Reliability of single office blood pressure measurements

Wearable Devices: Implications for Precision Medicine and the Future of Health Care

Wearable devices are integrated analytical units equipped with sensitive physical, chemical, and biological sensors capable of noninvasive and continuous monitoring of vital physiological parameters. Recent advances in disciplines including electronics, computation, and material science have resulted in affordable and highly sensitive wearable devices that are routinely used for tracking and managing health and well-being. Combined with longitudinal monitoring of physiological parameters, wearables are poised to transform the early detection, diagnosis, and treatment/management of a range of clinical conditions. Smartwatches are the most commonly used wearable devices and have already demonstrated valuable biomedical potential in detecting clinical conditions such as arrhythmias, Lyme disease, inflammation, and, more recently, COVID-19 infection. Despite significant clinical promise shown in research settings, there remain major hurdles in translating the medical uses of wearables to the clinic. There is a clear need for more effective collaboration among stakeholders, including users, data scientists, clinicians, payers, and governments, to improve device security, user privacy, data standardization, regulatory approval, and clinical validity. This review examines the potential of wearables to offer affordable and reliable measures of physiological status that are on par with FDA-approved specialized medical devices. We briefly examine studies where wearables proved critical for the early detection of acute and chronic clinical conditions with a particular focus on cardiovascular disease, viral infections, and mental health. Finally, we discuss current obstacles to the clinical implementation of wearables and provide perspectives on their potential to deliver increasingly personalized proactive health care across a wide variety of conditions.

Blood pressure variability supersedes heart rate variability as a real-world measure of dementia risk

Blood pressure variability (BPV) and heart rate variability (HRV) have been associated with Alzheimer's Disease and Related Dementias (ADRD) in rigorously controlled studies. However, the extent to which BPV and HRV may offer predictive information in real-world, routine clinical care is unclear. In a retrospective cohort study of 48,204 adults (age 54.9 ± 17.5 years, 60% female) receiving continuous care at a single center, we derived BPV and HRV from routinely collected clinical data. We use multivariable Cox models to evaluate the association of BPV and HRV, separately and in combination, with incident ADRD. Over a median 3 [2.4, 3.0] years, there were 443 cases of new-onset ADRD. We found that clinically derived measures of BPV, but not HRV, were consistently associated with incident ADRD. In combined analyses, only patients in both the highest quartile of BPV and lowest quartile of HRV had increased ADRD risk (HR 2.34, 95% CI 1.44-3.81). These results indicate that clinically derived BPV, rather than HRV, offers a consistent and readily available metric for ADRD risk assessment in a real-world patient care setting. Thus, implementation of BPV as a widely accessible tool could allow clinical providers to efficiently identify patients most likely to benefit from comprehensive ADRD screening.

The Preventiometer - reliability of a cardiovascular multi-device measurement platform and its measurement agreement with a cohort study

BACKGROUND

Multimedia multi-device measurement platforms may make the assessment of prevention-related medical variables with a focus on cardiovascular outcomes more attractive and time-efficient. The aim of the studies was to evaluate the reliability (Study 1) and the measurement agreement with a cohort study (Study 2) of selected measures of such a device, the Preventiometer.

METHODS

In Study 1 (N = 75), we conducted repeated measurements in two Preventiometers for four examinations (blood pressure measurement, pulse oximetry, body fat measurement, and spirometry) to analyze their agreement and derive (retest-)reliability estimates. In Study 2 (N = 150), we compared somatometry, blood pressure, pulse oximetry, body fat, and spirometry measurements in the Preventiometer with corresponding measurements used in the population-based Study of Health in Pomerania (SHIP) to evaluate measurement agreement.

RESULTS

Intraclass correlations coefficients (ICCs) ranged from .84 to .99 for all examinations in Study 1. Whereas bias was not an issue for most examinations in Study 2, limits of agreement for most examinations were very large compared to results of similar method comparison studies.

CONCLUSION

We observed a high retest-reliability of the assessed clinical examinations in the Preventiometer. Some disagreements between Preventiometer and SHIP examinations can be attributed to procedural differences in the examinations. Methodological and technical improvements are recommended before using the Preventiometer in population-based research.

Change in cardiometabolic risk factors in a pilot safety-net plant-based lifestyle medicine program

Introduction

Interventions emphasizing healthful lifestyle behaviors are proliferating in traditional health care settings, yet there is a paucity of published clinical outcomes, outside of pay-out-of-pocket or employee health programs.

Methods

We assessed weight, hemoglobin A1c (HbA1c), blood pressure, and cholesterol for 173 patients of the Plant-Based Lifestyle Medicine Program piloted in a New York City safety-net hospital. We used Wilcoxon signed-rank tests to assess changes in means, from baseline to six-months, for the full sample and within baseline diagnoses (i.e., overweight or obesity, type 2 diabetes, prediabetes, hypertension, hyperlipidemia). We calculated the percentage of patients with clinically meaningful changes in outcomes for the full sample and within diagnoses.

Findings

The full sample had statistically significant improvements in weight, HbA1c, and diastolic blood pressure. Patients with prediabetes or overweight or obesity experienced significant improvements in weight and those with type 2 diabetes had significant improvements in weight and HbA1c. Patients with hypertension had significant reductions in diastolic blood pressure and weight. Data did not show differences in non-high-density lipoprotein cholesterol (non-HDL-C), but differences in low-density lipoprotein cholesterol (LDL-C) were approaching significance for the full sample and those with hyperlipidemia. The majority of patients achieved clinically meaningful improvements on all outcomes besides systolic blood pressure.

Conclusion

Our study demonstrates that a lifestyle medicine intervention within a traditional, safety-net clinical setting improved biomarkers of cardiometabolic disease. Our findings are limited by small sample sizes. Additional large-scale, rigorous studies are needed to further establish the effectiveness of lifestyle medicine interventions in similar settings.

Sources of automatic office blood pressure measurement error: a systematic review

OBJECTIVE

Accurate and reliable blood pressure (BP) measurement is important for the prevention and treatment of hypertension. The oscillometric-based automatic office blood pressure measurement (AOBPM) is widely used in hospitals and clinics, but measurement errors are common in BP measurements. There is a lack of systematic review of the sources of measurement errors.

APPROACH

A systematic review of all existing research on sources of AOBPM errors. A search strategy was designed in six online databases, and all the literature published before October 2021 was selected. Those studies that used the AOBPM device to measure BP from the upper arm of subjects were included.

