OPTIMA-BP: empOwering PaTients in MAnaging Blood Pressure - protocol for a randomised parallel group study comparing use of Kvatchii web-based patient education portal as an addition to home blood pressure monitoring.

INTRODUCTION: Hypertension is the leading modifiable risk factor for cardiovascular disease and is implicated in half of all strokes and myocardial infarctions. One-third of the adults in Scotland have hypertension yet only a quarter of them have their blood pressure (BP) controlled to target (<140/90 mm Hg). Empowering patients to have a better understanding of their condition and becoming actively involved in the monitoring and management of hypertension may lead to improved patient satisfaction, improved BP control and health outcomes and reduction in the use of primary/secondary care hypertension clinics. METHODS AND ANALYSIS: OPTIMA-BP is a randomised parallel group pilot study comparing the use of home BP monitoring accompanied by access to the web-based cardiovascular educational portal (Kvatchii) and home BP monitoring (HBPM) alone in 200 patients with hypertension attending the Glasgow Blood Pressure Clinic, Queen Elizabeth University Hospital, Glasgow. Consented participants will be asked to complete surveys on lifestyle factors, medication adherence, quality of life and hypertension knowledge, understanding and home monitoring. The intervention group will be asked to complete a survey to help evaluate the Kvatchii portal. At 6 and 12 months, the surveys will be repeated via the CASTOR EDC. Both groups will input their HBPM results at 2-month intervals into a CASTOR-EDC survey. OPTIMA-BP will follow-up with participants over 12 months with the study running over 24 months. The primary outcome is HBPM systolic BP area under the curve between baseline and 6 months ETHICS AND DISSEMINATION: OPTIMA-BP was approved by the North of Scotland Research Ethics Committee 2 (22/NS/0095). Current protocol version 1.2 date 6 June 2023. Written informed consent will be provided by all study participants. Study findings will be submitted to international peer-reviewed journals and will be presented at national and international scientific meetings. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov: NCT05575453. Registered 12 October 2022. https://clinicaltrials.gov/ct2/show/NCT05575453.

A Reappraisal of the Effects of L-type Ca2+ Channel Blockers on Store-Operated Ca2+ Entry and Heart Failure.

Dihydropyridines such as amlodipine are widely used as antihypertensive agents, being prescribed to ∼70 million Americans and >0.4 billion adults worldwide. Dihydropyridines block voltage-gated Ca2+ channels in resistance vessels, leading to vasodilation and a reduction in blood pressure. Various meta-analyses show that dihydropyridines are relatively safe and effective in reducing hypertension. The use of dihydropyridines has recently been called into question as these drugs appear to activate store-operated Ca2+ entry in fura-2-loaded nonexcitable cells, trigger vascular remodeling, and increase heart failure, leading to the questioning of their clinical use. Given that hypertension is the dominant "silent killer" across the globe affecting ∼1.13 billion people, removal of Ca2+ channel blockers as antihypertensive agents has major health implications. Here, we show that amlodipine has marked intrinsic fluorescence, which further increases considerably inside cells over an identical excitation spectrum as fura-2, confounding the ability to measure cytosolic Ca2+. Using longer wavelength Ca2+ indicators, we find that concentrations of Ca2+ channel blockers that match therapeutic levels in serum of patients do not activate store-operated Ca2+ entry. Antihypertensive Ca2+ channel blockers at pharmacological concentrations either have no effect on store-operated channels, activate them indirectly through store depletion or inhibit the channels. Importantly, a meta-analysis of published clinical trials and a prospective real-world analysis of patients prescribed single antihypertensive agents for 6 mo and followed up 1 yr later both show that dihydropyridines are not associated with increased heart failure or other cardiovascular disorders. Removal of dihydropyridines for treatment of hypertension cannot therefore be recommended.

Survey and Evaluation of Hypertension Machine Learning Research.

