Accuracy of monitors used for blood pressure checks in English retail pharmacies::a cross-sectional observational study

BACKGROUND: Free blood pressure (BP) checks offered by community pharmacies provide a potentially useful opportunity to diagnose and/or manage hypertension, but the accuracy of the sphygmomanometers in use is currently unknown. AIM: To assess the accuracy of validated automatic BP monitors used for BP checks in a UK retail pharmacy chain. DESIGN AND SETTING: Cross-sectional, observational study in 52 pharmacies from one chain in a range of locations (inner city, suburban, and rural) in central England. METHOD: Monitor accuracy was compared with a calibrated reference device (Omron PA-350), at 50 mmHg intervals across the range 0–300 mmHg (static pressure test), with a difference from the reference monitor of +/− 3 mmHg at any interval considered a failure. The results were analysed by usage rates and length of time in service. RESULTS: Of 61 BP monitors tested, eight (13%) monitors failed (that is, were >3 mmHg from reference), all of which underestimated BP. Monitor failure rate from the reference monitor of +/− 3 mmHg at any testing interval varied by length of time in use (2/38, 5% <18 months; 4/14, 29% >18 months, P = 0.038) and to some extent, but non-significantly, by usage rates (4/22, 18% in monitors used more than once daily; 2/33, 6% in those used less frequently, P = 0.204). CONCLUSION: BP monitors within a pharmacy setting fail at similar rates to those in general practice. Annual calibration checks for blood pressure monitors are needed, even for new monitors, as these data indicate declining performance from 18 months onwards

Protocol for Past BP: a randomised controlled trial of different blood pressure targets for people with a history of stroke of transient ischaemic attack (TIA) in primary care.

BACKGROUND: Blood pressure (BP) lowering in people who have had a stroke or transient ischaemic attack (TIA) leads to reduced risk of further stroke. However, it is not clear what the target BP should be, since intensification of therapy may lead to additional adverse effects. PAST BP will determine whether more intensive BP targets can be achieved in a primary care setting, and whether more intensive therapy is associated with adverse effects on quality of life. METHODS/DESIGN: This is a randomised controlled trial (RCT) in patients with a past history of stroke or TIA. Patients will be randomised to two groups and will either have their blood pressure (BP) lowered intensively to a target of 130 mmHg systolic, (or by 10 mmHg if the baseline systolic pressure is between 125 and 140 mmHg) compared to a standard group where the BP will be reduced to a target of 140 mmHg systolic. Patients will be managed by their practice at 1-3 month intervals depending on level of BP and followed-up by the research team at six monthly intervals for 12 months.610 patients will be recruited from approximately 50 general practices. The following exclusion criteria will be applied: systolic BP <125 mmHg at baseline, 3 or more anti-hypertensive agents, orthostatic hypotension, diabetes mellitus with microalbuminuria or other condition requiring a lower treatment target or terminal illness.The primary outcome will be change in systolic BP over twelve months. Secondary outcomes include quality of life, adverse events and cardiovascular events.In-depth interviews with 30 patients and 20 health care practitioners will be undertaken to investigate patient and healthcare professionals understanding and views of BP management. DISCUSSION: The results of this trial will inform whether intensive blood pressure targets can be achieved in people who have had a stroke or TIA in primary care, and help determine whether or not further research is required before recommending such targets for this population. TRIAL REGISTRATION: ISRCTN29062286.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

The REFER (REFer for EchocaRdiogram) protocol: a prospective validation of a clinical decision rule, NT-proBNP, or their combination, in the diagnosis of heart failure in primary care. Rationale and design.