MAIN RESULTS

A total of 1365 studies were screened, and 224 studies were included in this final review. They investigated 22 common error sources with clinical AOBPM. Regarding the causes of BP errors, this review divided them into the following categories: the activities before measurement, patient's factors, measurement environment, measurement procedure, and device settings. 13 sources caused increased systolic and diastolic BP (SBP and DBP), 2 sources caused the decrease in SBP and DBP, only 1 source had no significant effect on BPs, and the other errors had a non-uniform effect (either increase or decrease in BPs). The error ranges for SBP and DBP were -14 to 33 mmHg and -6 to 19 mmHg, respectively.

SIGNIFICANCE

The measurement accuracy of AOBPM is susceptible to the influence of measurement factors. Interpreting BP readings need to be treated with caution in clinical measurements. This review made comprehensive evidence for the need for standardized BP measurements and provided guidance for clinical practitioners when measuring BP with AOBPM devices.

Replacing salt with low-sodium salt substitutes (LSSS) for cardiovascular health in adults, children and pregnant women

BACKGROUND

Elevated blood pressure, or hypertension, is the leading cause of preventable deaths globally. Diets high in sodium (predominantly sodium chloride) and low in potassium contribute to elevated blood pressure. The WHO recommends decreasing mean population sodium intake through effective and safe strategies to reduce hypertension and its associated disease burden. Incorporating low-sodium salt substitutes (LSSS) into population strategies has increasingly been recognised as a possible sodium reduction strategy, particularly in populations where a substantial proportion of overall sodium intake comes from discretionary salt. The LSSS contain lower concentrations of sodium through its displacement with potassium predominantly, or other minerals. Potassium-containing LSSS can potentially simultaneously decrease sodium intake and increase potassium intake.  Benefits of LSSS include their potential blood pressure-lowering effect and relatively low cost. However, there are concerns about potential adverse effects of LSSS, such as hyperkalaemia, particularly in people at risk, for example, those with chronic kidney disease (CKD) or taking medications that impair potassium excretion.

OBJECTIVES

To assess the effects and safety of replacing salt with LSSS to reduce sodium intake on cardiovascular health in adults, pregnant women and children.

SEARCH METHODS

We searched MEDLINE (PubMed), Embase (Ovid), Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science Core Collection (Clarivate Analytics), Cumulative Index to Nursing and Allied Health Literature (CINAHL, EBSCOhost), ClinicalTrials.gov and WHO International Clinical Trials Registry Platform (ICTRP) up to 18 August 2021, and screened reference lists of included trials and relevant systematic reviews. No language or publication restrictions were applied.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and prospective analytical cohort studies in participants of any age in the general population, from any setting in any country. This included participants with non-communicable diseases and those taking medications that impair potassium excretion. Studies had to compare any type and method of implementation of LSSS with the use of regular salt, or no active intervention, at an individual, household or community level, for any duration.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles, abstracts and full-text articles to determine eligibility; and extracted data, assessed risk of bias (RoB) using the Cochrane RoB tool, and assessed the certainty of the evidence using GRADE. We stratified analyses by adults, children (≤ 18 years) and pregnant women. Primary effectiveness outcomes were change in diastolic and systolic blood pressure (DBP and SBP), hypertension and blood pressure control; cardiovascular events and cardiovascular mortality were additionally assessed as primary effectiveness outcomes in adults. Primary safety outcomes were change in blood potassium, hyperkalaemia and hypokalaemia.

MAIN RESULTS

We included 26 RCTs, 16 randomising individual participants and 10 randomising clusters (families, households or villages). A total of 34,961 adult participants and 92 children were randomised to either LSSS or regular salt, with the smallest trial including 10 and the largest including 20,995 participants. No studies in pregnant women were identified. Studies included only participants with hypertension (11/26), normal blood pressure (1/26), pre-hypertension (1/26), or participants with and without hypertension (11/26). This was unknown in the remaining studies. The largest study included only participants with an elevated risk of stroke at baseline. Seven studies included adult participants possibly at risk of hyperkalaemia. All 26 trials specifically excluded participants in whom an increased potassium intake is known to be potentially harmful. The majority of trials were conducted in rural or suburban settings, with more than half (14/26) conducted in low- and middle-income countries. The proportion of sodium chloride replacement in the LSSS interventions varied from approximately 3% to 77%. The majority of trials (23/26) investigated LSSS where potassium-containing salts were used to substitute sodium. In most trials, LSSS implementation was discretionary (22/26). Trial duration ranged from two months to nearly five years.  We assessed the overall risk of bias as high in six trials and unclear in 12 trials. LSSS compared to regular salt in adults: LSSS compared to regular salt probably reduce DBP on average (mean difference (MD) -2.43 mmHg, 95% confidence interval (CI) -3.50 to -1.36; 20,830 participants, 19 RCTs, moderate-certainty evidence) and SBP (MD -4.76 mmHg, 95% CI -6.01 to -3.50; 21,414 participants, 20 RCTs, moderate-certainty evidence) slightly.  On average, LSSS probably reduce non-fatal stroke (absolute effect (AE) 20 fewer/100,000 person-years, 95% CI -40 to 2; 21,250 participants, 3 RCTs, moderate-certainty evidence), non-fatal acute coronary syndrome (AE 150 fewer/100,000 person-years, 95% CI -250 to -30; 20,995 participants, 1 RCT, moderate-certainty evidence) and cardiovascular mortality (AE 180 fewer/100,000 person-years, 95% CI -310 to 0; 23,200 participants, 3 RCTs, moderate-certainty evidence) slightly, and probably increase blood potassium slightly (MD 0.12 mmol/L, 95% CI 0.07 to 0.18; 784 participants, 6 RCTs, moderate-certainty evidence), compared to regular salt.  LSSS may result in little to no difference, on average, in hypertension (AE 17 fewer/1000, 95% CI -58 to 17; 2566 participants, 1 RCT, low-certainty evidence) and hyperkalaemia (AE 4 more/100,000, 95% CI -47 to 121; 22,849 participants, 5 RCTs, moderate-certainty evidence) compared to regular salt. The evidence is very uncertain about the effects of LSSS on blood pressure control, various cardiovascular events, stroke mortality, hypokalaemia, and other adverse events (very-low certainty evidence). LSSS compared to regular salt in children: The evidence is very uncertain about the effects of LSSS on DBP and SBP in children. We found no evidence about the effects of LSSS on hypertension, blood pressure control, blood potassium, hyperkalaemia and hypokalaemia in children.