Background Machine learning (ML) is pervasive in all fields of research, from automating tasks to complex decision-making. However, applications in different specialities are variable and generally limited. Like other conditions, the number of studies employing ML in hypertension research is growing rapidly. In this study, we aimed to survey hypertension research using ML, evaluate the reporting quality, and identify barriers to ML's potential to transform hypertension care. Methods and Results The Harmonious Understanding of Machine Learning Analytics Network survey questionnaire was applied to 63 hypertension-related ML research articles published between January 2019 and September 2021. The most common research topics were blood pressure prediction (38%), hypertension (22%), cardiovascular outcomes (6%), blood pressure variability (5%), treatment response (5%), and real-time blood pressure estimation (5%). The reporting quality of the articles was variable. Only 46% of articles described the study population or derivation cohort. Most articles (81%) reported at least 1 performance measure, but only 40% presented any measures of calibration. Compliance with ethics, patient privacy, and data security regulations were mentioned in 30 (48%) of the articles. Only 14% used geographically or temporally distinct validation data sets. Algorithmic bias was not addressed in any of the articles, with only 6 of them acknowledging risk of bias. Conclusions Recent ML research on hypertension is limited to exploratory research and has significant shortcomings in reporting quality, model validation, and algorithmic bias. Our analysis identifies areas for improvement that will help pave the way for the realization of the potential of ML in hypertension and facilitate its adoption.

Underrepresentation of ethnic minorities in hypertension research-a survey of enablers and barriers among South Asian and African communities in Glasgow.

BACKGROUND: Hypertension is the biggest contributor to the global cardiovascular burden with evidence for ethnic differences in treatment response and outcomes. Under-representation of ethnic minorities in clinical research is well known, and despite wide-ranging public engagement events by the Glasgow Blood Pressure Clinic team, there was a lack of participation of ethnic minorities in both engagement activities and clinical trials conducted by them. This study aims to explore the awareness and knowledge of hypertension and the facilitators and barriers to participation in hypertension clinical research among South Asian (SA) and African (AFR) communities in Glasgow. METHODS: A survey questionnaire was co-developed with representatives from South Asian (SA) and African (AFR) patients and community members in Glasgow to understand awareness and knowledge of hypertension and enablers and barriers to participation in clinical research. The survey was distributed to adults (aged > 18) years of SA or AFR ancestry at public engagement events at venues that were frequently visited by these two communities in Glasgow. RESULTS: The survey response rate was 337 (67.4%) consisting of 242 (71.8%) South Asian (SA) and 56 (16.9%) African (AFR) respondents. Thirty-nine questionnaires were excluded because of incompletion. Most of the respondents were not born in the UK and were in the 35-53-year group (AFR 29 (51%), SA 113 (47%)). The proportion living in the most deprived (SIMD 1) and least deprived (SIMD 5) was respectively 26 (12.4%) and 34 (16.2%) for SA and 20 (42.6%) and 2 (4.3%) for AFR. There was a considerable recognition that treatment needs to be ethnicity-specific (SA/AFR = 107 (48%)/23 (45.1%)) and that current cardiovascular disease treatment guidelines were not tailored for different ethnicities 84 (38.5%)/23 (45.1%). The key enablers encouraging research participation are enhanced health information, conducting aspects of their clinical research visits/appointments at a location they frequently visited and allowing a family member to accompany them. Barriers included concerns about the use of personal information and side effects of the new treatment. CONCLUSION: Our survey confirmed enablers and barriers to ethnic minority participation in research. We find improving and evolving awareness and beliefs among the ethnic minority population including community leaders. Thus, continual review of researchers' beliefs and attitudes is also essential to ensure engagement activities keep up with these changing perceptions.

Unravelling the Distinct Effects of Systolic and Diastolic Blood Pressure Using Mendelian Randomisation.

