Cost-effectiveness of noninvasive central blood pressure monitoring in the diagnosis of hypertension

Guiding Hypertension Management Using Different Blood Pressure Monitoring Strategies (GYMNs study): comparison of three different blood pressure measurement methods: study protocol for a randomized controlled trial

Background

Home blood pressure (BP) and unattended automated BP (uAOBP) monitoring have been recommended by guidelines for the care of hypertensive subjects. However, BP measurements in the peripheral arteries cannot serve as direct substitutes for their central counterparts. Moreover, the comparative effectiveness and safety of BP-guided strategies using these BP measuring devices have never been evaluated.

Methods/design

Patients with uncontrolled or newly diagnosed hypertension aged 20–90 years will be recruited via outpatient clinics and allocated into three arms by stratified randomization (baseline systolic BP 130–155 mmHg and 155–180 mmHg): home BP, uAOBP, and central BP-guided treatment. At each scheduled visit to the clinic, a patient’s BP will be measured by each of the three methods of measuring BP. The blood pressure from three different methods will be confirmed available at each visit. Patients and physicians will be blinded to the allocated interventions because they will use measured BP values in the clinic through a standardized report format. A common BP target for systolic blood pressure (SBP) of 130 mmHg is adopted for these BP-guided strategies. The primary outcome is the change of 24-h mean ambulatory SBP at 3 months. A key secondary outcome is to determine the percentage achieving their target BPs at 3 months and the decrease of left ventricular mass at 12 months.

Discussion

To our knowledge, this is the first prospective double-blind randomized controlled trial to assess the optimal guiding strategy for hypertension. It will help to define which BP monitoring method is the most effective for guiding the clinical management of hypertension. It will provide good evidence to support future guideline recommendations for BP monitoring devices.

Trial registration

ClinicalTrials.gov, NCT03578848. Registered on 4 June 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3366-8) contains supplementary material, which is available to authorized users.

2019 Consensus of the Taiwan Hypertension Society and Taiwan Society of Cardiology on the Clinical Application of Central Blood Pressure in the Management of Hypertension

The Taiwan Society of Cardiology (TSOC) and the Taiwan Hypertension Society (THS) have appointed a joint consensus group for the 2019 Consensus of the TSOC and THS on the Clinical Application of Central blood pressure (BP) in the Management of Hypertension with the aim of formulating a management consensus on the clinical application of central BP in the management of hypertension. This consensus document focuses on the clinical application of central BP in the care of patients with hypertension. The major determinants of central BP are increased arterial stiffness and wave reflection, which are also the dominant hemodynamic manifestations of vascular aging. Central BP can be measured noninvasively using various techniques, including with convenient cuff-based oscillometric central BP monitors. Noninvasive central BP is better than conventional brachial BP to assess target organ damage and long-term cardiovascular outcomes. Based on the analysis of long-term events, a central BP threshold of 130/90 mmHg for defining hypertension has been proposed. Recent studies have suggested that a central BP strategy to confirm a diagnosis of hypertension may be more cost-effective than conventional strategies, and that guiding hypertension management with central BP may result in the use of fewer medications to achieve BP control. Although noninvasive measurements of brachial BP are inaccurate and central BP has been shown to carry superior prognostic value beyond brachial BP, the use of central BP should be justified in studies comparing central BP-guided therapeutic strategies with conventional care for cardiovascular events.

Peripheral maternal haemodynamics across pregnancy in hypertensive disorders of pregnancy

OBJECTIVES

Evaluating maternal haemodynamics across pregnancy in uncomplicated pregnancies and those complicated by hypertensive disorders of pregnancy (HDP).

STUDY DESIGN

Prospective cohort study from 2015 to 2018 of healthy, nulliparous, singleton-bearing women. Maternal haemodynamics assessed by Uscom BP+ at 9-16 and 32-36 weeks' gestation in pregnancies complicated by HDP [preeclampsia with severe (sPE n = 12) and without severe clinical features (nsPE n = 49), gestational hypertension (GH n = 25), transient gestational hypertension (TGH n = 33)] were compared to uncomplicated pregnancies (n = 286) using mixed-effects linear modelling.