AUTHORS' CONCLUSIONS

When compared to regular salt, LSSS probably reduce blood pressure, non-fatal cardiovascular events and cardiovascular mortality slightly in adults. However, LSSS also probably increase blood potassium slightly in adults. These small effects may be important when LSSS interventions are implemented at the population level. Evidence is limited for adults without elevated blood pressure, and there is a lack of evidence in pregnant women and people in whom an increased potassium intake is known to be potentially harmful, limiting conclusions on the safety of LSSS in the general population. We also cannot draw firm conclusions about effects of non-discretionary LSSS implementations. The evidence is very uncertain about the effects of LSSS on blood pressure in children.

Use of unattended automated office blood pressure in Utah primary care clinics

AIM

Unattended automated office blood pressure (BP) measurement (u-AOBP) improves office BP measurement accuracy and reduces white-coat BP elevation. u-AOBP is recommended as the preferred office BP measurement technique by multiple hypertension guidelines. This study examines utilization, performance, and potential barriers to implementation of u-AOBP in Utah primary care clinics following 5 years of promotional efforts by the Utah Million Hearts Coalition (UMHC).

METHODS

An online questionnaire was administered to 285 Utah primary care clinics to evaluate self-reported use of u-AOBP and u-AOBP technique, interpretation of results, and perceived barriers to implementation.

RESULTS

Seventy-nine of 285 clinics (27.7%) completed the full questionnaire. Fifty-nine clinics (74.7%) use u-AOBP. Nearly 65% first learned about u-AOBP through UMHC promotional efforts rather than from the medical literature. One-half of these clinics noted no significant barriers to u-AOBP implementation, and over 80% noted no reduction in medical staff productivity. However, important knowledge deficits concerning correct u-AOBP performance and interpretation of results were apparent from answers to the questionnaire.

CONCLUSION

After 5 years of UMHC promotional efforts, at least 20% of the 285 Utah primary care clinics invited to take the questionnaire and 75% of the 79 clinics completing the survey have incorporated u-AOBP and found it feasible in a primary care setting. Ongoing promotion of u-AOBP implementation at the local and regional level is required to extend its utilization. Effective, accessible educational materials and local technical assistance from public health and community partners are needed to correct knowledge and performance deficits to optimize u-AOBP utilization in primary care.

Variability independent of mean blood pressure as a real-world measure of cardiovascular risk

Background

Individual-level blood pressure (BP) variability, independent of mean BP levels, has been associated with increased risk for cardiovascular events in cohort studies and clinical trials using standardized BP measurements. The extent to which BP variability relates to cardiovascular risk in the real-world clinical practice setting is unclear. We sought to determine if BP variability in clinical practice is associated with adverse cardiovascular outcomes using clinically generated data from the electronic health record (EHR).

Methods

We identified 42,482 patients followed continuously at a single academic medical center in Southern California between 2013 and 2019 and calculated their systolic and diastolic BP variability independent of the mean (VIM) over the first 3 years of the study period. We then performed multivariable Cox proportional hazards regression to examine the association between VIM and both composite and individual outcomes of interest (incident myocardial infarction, heart failure, stroke, and death).

Findings

Both systolic (HR, 95% CI 1.22, 1.17-1.28) and diastolic VIM (1.24, 1.19-1.30) were positively associated with the composite outcome, as well as all individual outcome measures. These findings were robust to stratification by age, sex and clinical comorbidities. In sensitivity analyses using a time-shifted follow-up period, VIM remained significantly associated with the composite outcome for both systolic (1.15, 1.11-1.20) and diastolic (1.18, 1.13-1.22) values.

Interpretation

VIM derived from clinically generated data remains associated with adverse cardiovascular outcomes and represents a risk marker beyond mean BP, including in important demographic and clinical subgroups. The demonstrated prognostic ability of VIM derived from non-standardized BP readings indicates the utility of this measure for risk stratification in a real-world practice setting, although residual confounding from unmeasured variables cannot be excluded.

Funding

This study was funded in part by National Institutes of Health grants R01-HL134168, R01-HL131532, R01-HL143227, R01-HL142983, U54-AG065141; R01-HL153382, K23-HL136853, K23-HL153888, and K99-HL157421; China Scholarship Council grant 201806260086; Academy of Finland (Grant no: 321351); Emil Aaltonen Foundation; Finnish Foundation for Cardiovascular Research.

[Drivers and scorecards to improve hypertension control in primary care practice: Recommendations from the HEARTS in the Americas Innovation GroupFactores impulsores y métodos de puntuación para mejorar el control de la hipertensión en la práctica clínica de la atención primaria: recomendaciones del grupo de innovación de HEARTS en las Américas]

Fundamentos.

As doenças cardiovasculares (DCV) são as principais causas de morbimortalidade nas Américas, e a hipertensão arterial (HÁ) é o fator de risco modificável mais importante. Porém, as taxas de controle da HA continuam baixas, e a mortalidade por DCV está estagnada ou aumentando após décadas de redução contínua. Em 2016, a Organização Mundial da Saúde (OMS) lançou o pacote de medidas técnicas HEARTS para melhorar o controle da HA. A Organização Pan-Americana da Saúde (OPAS) criou a iniciativa HEARTS nas Américas para melhorar a gestão do risco cardiovascular (RCV), com ênfase no controle da HA. Até agora, essa iniciativa foi implementada em 21 países.

Métodos.

Para impulsionar a implementação, recrutou-se um grupo multidisciplinar de profissionais para selecionar impulsionadores-chave do controle da HA com base em evidências e elaborar um scorecard completo para monitorar sua implementação em unidades de atenção primária à saúde (APS). O grupo estudou sistemas de saúde com alto desempenho que haviam conseguido atingir um alto nível de controle da HA por meio de programas de melhoria da qualidade focados em medidas específicas de processo, com feedback regular para os profissionais das unidades de saúde.

Resultados.

Os oito fatores impulsionadores incluídos na seleção final foram categorizados em cinco domínios principais: (1) diagnóstico (exatidão da medição da pressão arterial e avaliação do RCV); (2) tratamento (protocolo padronizado de tratamento e intensificação do tratamento); (3) continuidade do cuidado e acompanhamento; (4) modelo de atenção (atendimento baseado em equipe, renovação da prescrição); e (5) sistema de avaliação do desempenho. Em seguida, os fatores impulsionadores e as recomendações foram transformados em medidas de processo, gerando dois scorecards inter-relacionados integrados ao sistema de monitoramento e avaliação da Iniciativa HEARTS nas Américas.

Interpretação.

O foco nesses impulsionadores-chave da HA e nos scorecards resultantes orientará o processo de melhoria da qualidade para atingir as metas de controle, a nível populacional, dos centros de saúde participantes nos países que estão implementando a iniciativa HEARTS.

