence or absence of medical personnel does not impact casual office BP which is higher than resting office AOBP. The requirement for unattended rest may be dropped if logistically challenging. Casual and resting office BP readings by AOBP do not capture the complexity of information provided by the 24‐h ABPM.

Comparison Between Automated Office Blood Pressure Measurements and Manual Office Blood Pressure Measurements-Implications in Individual Patients: a Systematic Review and Meta-analysis

PURPOSE OF REVIEW

Automated office blood pressure (AOBP) measurements may provide more accurate estimation of blood pressure (BP) than manual office blood pressure (MOBP) measurements. This systematic review investigated the diagnostic performance of AOBP and MOBP using ambulatory blood pressure measurement (ABPM) as reference. Several databases including MEDLINE, Embase, Scopus, and China Academic Journals were searched. Data were extracted, double-checked by two investigators, and were analysed using a random effects model.

RECENT FINDINGS

A total of 26 observational studies were included. The mean systolic/diastolic BP obtained by AOBP was not significantly different from that obtained by ABPM. The sensitivity and specificity of AOBP to detect elevated BP were approximately 70%. Fewer participants had white-coat hypertension on AOBP measurement than on MOBP measurement (7% versus 14%); however, about 13% had masked hypertension on AOBP measurement. The width of the limit of agreement comparing (i) AOBP and ABPM and (ii) MOBP and ABPM was comparable. AOBP may reduce the rate of the observed white-coat effect but undermine masked hypertension. The current recommendation, however, is limited by the absence of high-quality studies and the high heterogeneity of our results. More high-quality studies using different AOBP machines and in different population are therefore needed.

Recent advances in managing primary hypertension

Hypertension remains a leading risk factor for cardiovascular mortality and morbidity globally despite the availability of effective and well-tolerated antihypertensive medications. Accumulating evidence suggests a more aggressive blood pressure regulation aimed at lower targets, particularly for selected patient groups. Our concepts of the optimal method for blood pressure measurement have radically changed, maintaining appropriate standard office measurements for initial assessment but relying on out-of-office measurement to better guide our decisions. Thorough risk stratification provides guidance in decision making; however, an individualized approach is highly recommended to prevent overtreatment. Undertreatment, on the other hand, remains a major concern and is mainly attributed to poor adherence and resistant or difficult-to-control forms of the disease. This review aims to present modern perspectives, novel treatment options, including innovative technological applications and developing interventional and pharmaceutical therapies, and the major concerns emerging from several years of research and epidemiological observations related to hypertension management.

Resistant hypertension-defining the scope of the problem

The updated scientific statement by the American Heart Association has defined resistant hypertension (HTN;RH) as uncontrolled blood pressure (BP) ≥ 130/80 mmHg, despite concurrent use of 3 anti-HTN drug classes comprising a calcium channel blocker, a blocker of renin-angiotensin system, and a thiazide diuretic, preferably chlorthalidone. Using the updated BP criteria, the prevalence of RH in the United States is found to be modestly increased by approximately 3-4% among treated population. Meta-analysis of observational studies have demonstrated that pseudo-RH from white coat HTN or medication nonadherence is as much common as the truly RH. Thus, screening for pseudo-resistance in the evaluation of all apparent RH is of utmost importance as diagnosis of white-coat HTN requires no treatment, while medication nonadherence would benefit from identifying and targeting barriers to adherence.