MAIN OUTCOME MEASURES

Maternal haemodynamic adaptation in uncomplicated pregnancies and those complicated by HDP.

RESULTS

Between the two measurements, haemodynamic adaptation in women with sPE and nsPE was significantly different compared to those with uncomplicated pregnancies. An additional increase was observed for peripheral systolic blood pressure [SBP; 14.3 mmHg, 8.6-20.1 (sPE)], peripheral diastolic blood pressure [DBP; 7.7 mmHg, 3.3-12.1 (sPE); 2.6 mmHg, 3.3-12.1 (nsPE)] peripheral mean arterial pressure [MAP; 10.6 mmHg, 5.8-15.5 (sPE); 3.4 mmHg, 0.8-6.0 (nsPE)], peripheral pulse pressure [PP; 6.6 mmHg, 2.1-11.1 (sPE)], central SBP [15.8 mmHg, 10.4-21.2 (sPE); 2.9 mmHg, 0.1-5.8 (nsPE)], central DBP [8.3 mmHg, 3.9-12.6 (sPE); 2.5 mmHg, 0.2-4.8 (nsPE), central MAP [10.8 mmHg, 6.4-15.2 (sPE); 2.6 mmHg, 0.3-5.0 (nsPE)] and central PP [7.6 mmHg, 3.9-11.3 (sPE)]. Augmentation index (AIx) decreased less (15.5%, 6.3-24.6 (sPE); 9.0%, 4.2-13.6 (nsPE)] compared to uncomplicated pregnancies. Haemodynamic adaptation across pregnancy in women with GH and TGH was not different from those with uncomplicated pregnancies.

CONCLUSION

Women who develop preeclampsia show an altered, while those who develop GH or TGH demonstrate a comparable haemodynamic adaptation compared to uncomplicated pregnancies. TGH is not a benign condition.

Predicting Out-of-Office Blood Pressure in the Clinic for the Diagnosis of Hypertension in Primary Care: An Economic Evaluation

Clinical guidelines in the United States and United Kingdom recommend that individuals with suspected hypertension should have ambulatory blood pressure (BP) monitoring to confirm the diagnosis. This approach reduces misdiagnosis because of white coat hypertension but will not identify people with masked hypertension who may benefit from treatment. The Predicting Out-of-Office Blood Pressure (PROOF-BP) algorithm predicts masked and white coat hypertension based on patient characteristics and clinic BP, improving the accuracy of diagnosis while limiting subsequent ambulatory BP monitoring. This study assessed the cost-effectiveness of using this tool in diagnosing hypertension in primary care. A Markov cost-utility cohort model was developed to compare diagnostic strategies: the PROOF-BP approach, including those with clinic BP ≥130/80 mm Hg who receive ambulatory BP monitoring as guided by the algorithm, compared with current standard diagnostic strategies including those with clinic BP ≥140/90 mm Hg combined with further monitoring (ambulatory BP monitoring as reference, clinic, and home monitoring also assessed). The model adopted a lifetime horizon with a 3-month time cycle, taking a UK Health Service/Personal Social Services perspective. The PROOF-BP algorithm was cost-effective in screening all patients with clinic BP ≥130/80 mm Hg compared with current strategies that only screen those with clinic BP ≥140/90 mm Hg, provided healthcare providers were willing to pay up to £20 000 ($26 000)/quality-adjusted life year gained. Deterministic and probabilistic sensitivity analyses supported the base-case findings. The PROOF-BP algorithm seems to be cost-effective compared with the conventional BP diagnostic options in primary care. Its use in clinical practice is likely to lead to reduced cardiovascular disease, death, and disability.