[Drivers and scorecards to improve hypertension control in primary care practice: Recommendations from the HEARTS in the Americas Innovation GroupFatores impulsionadores e scorecards para melhorar o controle da hipertensão arterial na atenção primária: recomendações do Grupo de Inovação da Iniciativa HEARTS nas Américas]

Antecedentes.

Las enfermedades cardiovasculares (ECV) son la principal causa de morbilidad y mortalidad en la Región de las Américas y la hipertensión es el factor de riesgo modificable asociado más importante. Sin embargo, las tasas de control de la hipertensión siguen siendo bajas y la mortalidad por ECV está estancada o en aumento después de décadas de reducción continua. En el 2016, la Organización Mundial de la Salud (OMS) presentó el paquete técnico HEARTS para mejorar el control de la hipertensión. La Organización Panamericana de la Salud (OPS) diseñó la iniciativa HEARTS en las Américas para mejorar el control del riesgo de ECV, que hace hincapié en el control de la hipertensión y que, hasta la fecha, se ha implementado en 21 países.

Métodos.

Para avanzar en la implementación, se creó un grupo interdisciplinario de profesionales de la salud con el objetivo de seleccionar los factores impulsores claves del control de la hipertensión basados en la evidencia y diseñar un método de puntuación integral para dar seguimiento a su implementación en los centros de atención de salud primaria (APS). El grupo estudió los sistemas de salud de alto desempeño que logran un control elevado de la hipertensión mediante programas de mejora de la calidad que se centran en medidas específicas con respecto a los procesos, con retroalimentación regular a los prestadores en los centros de salud.

Resultados.

Los ocho factores impulsores finales seleccionados se clasificaron en cinco dominios principales: 1) diagnóstico (exactitud de la medición de la presión arterial y evaluación del riesgo de ECV); 2) tratamiento (protocolo de tratamiento e intensificación del tratamiento estandarizados); 3) continuidad de la atención y seguimiento; 4) sistema de prestación del tratamiento (atención basada en un trabajo en equipo, reposición de la medicación) y 5) sistema para la evaluación del desempeño. Los factores impulsores y las recomendaciones se tradujeron en medidas con respecto a los procesos, lo que llevó a dos métodos de puntuación integrados e interconectados en el sistema de seguimiento y evaluación del programa HEARTS en las Américas.

Conclusiones.

El enfoque que se centra en estos factores impulsores clave de la hipertensión y los métodos de puntuación resultantes servirá de guía para el proceso de mejora de la calidad con objeto de alcanzar los objetivos de control a nivel poblacional en los centros de salud participantes de los países que implementan el programa HEARTS.

Drivers and scorecards to improve hypertension control in primary care practice: Recommendations from the HEARTS in the Americas Innovation Group

Background

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in the Americas, and hypertension is the most significant modifiable risk factor. However, hypertension control rates remain low, and CVD mortality is stagnant or rising after decades of continuing reduction. In 2016, the World Health Organization (WHO) launched the HEARTS technical package to improve hypertension control. The Pan American Health Organization (PAHO) designed the HEARTS in the Americas Initiative to improve CVD risk management, emphasizing hypertension control, to date implemented in 21 countries.

Methods

To advance implementation, an interdisciplinary group of practitioners was engaged to select the key evidence-based drivers of hypertension control and to design a comprehensive scorecard to monitor their implementation at primary care health facilities (PHC). The group studied high-performing health systems that achieve high hypertension control through quality improvement programs focusing on specific process measures, with regular feedback to providers at health facilities.

Findings

The final selected eight drivers were categorized into five main domains: (1) diagnosis (blood pressure measurement accuracy and CVD risk evaluation); (2) treatment (standardized treatment protocol and treatment intensification); (3) continuity of care and follow-up; (4) delivery system (team-based care, medication refill), and (5) system for performance evaluation. The drivers and recommendations were then translated into process measures, resulting in two interconnected scorecards integrated into the HEARTS in the Americas monitoring and evaluation system.

Interpretation

Focus on these key hypertension drivers and resulting scorecards, will guide the quality improvement process to achieve population control goals at the participating health centers in HEARTS implementing countries.

Funding

No funding to declare.

Effectiveness of Physical Activity and Exercise on Ambulatory Blood Pressure in Adults with Resistant Hypertension: A Systematic Review and Meta-Analysis

Introduction

Resistant hypertension (RHT) is a phenotype of hypertension that is challenging to manage by medications alone. While high grade evidence supports physical activity (PA) and exercise to reduce blood pressure (BP) in hypertension, it is unclear whether these are also effective for RHT.

Aims

To determine the quality of evidence for the effectiveness of PA and exercise and the change of magnitude of 24-hour ambulatory BP (24hABP) in adults with RHT.

Methods

Scopus, MEDLINE, CINHAL, Web of Science, Embase and SPORTDiscus databases were searched. Cochrane risk of bias tools, Review Manager and Grading of the Recommendation Assessment, Development and Evaluation were used to assess the methodological quality, the clinical heterogeneity and quality of the evidence.

Results

Four studies comprising 178 individuals in total were included. A meta-analysis with random effects showed decreased 24hABP. The experimental group demonstrated grater mean differences for 24hABP following the PA and exercise programmes (systolic − 9.88 mmHg, 95% CI: − 17.62, − 2.14, I² = 72%, p = 0.01; diastolic − 6.24 mmHg, 95% CI: − 12.65, 0.17, I² = 93%,p = 0.06); and aerobic exercise (systolic − 12.06 mmHg, 95% CI: − 21.14, − 2.96, I² = 77%, p = 0.009, diastolic − 8.19 mmHg, 95% CI: − 14.83, − 1.55, I² = 92% ,p = 0.02). In the included studies, indirectness and publication bias were ‘moderate’ while inconsistency and imprecision were rated as ‘low’. Thus, the overall quality of the evidence was considered to be ‘low’.

Conclusions

Low certainty evidence suggests that PA and aerobic exercise added to usual care may be more effective in 24hABP reduction in RHT than usual care alone.

Registration

PROSPERO—2019 CRD42019147284 (21.11.2019).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40292-022-00517-6.

Effects of Magnesium Citrate, Magnesium Oxide, and Magnesium Sulfate Supplementation on Arterial Stiffness: A Randomized, Double‐Blind, Placebo‐Controlled Intervention Trial

Background

Magnesium supplements may have beneficial effects on arterial stiffness. Yet, to our knowledge, no head‐to‐head comparison between various magnesium formulations in terms of effects on arterial stiffness has been performed. We assessed the effects of magnesium citrate supplementation on arterial stiffness and blood pressure and explored whether other formulations of magnesium have similar effects.