BACKGROUND: Heart failure is a major cause of mortality and morbidity. As mortality rates are high, it is important that patients seen by general practitioners with symptoms suggestive of heart failure are identified quickly and treated appropriately. Identifying patients with heart failure or deciding which patients need further tests is a challenge. All patients with suspected heart failure should be diagnosed using objective tests such as echocardiography, but it is expensive, often delayed, and limited by the significant skill shortage of trained echocardiographers. Alternative approaches for diagnosing heart failure are currently limited. Clinical decision tools that combine clinical signs, symptoms or patient characteristics are designed to be used to support clinical decision-making and validated according to strict methodological procedures. The REFER Study aims to determine the accuracy and cost-effectiveness of our previously derived novel, simple clinical decision rule, a natriuretic peptide assay, or their combination, in the triage for referral for echocardiography of symptomatic adult patients who present in general practice with symptoms suggestive of heart failure. METHODS/DESIGN: This is a prospective, Phase II observational, diagnostic validation study of a clinical decision rule, natriuretic peptides or their combination, for diagnosing heart failure in primary care. Consecutive adult primary care patients 55 years of age or over presenting to their general practitioner with a chief complaint of recent new onset shortness of breath, lethargy or peripheral ankle oedema of over 48 hours duration, with no obvious recurrent, acute or self-limiting cause will be enrolled. Our reference standard is based upon a three step expert specialist consensus using echocardiography and clinical variables and tests. DISCUSSION: Our clinical decision rule offers a potential solution to the diagnostic challenge of providing a timely and accurate diagnosis of heart failure in primary care. Study results will provide an evidence-base from which to develop heart failure care pathway recommendations and may be useful in standardising care. If demonstrated to be effective, the clinical decision rule will be of interest to researchers, policy makers and general practitioners worldwide. TRIAL REGISTRATION: ISRCTN17635379.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Self-monitoring blood pressure in patients with hypertension: an internet-based survey of UK GPs.

BACKGROUND: Previous research suggests that most GPs in the UK use self-monitoring of blood pressure (SMBP) to monitor the control of hypertension rather than for diagnosis. This study sought to assess current practice in the use of self-monitoring and any changes in practice following more recent guideline recommendations. AIM: To survey the views and practice of UK GPs in 2015 with regard to SMBP and compare them with a previous survey carried out in 2011. DESIGN AND SETTING: Web-based survey of a regionally representative sample of 300 UK GPs. METHOD: GPs completed an online questionnaire concerning the use of SMBP in the management of hypertension. Analyses comprised descriptive statistics, tests for between-group differences (z, Wilcoxon signed-rank, and χ2 tests), and multivariate logistic regression. RESULTS: Results were available for 300 GPs (94% of those who started the survey). GPs reported using self-monitoring to diagnose hypertension (169/291; 58%; 95% confidence interval (CI) = 52 to 64) and to monitor control (245/291; 84%; 95% CI = 80 to 88), the former having significantly increased since 2011 (from 37%; 95% CI = 33 to 41; P<0.001) with no change in monitoring for control. More than half of GPs used higher systolic thresholds for diagnosis (118/169; 70%; 95% CI = 63 to 77) and treatment (168/225; 75%; 95% CI = 69 to 80) than recommended in guidelines, and under half (120/289; 42%; 95% CI = 36 to 47) adjusted the SMBP results to guide treatment decisions. CONCLUSION: Since new UK national guidance in 2011, GPs are more likely to use SMBP to diagnose hypertension. However, significant proportions of GPs continue to use non-standard diagnostic and monitoring thresholds. The use of out-of-office methods to improve the accuracy of diagnosis is unlikely to be beneficial if suboptimal thresholds are used.This study was funded by the British Hypertension Society and the NIHR. Ben Fletcher receives funding from the National Institute for Health Research (NIHR) School for Primary Care Research (SPCR) Doctoral Studentship. Richard McManus holds an NIHR Professorship (RP-02-12-015)) and receives funding from the NIHR Oxford CLAHRC. This article presents independent research funded by the NIHR. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health.This is the author accepted manuscript. The final version is available from Royal College of General Practitioners via https://doi.org/10.3399/bjgp16X68703

Different systolic blood pressure targets for people with history of stroke or transient ischaemic attack: PAST-BP (Prevention After Stroke--Blood Pressure) randomised controlled trial.