A true discrepancy between the effect of systolic blood pressure (SBP) and diastolic blood pressure (DBP) on cardiovascular (CV) outcomes remains unclear. This study performed two-sample Mendelian randomization (MR) using genetic instruments that exclusively predict SBP, DBP or both to dissect the independent effect of SBP and DBP on a range of CV outcomes. Genetic predisposition to higher SBP and DBP was associated with increased risk of coronary artery disease (CAD), myocardial infarction (MI), stroke, heart failure (HF), atrial fibrillation (AF), chronic kidney disease (CKD) and type 2 diabetes mellitus (T2DM). Genetically proxied SBP exclusively was associated with CAD (OR 1.18, 95% CI: 1.03-1.36, per 10 mmHg), stroke (1.44[1.28-1.62]), ischemic stroke (1.49[1.30-1.69]), HF (1.41[1.20-1.65]), AF (1.28[1.15-1.43]), and T2DM (1.2[1.13-1.46]). Genetically proxied DBP exclusively was associated with stroke (1.21[1.06-1.37], per 5 mmHg), ischemic stroke (1.24[1.09-1.41]), stroke small-vessel (1.35[1.10-1.65]) and CAD (1.19[1.00-1.41]). Multivariable MR using exclusive SBP and DBP instruments showed the predominant effect of SBP on CAD (1.23[1.05-1.44], per 10 mmHg), stroke (1.39[1.20-1.60]), ischemic stroke (1.44[1.25-1.67]), HF (1.42[1.18-1.71]), AF (1.26[1.10-1.43]) and T2DM (1.31[1.14-1.52]). The discrepancy between effects of SBP and DBP on outcomes warrants further studies on underpinning mechanisms which may be amenable to therapeutic targeting.

Rationale and Design for the LOnger-term effects of SARS-CoV-2 INfection on blood Vessels And blood pRessure (LOCHINVAR): an observational phenotyping study.

INTRODUCTION: COVID-19 may lead to long-term endothelial consequences including hypertension, stroke and myocardial infarction. A pilot study 'COVID-19 blood pressure endothelium interaction study', which found that patients with normal blood pressure (BP) at the time of hospital admission with COVID-19 showed an 8.6 mm Hg higher BP ≥12 weeks after recovery, compared with a group without COVID-19. The 'LOnger-term effects of SARS-CoV-2 INfection on blood Vessels And blood pRessure'(LOCHINVAR) study is designed to provide definitive evidence of the long-term impact of COVID-19 on BP. METHODS AND ANALYSIS: The LOCHINVAR study is an observational clinical phenotyping study comparing longitudinal BP change between individuals with and without COVID-19 infection. 150 participants (30-60 years) with no history of hypertension and not on BP lowering medications will be recruited to the study to attend three visits (baseline, 12 months, 18 months). Cases will be patients who were admitted to the Queen Elizabeth University Hospital (QEUH), Glasgow, UK, with suspected/confirmed COVID-19 until 31 December 2021 and who were alive at discharge. Controls will be those who have never had confirmed COVID-19 infection. All participants will undergo clinical and vascular phenotyping studies which will include 24-hour ambulatory BP monitoring systolic BP (ABPM SBP), brachial flow-mediated dilatation urine and blood samples to assess the renin-angiotensin system, vascular inflammation and immune status. The primary outcome is the change in systolic 24-hour ABPM (ABPM SBP) between the cases and controls. Sample size was calculated to detect a mean difference of 5 mm Hg ABPM SBP at 80% power. ETHICS AND DISSEMINATION: The protocol of this study has been approved by the West of Scotland Research Ethics Committee 5 (21/WS/0075), Scotland, UK. Written informed consent will be provided by all study participants. Study findings will be submitted to international peer-reviewed hypertension journals and will be presented at international scientific meetings. TRIAL REGISTRATION NUMBER: NCT05087290.

Rationale and Design of the Genotype-Blinded Trial of Torasemide for the Treatment of Hypertension (BHF UMOD).