Methods and Results

In this randomized trial, subjects who were overweight and slightly obese received either magnesium citrate, magnesium oxide, magnesium sulfate, or placebo for 24 weeks. The total daily dose of magnesium was 450 mg/d. The primary outcome was carotid‐to‐femoral pulse wave velocity, which is the gold standard method for measuring arterial stiffness. Secondary outcomes included blood pressure and plasma and urine magnesium. Overall, 164 participants (mean±SD age, 63.2±6.8 years; 104 [63.4%] women) were included. In the intention‐to‐treat analysis, neither magnesium citrate nor the other formulations had an effect on carotid‐to‐femoral pulse wave velocity or blood pressure at 24 weeks compared with placebo. Magnesium citrate increased plasma (+0.04 mmol/L; 95% CI, +0.02 to +0.06 mmol/L) and urine magnesium (+3.12 mmol/24 h; 95% CI, +2.23 to +4.01 mmol/24 h) compared with placebo. Effects on plasma magnesium were similar among the magnesium supplementation groups, but magnesium citrate led to a more pronounced increase in 24‐hour urinary magnesium excretion than magnesium oxide or magnesium sulfate. One serious adverse event was reported, which was considered unrelated to the study treatment.

Conclusions

Oral magnesium citrate supplementation for 24 weeks did not significantly change arterial stiffness or blood pressure. Magnesium oxide and magnesium sulfate had similar nonsignificant effects.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03632590.

Simplified hypertension screening approaches with low misclassification and high efficiency in the United States, Nepal, and India

Standard triplicate blood pressure (BP) measurements pose time barriers to hypertension screening, especially in resource‐limited settings. We assessed the implications of simplified approaches using fewer measurements with adults (≥18 years old) not using anti‐hypertensive medications from the US National Health and Nutrition Examination Survey 1999‐2016 (n = 30 614), and two datasets from May Measurement Month 2017‐2018 (n = 14 795 for Nepal and n = 6 771 for India). We evaluated the proportion of misclassification of hypertension when employing the following simplified approaches: using only 1st BP, only 2nd BP, 2nd if 1st BP in a given range (otherwise using 1st), and average of 1st and 2nd BP. Hypertension was defined as average of 2nd and 3rd systolic BP ≥140 and/or diastolic BP ≥90 mm Hg. Using only the 1st BP, the proportion of missed hypertension ranged from 8.2%–12.1% and overidentified hypertension from 4.3%–9.1%. Using only 2nd BP reduced the misclassification considerably (corresponding estimates, 4.9%–6.4% for missed hypertension and 2.0%–4.4% for overidentified hypertension) but needed 2nd BP in all participants. Using 2nd BP if 1st BP ≥130/80 demonstrated similar estimates of missed hypertension (3.8%–8.1%) and overidentified hypertension (2.0%–3.9%), but only required a 2nd BP in 33.8%–59.8% of participants. In conclusion, a simplified approach utilizing 1st BP supplemented by 2nd BP in some individuals has low misclassification rates and requires approximately half of the total number of measurements compared to the standard approach, and thus can facilitate screening in resource‐constrained settings.

Accuracy of abbreviated protocols for unattended automated office blood pressure measurements, a retrospective study

Background

Blood pressure measurement (BPM) is one of the most often performed procedures in clinical practice, but especially office BPM is prone to errors. Unattended automated office BPM (AOBPM) is somewhat standardised and observer-independent, but time and space consuming. We aimed to assess whether an AOBPM protocol can be abbreviated without losing accuracy.

Design

In our retrospective single centre study, we used all AOBPM (AOBPM protocol of the SPRINT study), collected over 14 months. Three sequential BPM (after 5 minutes of rest, spaced 2 minutes) were automatically recorded with the patient alone in a quiet room resulting in three systolic and diastolic values. We compared the mean of all three (RefProt) with the mean of the first two (ShortProtA) and the single first BPM (ShortProtB).

Results

We analysed 413 AOBPM sets from 210 patients. Mean age was 52±16 years. Mean values for RefProt were 128.3/81.3 mmHg, for ShortProtA 128.4/81.4 mmHg, for ShortProtB 128.8/81.4 mmHg. Mean difference and limits of agreement for RefProt vs. ShortProtA and ShortProtB were -0.1±4.2/-0.1±2.8 mmHg and -0.5±8.1/-0.1±5.3 mmHg, respectively. With ShortProtA, 83% of systolic and 92% of diastolic measurements were within 2 mmHg from RefProt (67/82% for ShortProtB). ShortProtA or ShortProtB led to no significant hypertensive reclassifications in comparison to RefProt (p-values 0.774/1.000/1.000/0.556).

Conclusion

Based on our results differences between the RefProt and ShortProtA are minimal and within acceptable limits of agreement. Therefore, the automated procedure may be shorted from 3 to 2 measurements, but a single measurement is insufficient.

How Should We Measure and Deal with Office Blood Pressure in 2021?

Arterial hypertension is a major risk factor for cardiovascular disease worldwide. Office blood pressure measurements (OBPMs) are still recommended for diagnosis and follow-up by all major guidelines; however, the recommended procedures differ significantly. In analogy, major outcome studies usually apply OBPMs, again, with a variety of procedures. This variety of OBPM procedures complicates the comparability between studies and challenges daily clinical practice. In this narrative review, we compile the most recent recommendations for office blood pressure measurement together with the major limitations and strategies and how these could be overcome.