OBJECTIVE: To assess whether using intensive blood pressure targets leads to lower blood pressure in a community population of people with prevalent cerebrovascular disease. DESIGN: Open label randomised controlled trial. SETTING: 99 general practices in England, with participants recruited in 2009-11. PARTICIPANTS: People with a history of stroke or transient ischaemic attack whose systolic blood pressure was 125 mm Hg or above. INTERVENTIONS: Intensive systolic blood pressure target (<130 mm Hg or 10 mm Hg reduction from baseline if this was <140 mm Hg) or standard target (<140 mm Hg). Apart from the different target, patients in both arms were actively managed in the same way with regular reviews by the primary care team. MAIN OUTCOME MEASURE: Change in systolic blood pressure between baseline and 12 months. RESULTS: 529 patients (mean age 72) were enrolled, 266 to the intensive target arm and 263 to the standard target arm, of whom 379 were included in the primary analysis (182 (68%) intensive arm; 197 (75%) standard arm). 84 patients withdrew from the study during the follow-up period (52 intensive arm; 32 standard arm). Mean systolic blood pressure dropped by 16.1 mm Hg to 127.4 mm Hg in the intensive target arm and by 12.8 mm Hg to 129.4 mm Hg in the standard arm (difference between groups 2.9 (95% confidence interval 0.2 to 5.7) mm Hg; P=0.03). CONCLUSIONS: Aiming for target below 130 mm Hg rather than 140 mm Hg for systolic blood pressure in people with cerebrovascular disease in primary care led to a small additional reduction in blood pressure. Active management of systolic blood pressure in this population using a <140 mm Hg target led to a clinically important reduction in blood pressure.Trial registration Current Controlled Trials ISRCTN29062286.This report is independent research funded by the National Institute for Health Research (Stroke Prevention in Primary Care, Programme Grant for Applied Research, RP-PG-0606-1153), and by an NIHR Professorship (Prof McManus). FDRH is part funded as Director of the National Institute for Health Research (NIHR) School for Primary Care Research (SPCR), Theme Leader of the NIHR Oxford Biomedical Research Centre (BRC), and Director of the NIHR Collaboration for Leadership in Applied Health Research and Care (CLAHRC) Oxford. The views expressed in this publication are those of the author(s) and not necessarily those of the NHS. The study sponsor was the University of Birmingham. The study funder and sponsor had no role in the study design, collection, analysis or interpretation of data, in the writing of the report, or in the decision to submit to publication. The researchers are independent of the funders.This is the final version of the article. It first appeared from the BMJ Publishing Group via http://dx.doi.org/10.1136/bmj.i70

Predicting out-of-office blood pressure level using repeated measurements in the clinic: an observational cohort study.

OBJECTIVES: Identification of people with lower (white-coat effect) or higher (masked effect) blood pressure at home compared to the clinic usually requires ambulatory or home monitoring. This study assessed whether changes in SBP with repeated measurement at a single clinic predict subsequent differences between clinic and home measurements. METHODS: This study used an observational cohort design and included 220 individuals aged 35-84 years, receiving treatment for hypertension, but whose SBP was not controlled. The characteristics of change in SBP over six clinic readings were defined as the SBP drop, the slope and the quadratic coefficient using polynomial regression modelling. The predictive abilities of these characteristics for lower or higher home SBP readings were investigated with logistic regression and repeated operating characteristic analysis. RESULTS: The single clinic SBP drop was predictive of the white-coat effect with a sensitivity of 90%, specificity of 50%, positive predictive value of 56% and negative predictive value of 88%. Predictive values for the masked effect and those of the slope and quadratic coefficient were slightly lower, but when the slope and quadratic variables were combined, the sensitivity, specificity, positive and negative predictive values for the masked effect were improved to 91, 48, 24 and 97%, respectively. CONCLUSION: Characteristics obtainable from multiple SBP measurements in a single clinic in patients with treated hypertension appear to reasonably predict those unlikely to have a large white-coat or masked effect, potentially allowing better targeting of out-of-office monitoring in routine clinical practice.This study presents independent research commissioned by the National Institute for Health Research (NIHR) under its Programme Grants for Applied Research funding scheme (RP-PG-1209–10051). R.J.Mc.M. holds an NIHR Professorship. J.S. was funded by the NIHR Birmingham and Black Country Collaboration for Leadership in Applied Health Research and Care during part of this work, but now holds a Medical Research Council Strategic Skills Postdoctoral Fellowship. B.W. is a NIHR Senior Investigator and is supported by the NIHR UCL Hospitals Biomedical Research Centre. The TASMINH2 trial was funded by the UK Department of Health Policy Research Programme and the National Coordinating Centre for Research Capacity Development. The views and opinions expressed are those of the authors and do not necessarily reflect those of the NHS, NIHR, or the Department of Health. All equipment used in the study was purchased commercially

Protocol for a randomised controlled trial of telemonitoring and self-management in the control of hypertension: telemonitoring and self-management in hypertension. [ISRCTN17585681].