Vascular aging and hypertension: Implications for the clinical application of central blood pressure

Vascular aging may be responsible for the high residual lifetime risk for hypertension in the middle-aged and elderly individuals. Increased arterial stiffness and wave reflection has been recognized as the dominant hemodynamic manifestations of vascular aging, and both are major determinants of central blood pressure (BP) and independent predictors for incident hypertension. Because central BP is strongly linearly associated with age, it can be regarded as an integrated marker for vascular aging. Central BP can be measured noninvasively using various techniques, including the convenient cuff-based oscillometric central BP monitors. Noninvasive central BP is likely better than the conventional brachial BP in association with target organ damages and long term cardiovascular outcomes. Based on the analysis of the long-term events of derivation and validation cohorts, the central BP threshold of 130/90mmHg for defining hypertension has been proposed. Recent studies suggest that the central BP strategy for confirming a diagnosis of hypertension may be more cost-effective than the conventional brachial BP strategy, and guidance of hypertension management with central BP may result in less use of medications to achieve BP control. Vascular aging-related hypertension is expected to become the dominant phenotype in many countries, especially in the Asian regions. Although noninvasive measurement of brachial BP is inaccurate and central BP has been shown to carry superior prognostic value beyond brachial BP, the use of central BP should be justified by studies comparing central blood pressure-guided therapeutic strategies with classic guidelines-guided strategies for preventing cardiovascular events. Future randomized control trials are required to support that the diagnosis and monitoring of vascular aging-related hypertension is best managed with the central BP strategy.

Is Noninvasive Brachial Systolic Blood Pressure an Accurate Estimate of Central Aortic Systolic Blood Pressure?

OBJECTIVES

Noninvasive brachial systolic blood pressure (nSBP-B) usually approaches invasive central systolic blood pressure (iSBP-C) with a high correlation. Whether nSBP-B is an accurate estimate of iSBP-C remained to be investigated. Thus, this study aimed to compare the errors of nSBP-B and noninvasive central systolic blood pressure (nSBP-C) with different techniques in estimating iSBP-C.

METHODS

Simultaneous invasive high-fidelity central aortic pressure waveforms and the noninvasive left brachial pulse volume recording (PVR) waveform were recorded in a Generation group ( N = 40) and a Validation group ( N = 100). The accuracy of the noninvasive estimates of iSBP-C obtained from analysis of the calibrated PVR waveform using the generalized transfer function (GTF), pulse waveform analysis (PWA), and N-point moving average (NPMA) methods was examined in the Validation group by calculating the mean absolute error (MAE).

RESULTS

In Generation group, the MAE was 4.6±4.1mm Hg between nSBP-B and invasive brachial SBP, and 6.8±5.5mm Hg between nSBP-B and iSBP-C. In comparison, the MAE of between iSBP-C and nSBP-C with PWA, NPMA, and GTF were 5.5±4.5, 5.8±4.9, and 5.9±5.0mm Hg, respectively. In Validation group, the MAE of nSBP-B (6.9±4.6mm Hg) for estimating iSBP-C was significantly greater than that of PWA (5.0±3.4mm Hg) and NPMA (6.1±4.4mm Hg), and GTF (6.1±4.9mm Hg). The percentage of absolute band error ≤5mm Hg was 62% for nSBP-B, 69% for GTF, 83% for PWA, and 69% for NPMA.

CONCLUSIONS

The accuracy of nSBP-B was inferior to the n SBP-C measures in estimating iSBP-C.

Practical Suitability of a Stand-Alone Oscillometric Central Blood Pressure Monitor: A Review of the Microlife WatchBP Office Central

Accumulating evidence indicates that central blood pressure (CBP) is a better cardiovascular risk predictor than brachial blood pressure (BP). Although more additional benefits of CBP-based treatment above usual hypertension treatment are to be demonstrated, the demand for implementing CBP assessment in general clinical practice is increasing. For this, the measurement procedure must be noninvasive, easy to perform, and cost- and time-efficient. Therefore, oscillometric devices with the possibility to assess CBP seem the best option. Recently, such an oscillometric BP monitor, the Microlife WatchBP Office Central, was developed, which demonstrated its high accuracy in a validation study against invasive BP measurement. Calibration errors of this device are limited because the procedure is automated, standardized, and performed at the same place of and within 30 s from pulse wave assessment. The transformation from the peripheral pulse wave to CBP is done by means of an individual-based pulse wave analysis according to a theory of arterial compliance and wave reflections. In addition, the device has demonstrated to enable a more reliable diagnosis of hypertension by CBP than by peripheral BP, with a lower frequency of over- and underdiagnosis. Altogether, the available clinical evidence suggests that the Microlife WatchBP Office Central fulfills the criteria for general clinical use.