How should we measure blood pressure? Implications of the fourth blood pressure measurement in office blood pressure

According to the European Hypertension Guidelines regarding office blood pressure measurements (OBPMs), the mean between second/third or third/fourth OBPM should be taken if the first two readings differ by ≤10 or >10 mmHg, respectively. Our aim was to explore the value of the fourth OBPM and determine whether a simplified OBPM procedure is feasible without loss of quality. In this cross‐sectional study, four standard OBPMs were taken. The mean of the second/third OBPM (S2S3/D2D3) and third/fourth OBPM (S3S4/D3D4) for systolic/diastolic values was calculated. Correlation, agreement, and differences regarding BP classification were explored for the entire cohort and subsets with a difference between the first/second OBPM (S1S2/D1D2) ≤10 and >10 mmHg. Overall (n = 802) and for the subsets with an S1S2 (n = 596) and D1D2 (n = 742) difference ≤10 mmHg, S3S4/D3D4 was in median 0.5 mmHg lower than S2S3/D2D3, respectively (p < .0005 for all). In participants with an S1S2 (n = 206) and D1D2 (n = 60) difference >10 mmHg, S3S4/D3D4 differed numerically from S2S3/D2D3, respectively (p > .1 for all). Overall and for all subsets with an S1S2/D1D2 difference ≤10/>10 mmHg, less subjects were numerically classified as hypertensive with S3S4/D3D4 than with S2S3/D2D3 (p > .04), but BP reclassification occurred in both directions in 1.0%‐10.0%, depending on the cohort. In conclusion, the third/fourth OBPM results in lower BP values than the second/third measurement, regardless of the difference between first/second OBPM, whereby BP reclassifications occurred in both directions. Therefore, the cutoff of >10 versus ≤10mmHg difference between first/second OBPM to implement a fourth BPM harbors the risk of distorted results. We therefore recommend using the second/third BPM for standardized OBPM.

Trial registration: Registered on clinicaltrials.gov (NCT02552030).

Prevalence of high blood pressure under 2017 ACC/AHA guidelines: a systematic review and meta-analysis

To understand the prevalence of high blood pressure among the general adult population under the new diagnostic criteria. PubMed and Embase databases were systematically searched. Two investigators independently performed data extraction and quality assessment, and the disagreements were resolved by consensus with a third investigator. The random-effects model was performed to pool the prevalence of high blood pressure among the population. Subgroup and meta-regression analyses were performed to explore the source of heterogeneity. The study protocol has been registered with PROSPERO, number CRD42019147330. In total, 52 articles included in the meta-analysis with a total of 54 studies. An obvious increase in the prevalence of high blood pressure was identified by the application of new diagnostic criteria. The pooled prevalence of high blood pressure among the population was 53.01% (95% confidence interval 51.13-54.88%). Subgroup analysis showed that the WHO region, national, and age could significantly influence the prevalence of hypertension (P < 0.01). Meta-regression analyses revealed that study quality and sex ratio (male, %) did not contribute to the heterogeneity of the results (P > 0.05). The sensitivity analysis showed that the results were stable. With the use of new diagnostic criteria, the prevalence of high blood pressure has shown an upward trend, especially in Europe countries. Prevention and control measures should focus more on improving cardiovascular and cerebrovascular status in Europe countries. Standard electronic blood pressure monitors were recommended for use in future studies, and at least two more readings should be taken during a visit.

Blood pressure measurement protocol determines hypertension phenotypes in a Middle Eastern population

Clinic blood pressure (BP) measurement remains a crucial step in managing hypertension. While the number of measures recorded in different settings varies, with typically 1-3 measures, there has been no prior justification for the actual number of measures required. We investigated the pattern of BP variability over 5 consecutive automated readings (R1-R5) and the influence of patient characteristics on this pattern to identify the phenotype of hypertension in a Middle Eastern population. There were 1389 outpatients (51% men, 49% women), age range (18-87 y) who had 5 unattended automated consecutive BP measurements with one-minute intervals using the validated Datascope Mindray Passport V Monitor with the patient blinded from the results. Mean (±SEM) SBP for R1 (136.0 ± 2 mm Hg) was similar to R2 (136.2 ± 2 mm Hg). Thereafter SBP progressively declined till R5 by total of 5.5 mm Hg. The SBP decline was less (4.2 mm Hg) in older (>50 years) vs younger participants (8.1 mm Hg; P < .001) and was blunted in diabetic and hypertensive participants. Overall, 43% of participants had R2 > R1, and 24% additionally had R5 > R1. Age was a strong independent predictor of having both R2 > R1 and R5 > R1, as well as diabetes. Diastolic blood pressure (DBP) decreased by average 2.8 mm Hg from R1 to R5. Females had a 5-fold greater total decline in DBP vs males (P < .001). Using the mean of 5 BP measures resulted in fewer participants being classified as hypertensive (36% of the population) compared to using one measurement (46%), or established BP guidelines which use different combinations of R1-R3 (37%-42%). Our findings in a Middle Eastern population highlight the importance of the BP measurement protocol in combination with patient characteristics in determining whether a patient is diagnosed with hypertension. Protocols that rely on different combinations of only 3 measures (R1-3) will classify more participants as hypertensive, compared to using 5 measures or disregarding a high R2.

Development and implementation of blood pressure screening and referral guidelines for German community pharmacists

Involvement of community pharmacists in the detection and control of hypertension improves patient care. However, current European or North‐American guidelines do not provide specific guidance how to implement collaboration between pharmacists and physicians, especially when and how to refer patients with undetected or uncontrolled hypertension to a physician. The German Society of Cardiology and the ABDA – Federal Union of German Associations of Pharmacists developed and tested referral recommendations for community pharmacists, embedded in two guideline worksheets. The project included a guideline‐directed blood pressure (BP) measurement and recommendations when patients should be referred to their physician. A “red flag” referral within 4 weeks was recommended when SBP was >140 mm Hg or DBP >90 mm Hg (for subjects <80 years), and >160 mm Hg or >90 mm Hg (≥80 years) in undetected individuals, or >130 mm Hg or >80 mm Hg (<65 years) and >140 mm Hg or >80 mm Hg (≥65 years) in treated patients. BP was measured in 187 individuals (86 with known hypertension, mean [±SD] age 62 ± 15 years, 64% female, and 101 without known hypertension, 47 ± 16 years, 75% female) from 17 community pharmacies. In patients with hypertension, poorly controlled BP was detected in 55% (n = 47) and were referred. A total of 16/101 subjects without a history of hypertension were referred to their physician because of uncontrolled BP. Structured BP testing in pharmacies identified a significant number of subjects with undetected/undiagnosed hypertension and patients with poorly controlled BP. Community pharmacists could play a significant role in collaboration with physicians to improve the management of hypertension.

Standardized reporting of co-morbidity outcome after bariatric surgery: low compliance with the ASMBS outcome reporting standards despite ease of use

BACKGROUND

Despite the publication of the American Society for Metabolic and Bariatric Surgery (ASMBS) Outcome Reporting Standards in 2015, there is still a great variety in definitions used for reporting remission of co-morbidities after bariatric surgery. This hampers meaningful comparison of results.

OBJECTIVE

To assess compliance with the ASMBS standards in current literature, and to evaluate use of the standards by applying them in a report on the outcomes of 5 co-morbidities after bariatric surgery.