BACKGROUND: Controlling blood pressure with drugs is a key aspect of cardiovascular disease prevention, but until recently has been the sole preserve of health professionals. Self-management of hypertension is an under researched area in which potential benefits for both patients and professionals are great. METHODS AND DESIGN: The telemonitoring and self-management in hypertension trial (TASMINH2) will be a primary care based randomised controlled trial with embedded economic and qualitative analyses in order to evaluate the costs and effects of increasing patient involvement in blood pressure management, specifically with respect to home monitoring and self titration of antihypertensive medication compared to usual care. Provision of remote monitoring results to participating practices will ensure that practice staff are able to engage with self management and provide assistance where required. 478 patients will be recruited from general practices in the West Midlands, which is sufficient to detect clinically significant differences in systolic blood pressure between self-management and usual care of 5 mmHg with 90% power. Patients will be excluded if they demonstrate an inability to self monitor, their blood pressure is below 140/90 or above 200/100, they are on three or more antihypertensive medications, have a terminal disease or their blood pressure is not managed by their general practitioner. The primary end point is change in mean systolic blood pressure (mmHg) between baseline and each follow up point (6 months and 12 months). Secondary outcomes will include change in mean diastolic blood pressure, costs, adverse events, health behaviours, illness perceptions, beliefs about medication, medication compliance and anxiety. Modelling will evaluate the impact of costs and effects on a system wide basis. The qualitative analysis will draw upon the views of users, informal carers and professionals regarding the acceptability of self-management and prerequisites for future widespread implementation should the trial show this approach to be efficacious. DISCUSSION: The TASMINH2 trial will provide important new evidence regarding the costs and effects of self monitoring with telemonitoring in a representative primary care hypertensive population.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Cost-effectiveness analysis of different systolic blood pressure targets for people with a history of stroke or transient ischaemic attack: Economic analysis of the PAST-BP study.

BACKGROUND: The PAST-BP trial found that using a lower systolic blood pressure target (<130 mmHg or lower versus <140 mmHg) in a primary care population with prevalent cerebrovascular disease was associated with a small additional reduction in blood pressure (2.9 mmHg). OBJECTIVES: To determine the cost effectiveness of an intensive systolic blood pressure target (<130 mmHg or lower) compared with a standard target (<140 mmHg) in people with a history of stroke or transient ischaemic attack on general practice stroke/transient ischaemic attack registers in England. METHODS: A Markov model with a one-year time cycle and a 30-year time horizon was used to estimate the cost per quality-adjusted life year of an intensive target versus a standard target. Individual patient level data were used from the PAST-BP trial with regard to change in blood pressure and numbers of primary care consultations over a 12-month period. Published sources were used to estimate life expectancy and risks of cardiovascular events and their associated costs and utilities. RESULTS: In the base-case results, aiming for an intensive blood pressure target was dominant, with the incremental lifetime costs being £169 lower per patient than for the standard blood pressure target with a 0.08 quality-adjusted life year gain. This was robust to sensitivity analyses, unless intensive blood pressure lowering reduced quality of life by 2% or more. CONCLUSION: Aiming for a systolic blood pressure target of <130 mmHg or lower is cost effective in people who have had a stroke/transient ischaemic attack in the community, but it is difficult to separate out the impact of the lower target from the impact of more active management of blood pressure.National Institute for Health Research (Grant ID: RP-PG-0606-1153)This is the author accepted manuscript. The final version is available from SAGE Publications via http://dx.doi.org/10.1177/204748731665198