BACKGROUND: Genome-wide association studies have identified single nucleotide polymorphisms (SNPs) near the uromodulin gene (UMOD) affecting uromodulin excretion and blood pressure (BP). Uromodulin is almost exclusively expressed in the thick ascending limb (TAL) of the loop of Henle and its effect on BP appears to be mediated via the TAL sodium transporter, NKCC2. Loop-diuretics block NKCC2 but are not commonly used in hypertension management. Volume overload is one of the primary drivers for uncontrolled hypertension, so targeting loop-diuretics to individuals who are more likely to respond to this drug class, using the UMOD genotype, could be an efficient precision medicine strategy. METHODS: The BHF UMOD Trial is a genotype-blinded, multicenter trial comparing BP response to torasemide between individuals possessing the AA genotype of the SNP rs13333226 and those possessing the G allele. 240 participants (≥18 years) with uncontrolled BP, on ≥1 antihypertensive agent for ≥3 months, will receive treatment with Torasemide, 5 mg daily for 16 weeks. Uncontrolled BP is average home systolic BP (SBP) >135 mmHg and/or diastolic BP >85 mmHg. The primary outcome is the change in 24-hour ambulatory SBP area under the curve between baseline and end of treatment. Sample size was calculated to detect a 4 mmHg difference between groups at 90% power. Approval by West of Scotland Research Ethics Committee 5 (16/WS/0160). RESULTS: The study should conclude August 2021. CONCLUSIONS: If our hypothesis is confirmed, a genotype-based treatment strategy for loop diuretics would help reduce the burden of uncontrolled hypertension. CLINICAL TRIALS REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT03354897.

Genomics of Blood Pressure and Hypertension: Extending the Mosaic Theory Toward Stratification.

The genetic architecture of blood pressure (BP) now includes more than 30 genes, with rare mutations resulting in inherited forms of hypertension or hypotension, and 1477 common single-nucleotide polymorphisms (SNPs). These signify the heterogeneity of the BP phenotype and support the mosaic theory of hypertension. The majority of monogenic syndromes involve the renin-angiotensin-aldosterone system and the adrenal glucocorticoid pathway, and a smaller fraction are due to rare neuroendocrine tumours of the adrenal glands and the sympathetic and parasympathetic paraganglia. Somatic mutations in genes coding for ion channels (KCNJ5 and CACNA1D) and adenosine triphosphatases (ATP1A1 and ATP2B3) highlight the central role of calcium signalling in autonomous aldosterone production by the adrenal gland. The per-SNP BP effect is small for SNPs according to genome-wide association studies (GWAS), and all of the GWAS-identified BP SNPs explain ∼ 27% of the 30%-50% estimated heritability of BP. Uromodulin is a novel pathway identified by GWAS, and it has now progressed to a genotype-directed clinical trial. The majority of the GWAS-identified BP SNPs show pleiotropic associations, and unravelling those signals and underpinning biological pathways offers potential opportunities for drug repurposing. The GWAS signals are predominantly from Europe-centric studies with other ancestries underrepresented, however, limiting the generalisability of the findings. In this review, we leverage the burgeoning list of polygenic and monogenic variants associated with BP regulation along with phenome-wide studies in the context of the mosaic theory of hypertension, and we explore potential translational aspects that underlie different hypertension subtypes.

Diastolic Blood Pressure J-Curve Phenomenon in a Tertiary-Care Hypertension Clinic.