SETTING

Two clinics of the Dutch Obesity Clinic, location Den Haag and Velp, and three affiliated hospitals: Haaglanden Medical Center in Den Haag, Groene Hart Hospital in Gouda, and Vitalys Clinic in Velp.

METHODS

A systematic search in PubMed was conducted to identify studies using the ASMBS standards. Besides, the standards were applied to a cohort of patients who underwent a primary bariatric procedure between November 2016 and June 2017. Outcomes of co-morbidities were determined at 6 and 12 months after surgery.

RESULTS

Ten previous studies applying ASMBS definitions were identified by the search, including 6 studies using portions of the definitions, and 4 using complete definitions for 3 co-morbidities or in a small population. In this study, the standards were applied to 1064 patients, of whom 796 patients (75%) underwent Roux-en-Y gastric bypass and 268 patients (25%) underwent sleeve gastrectomy. At 12 months, complete remission of diabetes (glycosylated hemoglobin <6%, off medication) was reached in 63%, partial remission (glycosylated hemoglobin 6%-6.4%, off medication) in 7%, and improvement in 28% of patients (n = 232/248, 94%). Complete remission of hypertension (normotensive, off medication) was noted in 8%, partial remission (prehypertensive, off medication) in 23% and improvement in 63% (n = 397/412, 96%). Remission rate for dyslipidemia (normal nonhigh-density lipoprotein, off medication) was 57% and improvement rate was 19% (n = 129/133, 97%). Resolution of gastroesophageal reflux disease (no symptoms, off medication) was observed in 54% (n = 265/265). Obstructive sleep apnea syndrome improved in 90% (n = 157/169, 93%).

CONCLUSIONS

Compliance with the ASMBS standards is low, despite ease of use. Standardized definitions provided by the ASMBS guideline could be used in future research to enable comparison of outcomes of different studies and surgical procedures.

Preference of blood pressure measurement methods by primary care doctors in Hong Kong: a cross-sectional survey

Background

Hypertension is the most common chronic disease and is the leading cause of morbidity and mortality. Its screening, diagnosis, and management depend heavily on accurate blood pressure (BP) measurement. It is recommended that the diagnosis of hypertension should be confirmed or corroborated by out-of-office BP values, measured using ambulatory BP monitoring (ABPM) and home BP monitoring (HBPM). When office BP is used, automated office BP (AOBP) measurement method, which automatically provides an average of 3–5 BP readings, should be preferred. This study aimed to describe the BP measurement methods commonly used by doctors in primary care in Hong Kong, to screen, diagnose, and manage hypertensive patients.

Methods

In this cross-sectional survey, all doctors registered in the Hong Kong “Primary Care Directory” were mailed a questionnaire, asking their preferred BP-measuring methods to screen, diagnose, and manage hypertensive patients. Furthermore, we also elicited information on the usual number of office BP or HBPM readings obtained, to diagnose or manage hypertension.

Results

Of the 1738 doctors included from the directory, 445 responded. Manual measurement using a mercury or aneroid device was found to be the commonest method to screen (63.1%), diagnose (56.4%), and manage (72.4%) hypertension. There was a significant underutilisation of ABPM, with only 1.6% doctors using this method to diagnose hypertension. HBPM was used by 22.2% and 56.8% of the respondents to diagnose and manage hypertension, respectively. A quarter (26.7%) of the respondents reported using only one in-office BP reading, while around 40% participants reported using ≥12 HBPM readings. Doctors with specialist qualification in family medicine were more likely to use AOBP in clinics and to obtain the recommended number of office BP readings for diagnosis and management of hypertension.

Conclusion

Primary Care doctors in Hong Kong prefer to use manual office BP values, measured using mercury or aneroid devices, to screen, diagnose, and manage hypertension, highlighting a marked underutilisation of AOBP and out-of-office BP measuring techniques, especially that of ABPM. Further studies are indicated to understand the underlying reasons and to minimise the gap between real-life clinical practice and those recommended, based on scientific advances.

Trial registration

Clinicaltrial.gov; ref. no.: NCT03926897.

Screen-based media use and blood pressure in preschool-aged children: A prospective study in the Odense Child Cohort

Aims: To examine prospective and cross-sectional associations between screen time and blood pressure (BP) in preschool children. Methods: The Odense Child Cohort study started in January 2010. Children who were born in the municipality of Odense underwent a clinical examination at 3 and 5 years of age and their parents were asked to complete a questionnaire. A total of 628 children were included in the prospective analysis and 964 children were included in two cross-sectional analyses at 5 years of age. Multivariable adjusted linear and logistic regression models were computed to examine prospective and cross-sectional associations between screen time and BP with adjustment for putative confounding factors. Results: No significant prospective association was found between a 2-year change in screen time and systolic BP (0.55 BP percentile change per 1 h increase in screen time, 95% confidence interval (CI) -1.51 to 2.60) and diastolic BP (0.74 BP percentile change per 1 h increase in screen time, 95% CI -1.09 to 2.57). No significant cross-sectional association was observed between screen time (⩽1 h/day, >1-2 h/day, >2 h/day) and the prevalence of high BP at 5 years of age. Exposure to screen time before bedtime 2-5 days/week and ⩾6 days/week was significantly associated with a greater prevalence of high BP compared with screen time before bedtime 0-1 day/week (odds ratios 1.57 (95% CI 1.02-2.42) and 1.82 (95% CI 1.18-2.89), respectively. Conclusions: No prospective association was found between screen time and BP. However, a significant cross-sectional association was found between screen time before bedtime and high BP in preschool children.

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.

Österreichischer Blutdruckkonsens 2019

Erhöhter Blutdruck bleibt eine Hauptursache von kardiovaskulären Erkrankungen, Behinderung und frühzeitiger Sterblichkeit in Österreich, wobei die Raten an Diagnose, Behandlung und Kontrolle auch in rezenten Studien suboptimal sind. Das Management von Bluthochdruck ist eine häufige Herausforderung für Ärztinnen und Ärzte vieler Fachrichtungen. In einem Versuch, diagnostische und therapeutische Strategien zu standardisieren und letztendlich die Rate an gut kontrollierten Hypertoniker/innen zu erhöhen und dadurch kardiovaskuläre Erkrankungen zu verhindern, haben 13 österreichische medizinische Fachgesellschaften die vorhandene Evidenz zur Prävention, Diagnose, Abklärung, Therapie und Konsequenzen erhöhten Blutdrucks gesichtet. Das hier vorgestellte Ergebnis ist der erste Österreichische Blutdruckkonsens. Die Autoren und die beteiligten Fachgesellschaften sind davon überzeugt, daß es einer gemeinsamen nationalen Anstrengung bedarf, die Blutdruck-assoziierte Morbidität und Mortalität in unserem Land zu verringern.