Epidemiological Characteristics of Hypertension in the Elderly in Beijing, China

Background/Objectives

The prevalence rate of hypertension increases significantly with the aging society, and hypertension is obviously becoming a major health care concern in China. The aim of the study was to explore the epidemiological characteristics of hypertension in the elderly and to provide a basis for the prevention of hypertension.

Design

3-cross sectional studies in 2000, 2004, and 2007, respectively.

Setting

Beijing, China.

Participants

A group of 2,832, 1,828, and 2,277 elderly residents aged ≥60 years were included this study in 2000, 2004, and 2007, respectively.

Intervention

None.

Measurements

Statistical sampling techniques included cluster, stratification, and random selection. Trained staff used a comprehensive geriatric assessment questionnaire and a standard survey instrument to complete the assessments. During the person-to-person interviews, the participants’ demographic characteristics, living conditions, and health status were collected, and their blood pressure was measured.

Results

The prevalence rates (69.2%, 61.9%, and 56.0%) of hypertension and the control rates (22.6%, 16.7%, and 21.5%) lowered annually, while the awareness rates (43.7%, 55.8%, and 57.6%) of the treatment elevated annually in 2000, 2004, and 2007, respectively. There was no increase in the control rates for males (26.2%, 16.7%, and 20.8%), younger participants (28.0%, 18.4%, and 21.0%), and rural residents (19.5%, 9.6%, and 13.4%) in 2000, 2004, and 2007, respectively.

Conclusions

Our study findings indicated that the prevalence of hypertension is high in rural elderly participants, while the rates of awareness, treatment, and control were low. This suggests that effective public measures need to be developed to improve the prevention and control of hypertension.

The Novelty of the 2015 Guidelines of the Taiwan Society of Cardiology and the Taiwan Hypertension Society for the Management of Hypertension

The prevalence rate of hypertension in Asian countries grows faster than in other parts of the world, where stroke exceeds coronary heart disease in causing morbidities and mortalities. The optimal management of hypertension is therefore an especially important task in Asia. In a transparent and rigorous guideline development process, the most updated information available on the management of hypertension was summarized in the 2015 Taiwan Society of Cardiology (TSOC)/Taiwan Hypertension Society (TSH) hypertension guideline. In contradiction with the ESH/ESH joint hypertension guidelines and the 2014 Joint National Committee (JNC) report, this updated guideline suggests some different blood pressure (BP) targets. In brief, the BP target is 150/90 mm Hg for very elderly patients (≥ 80 years), 130/80 mm Hg for patients with diabetes, coronary heart disease, proteinuric chronic kidney disease or those receiving antithrombotics for stroke prevention, and 140/90 mm Hg for all the other hypertension patients with or without the aforementioned comorbidities. To facilitate the adherence to the guideline, the following was proposed: mnemonics for lifestyle modifications: S-ABCDE (Sodium restriction, Alcohol limitation, Body weight reduction, Cigarette smoking cessation, Diet adaptation, and Exercise adoption), treatment algorithm: PROCEED (Previous experience, Risk factors, Organ damage, Contraindications or unfavorable conditions, Expert's or doctor's judgment, Expenses or cost, and Delivery and compliance issue), and medication adjustment algorithm: AT GOALs (Adherence, Timing of administration, Greater doses, Other classes of drugs, Alternative combination or single-pill combination, and Lifestyle modification + Laboratory tests). In particular, the effort of translating the concept of central BP into clinical practice may stand out from all other hypertension guidelines. In summary, our guidelines may deliver useful information and guidance to clinicians in managing hypertensive patients, including the approach to a more accurate diagnosis, treatment and adjustment algorithm, and evidence-based recommendations.