Concerns exist regarding the potential increased cardiovascular risk from lowering diastolic blood pressure (DBP) in hypertensive patients. We analyzed 30-year follow-up data of 10 355 hypertensive patients attending the Glasgow Blood Pressure Clinic. The association between blood pressure during the first 5 years of treatment and cause-specific hospital admissions or mortality was analyzed using multivariable adjusted Cox proportional hazard models. The primary outcome was a composite of cardiovascular admissions and deaths. DBP showed a U-shaped association (nadir, 92 mm Hg) for the primary cardiovascular outcome hazard and a reverse J-shaped association with all-cause mortality (nadir, 86 mm Hg) and noncardiovascular mortality (nadir, 92 mm Hg). The hazard ratio for the primary cardiovascular outcome after adjustment for systolic blood pressure was 1.38 (95% CI, 1.18-1.62) for DBP <80 compared with DBP of 80 to 89.9 mm Hg (referrant), and the subdistribution hazard ratio after accounting for competing risk was 1.33 (1.17-1.51) compared with DBP ≥80 mm Hg. Cause-specific nonfatal outcome analyses showed a reverse J-shaped relationship for myocardial infarction, ischemic heart disease, and heart failure admissions but a U-shaped relationship for stroke admissions. Age-stratified analyses showed DBP had no independent effect on stroke admissions among the older patient subgroup (≥60 years of age), but the younger subgroup showed a clear U-shaped relationship. Intensive blood pressure reduction may lead to unintended consequences of higher healthcare utilization because of increased cardiovascular morbidity, and this merits future prospective studies. Low on-treatment DBP is associated with increased risk of noncardiovascular mortality, the reasons for which are unclear.

Prevalence of under and over weight in children with neurodisability, using body composition measures.

We aimed to compare rates of under and overweight in children with different neurodevelopmental disorders (NDD) by measuring weight, height/length, arm-to-leg bioelectrical impedance (BIA) and subscapular and triceps skinfolds in 146 children aged 4-16 years attending special schools. Z scores were calculated and skinfolds and lean mass Z scores were further adjusted for height. Underweight was found in 9% (14) children (body mass index (BMI) < 2nd) but only 3% (4) had skinfolds <5th centile. Overweight was much commoner, with 41% (58) children having BMI > 95th and 20% (14) had skinfolds >95th centile. Children with cerebral palsy were very short with low BMI and lean mass, but only 8% (3) had skinfolds <5th centile. The children with Down syndrome were also very short and once adjusted for height, half had skinfolds >95th centile. We conclude that overweight and raised body fat is now common in children with NDD, even when the BMI is low.

Does measurement technique explain the mismatch between European head size and WHO charts?

OBJECTIVE: To test whether different measuring techniques produce systematic differences in head size that could explain the large head circumferences found in Northern European children compared with the WHO standard. DESIGN: Cross-sectional observational study. SETTING: Scotland, UK. PATIENTS: Study 1: 68 healthy children aged 0.4-18 months from mother and baby groups and a medical students teaching session. Study 2: 81 children aged 0.4 to 25 months from hospital wards and neonatal follow-up clinics. INTERVENTIONS: Study 1: heads measured with plastic tape using both the WHO tight and UK loose technique. Study 2: heads measured using WHO research technique and a metal measuring tape and compared with routinely acquired measurements. MAIN OUTCOME MEASURES: Mean difference in head z-scores using WHO standard between the two methods. RESULTS: The tight technique resulted in a mean (95% CI) z-score difference of 0.41 (0.27 to 0.54, p<0.001) in study 1 and 0.44 (0.36 to 0.53, p<0.001) in study 2. However, the mean WHO measurements in the healthy infants still produced a mean z-score that was two-third of a centile space (0.54 SD (0.28 to 0.79) p<0.001) above the 50th centile. CONCLUSION: The WHO measurement techniques produced significantly lower measures of head size, but average healthy Scottish children still had larger heads than the WHO standard using this method.

Contrasting mortality risks among subgroups of treated hypertensive patients developing new-onset diabetes.