Impact Evaluation Using Analysis of Covariance With Error-Prone Covariates That Violate Surrogacy

BACKGROUND

Analysis of covariance (ANCOVA) is commonly used to adjust for potential confounders in observational studies of intervention effects. Measurement error in the covariates used in ANCOVA models can lead to inconsistent estimators of intervention effects. While errors-in-variables (EIV) regression can restore consistency, it requires surrogacy assumptions for the error-prone covariates that may be violated in practical settings.

OBJECTIVES

The objectives of this article are (1) to derive asymptotic results for ANCOVA using EIV regression when measurement errors may not satisfy the standard surrogacy assumptions and (2) to demonstrate how these results can be used to explore the potential bias from ANCOVA models that either ignore measurement error by using ordinary least squares (OLS) regression or use EIV regression when its required assumptions do not hold.

RESULTS

The article derives asymptotic results for ANCOVA with error-prone covariates that cover a variety of cases relevant to applications. It then uses the results in a case study of choosing among ANCOVA model specifications for estimating teacher effects using longitudinal data from a large urban school system. It finds evidence that estimates of teacher effects computed using EIV regression may have smaller bias than estimates computed using OLS regression when the data available for adjusting for students' prior achievement are limited.

Blood Pressure Change from Normal to 2017 ACC/AHA Defined Stage 1 Hypertension and Cardiovascular Risk

The purpose of this study was to investigate the clinical significance of the 2017 American College of Cardiology (ACC)/American Heart Association (AHA) defined stage 1 hypertension (systolic blood pressure (SBP) 130–139 mmHg or diastolic blood pressure (DBP) 80–89 mmHg), and increase in BP from previously normal BP in Korean adults. We conducted a retrospective analysis of 60,866 participants from a nationally representative claims database. Study subjects had normal BP (SBP < 120 mmHg and DBP < 80 mmHg), no history of anti-hypertensive medication, and cardiovascular disease (CVD) in the first period (2002–2003). The BP change was defined according to the BP difference between the first and second period (2004–2005). We used time-dependent Cox proportional hazards models in order to evaluate the effect of BP elevation on mortality and CVD with a mean follow-up of 7.8 years. Compared to those who maintained normal BP during the second period, participants with BP elevation from normal BP to stage 1 hypertension had a higher risk for CVD (adjusted hazard ratio (aHR) 1.23; 95% confidence interval (CI), 1.08–1.40), and ischemic stroke (aHR 1.32; 95% CI, 1.06–1.64). BP elevation to 2017 ACC/AHA defined elevated BP (SBP 120–129 mmHg and DBP < 80 mmHg) was associated with an increased risk of CVD (aHR 1.26; 95% CI, 1.06–1.50), but stage 1 isolated diastolic hypertension (SBP < 130 and DBP 80–89 mmHg) was not significantly related with CVD risk (aHR 1.12; 95% CI, 0.95–1.31).

Effects of magnesium citrate, magnesium oxide and magnesium sulfate supplementation on arterial stiffness in healthy overweight individuals: a study protocol for a randomized controlled trial

Background

Arterial stiffness is closely related to the process of atherosclerosis, an independent cardiovascular risk factor, and predictive of future cardiovascular events and mortality. Recently, we showed that magnesium citrate supplementation results in a clinically relevant improvement of arterial stiffness. It remained unclear whether the observed effect was due to magnesium or citrate, and whether other magnesium compounds may have similar effects. Therefore, we aim to study the long-term effects of magnesium citrate, magnesium oxide and magnesium sulfate on arterial stiffness. In addition, we aim to investigate possible underlying mechanisms, including changes in blood pressure and changes in gut microbiota diversity.

Methods

In this randomized, double-blind, placebo-controlled trial, a total of 162 healthy overweight and slightly obese men and women will be recruited. During a 24-week intervention, individuals will be randomized to receive: magnesium citrate; magnesium oxide; magnesium sulfate (total daily dose of magnesium for each active treatment 450 mg); or placebo. The primary outcome of the study is arterial stiffness measured by the carotid–femoral pulse wave velocity (PWV_c–f), which is the gold standard for quantifying arterial stiffness. Secondary outcomes are office blood pressure, measured by a continuous blood pressure monitoring device, and gut microbiota, measured in fecal samples. Measurements will be performed at baseline and at weeks 2, 12 and 24.

Discussion

The present study is expected to provide evidence for the effects of different available magnesium formulations (organic and inorganic) on well-established cardiovascular risk markers, including arterial stiffness and blood pressure, as well as on the human gut microbiota. As such, the study may contribute to the primary prevention of cardiovascular disease in slightly obese, but otherwise healthy, individuals.

Trial registration

ClinicalTrials.gov, NCT03632590. Retrospectively registered on 15 August 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3414-4) contains supplementary material, which is available to authorized users.

Wearables and the medical revolution

Wearable sensors are already impacting healthcare and medicine by enabling health monitoring outside of the clinic and prediction of health events. This paper reviews current and prospective wearable technologies and their progress toward clinical application. We describe technologies underlying common, commercially available wearable sensors and early-stage devices and outline research, when available, to support the use of these devices in healthcare. We cover applications in the following health areas: metabolic, cardiovascular and gastrointestinal monitoring; sleep, neurology, movement disorders and mental health; maternal, pre- and neo-natal care; and pulmonary health and environmental exposures. Finally, we discuss challenges associated with the adoption of wearable sensors in the current healthcare ecosystem and discuss areas for future research and development.

Understanding short-term blood-pressure-variability phenotypes: from concept to clinical practice

Clinic blood pressure (BP) is recognized as the gold standard for the screening, diagnosis, and management of hypertension. However, optimal diagnosis and successful management of hypertension cannot be achieved exclusively by a handful of conventionally acquired BP readings. It is critical to estimate the magnitude of BP variability by estimating and quantifying each individual patient's specific BP variations. Short-term BP variability or exaggerated circadian BP variations that occur within a day are associated with increased cardiovascular events, mortality and target-organ damage. Popular concepts of BP variability, including "white-coat hypertension" and "masked hypertension", are well recognized in clinical practice. However, nocturnal hypertension, morning surge, and morning hypertension are also important phenotypes of short-term BP variability that warrant attention, especially in the primary-care setting. In this review, we try to theorize and explain these phenotypes to ensure they are better understood and recognized in day-to-day clinical practice.