AIMS: Hypertension and diabetes mellitus (DM) frequently cluster together and synergistically increase cardiovascular risk. Among those who develop DM during treatment for hypertension (new-onset diabetes, NOD), it is unclear whether NOD reflects a separate entity associated with increased risk or merely reflects accelerated presentation of DM. METHODS AND RESULTS: We analysed data on 15 089 hypertensive patients attending the Glasgow Blood Pressure Clinic. The date at first hospital encounter either with diagnosis of diabetes or prescription of anti-hyperglycaemic medication were considered as the onset of diabetes. Cox proportional hazard models (including propensity score matching) were employed to study associations between diabetes status, early and late NOD (diagnosis <10 years or >10 years from first clinic visit) and cause-specific mortality. There were 2516 patients (16.7%) with DM, of whom 1862 (12.3%) had NOD [early NOD = 705 (4.6%); late NOD = 1157 (7.6%)]. The incidence rate of NOD was 8.2 per 1000 person-years. The total time at risk was 239 929 person-years [median survival: 28.1 years (inter-quartile range: 16.2-39.9)]. Compared with non-diabetic individuals, prevalent DM [hazard ratio (HR) = 1.8, 95% confidence interval (CI): 1.4-2.2] and time varying NOD status (HR: 1.09, 95% CI: 1.06-1.17) were associated with increased adjusted all-cause mortality. Early NOD (HR: 1.39, 95% CI: 1.2-1.6) was associated with increased in mortality risk, but not late NOD (HR: 0.92, 95% CI: 0.83-1.01). Results were consistent in the propensity score matched analyses. CONCLUSION: Although 1-in-8 hypertensive patients develop NOD, mortality is increased only in the 1-in-20 who develop early NOD. Further studies are warranted to determine if early identification of such individuals should provide an alert for intensification of therapeutic interventions.

The hidden hand of chloride in hypertension.

Among the environmental factors that affect blood pressure, dietary sodium chloride has been studied the most, and there is general consensus that increased sodium chloride intake increases blood pressure. There is accruing evidence that chloride may have a role in blood pressure regulation which may perhaps be even more important than that of Na(+). Though more than 85 % of Na(+) is consumed as sodium chloride, there is evidence that Na(+) and Cl(-) concentrations do not go necessarily hand in hand since they may originate from different sources. Hence, elucidating the role of Cl(-) as an independent player in blood pressure regulation will have clinical and public health implications in addition to advancing our understanding of electrolyte-mediated blood pressure regulation. In this review, we describe the evidence that support an independent role for Cl(-) on hypertension and cardiovascular health.

A meta-analysis of the risk of boys with isolated cryptorchidism developing testicular cancer in later life.

BACKGROUND: Significant variability exists for the relative risk (RR) of testicular malignancy in isolated cryptorchidism. OBJECTIVE: To perform a meta-analysis to clarify the true magnitude of this risk, allowing clinicians to better counsel patients and their families. SETTING: Secondary research conducted by undergraduate researchers, clinical academics and a clinical statistician. DESIGN, DATA SOURCES, AND METHODS: A search of the English literature was performed for studies relating to testicular cancer and cryptorchidism, published between 1 January 1980 and 31 December 2010, using Embase and Medline databases. 735 papers were identified and analysed by four authors independently in accordance with our inclusion and exclusion criteria. Studies reporting an association between cryptorchidism and subsequent development of testicular malignancy were included. Genetic syndromes or other conditions which predisposed to the development of cryptorchidism were excluded. Pooled estimates and 95% CIs for the RRs were calculated. RESULTS: Nine case-control studies and three cohort studies were selected. The case-control studies included 2281 cases and 4811 controls. Cohort studies included 2 177 941 boys, with a total of 345 boys developing testicular cancer (total length of follow-up was 58 270 679 person-years). The pooled RR was 2.90 (95% CI 2.21 to 3.82) with significant heterogeneity (p<0.00001; I(2)=89%). CONCLUSION: Boys with isolated cryptorchidism are three times more likely to develop testicular cancer. The limitations of this study must be acknowledged, in particular, possible publication bias and the lack of high-quality evidence focusing on the risk of malignancy in boys with isolated cryptorchidism.