Accuracy of blood pressure monitors owned by patients with hypertension (ACCU-RATE study)

Background Home blood pressure (BP) monitoring is recommended in guidelines and increasingly popular with patients and health care professionals, but the accuracy of patients’ own monitors in real world use is not known. Aim To assess the accuracy of home BP monitors used by people with hypertension, and investigate factors affecting accuracy. Design and Setting Patients on the hypertension register at seven practices in central England were surveyed to ascertain if they owned a monitor and wanted it tested. Method Monitor accuracy was compared to a calibrated reference device, at 50 mmHg intervals between 0-280/300 mmHg (static pressure test), with a difference from the reference monitor of +/-3 mmHg at any interval considered a failure. Cuff performance was also assessed. Results were analysed by usage rates, length of time in service, make and model, monitor validation status, cost, and any previous testing. Results 251 (76%, 95% CI 71-80%) of 331 tested devices passed all tests (monitors and cuffs) and 86% passed the static pressure test, deficiencies primarily due to overestimation. 40% of testable monitors were unvalidated. Pass rate on the static pressure test was greater in validated monitors (96% [95% CI 94-98%] vs 64% [95% CI 58-69%]), those retailing for over £10, and those in use for less than four years.12% of cuffs failed. Conclusion Patients’ own BP monitor failure rate was similar to that in studies performed in professional settings, though cuff failure was more frequent. Clinicians can be confident of the accuracy of patients’ own BP monitors, if validated and less than five years old.This work represents independent research commissioned by the National Institute for Health Research (NIHR) under its Programme Grants for Applied Research funding scheme (RP-PG-1209-10051). The views expressed in this study are those of the authors and not necessarily of the NHS, the NIHR or the Department of Health. RJM was supported by an NIHR Professorship (NIHR-RP-02-12-015) and by the NIHR Collaboration for Leadership in Applied Health Research and Care (CLAHRC) Oxford at Oxford Health NHS Foundation Trust. FDRH is part funded as Director of the National Institute for Health Research (NIHR) School for Primary Care Research (SPCR), Theme Leader of the NIHR Oxford Biomedical Research Centre (BRC), and Director of the NIHR CLAHRC Oxford. JM is an NIHR Senior Investigator. No funding for this study was received from any monitor manufacturer

Accuracy of blood-pressure monitors owned by patients with hypertension (ACCU-RATE study): a cross-sectional, observational study in central England.

BACKGROUND: Home blood-pressure (BP) monitoring is recommended in guidelines and is increasingly popular with patients and health professionals, but the accuracy of patients' own monitors in real-world use is not known. AIM: To assess the accuracy of home BP monitors used by people with hypertension, and to investigate factors affecting accuracy. DESIGN AND SETTING: Cross-sectional, observational study in urban and suburban settings in central England. METHOD: Patients (n = 6891) on the hypertension register at seven practices in the West Midlands, England, were surveyed to ascertain whether they owned a BP monitor and wanted it tested. Monitor accuracy was compared with a calibrated reference device at 50 mmHg intervals between 0-280/300 mmHg (static pressure test); a difference from the reference monitor of +/-3 mmHg at any interval was considered a failure. Cuff performance was also assessed. Results were analysed by frequency of use, length of time in service, make and model, monitor validation status, purchase price, and any previous testing. RESULTS: In total, 251 (76%, 95% confidence interval [95% CI] = 71 to 80%) of 331 tested devices passed all tests (monitors and cuffs), and 86% (CI] = 82 to 90%) passed the static pressure test; deficiencies were, primarily, because of monitors overestimating BP. A total of 40% of testable monitors were not validated. The pass rate on the static pressure test was greater in validated monitors (96%, 95% CI = 94 to 98%) versus unvalidated monitors (64%, 95% CI = 58 to 69%), those retailing for >£10 (90%, 95% CI = 86 to 94%), those retailing for ≤£10 (66%, 95% CI = 51 to 80%), those in use for ≤4 years (95%, 95% CI = 91 to 98%), and those in use for >4 years (74%, 95% CI = 67 to 82%). All in all, 12% of cuffs failed. CONCLUSION: Patients' own BP monitor failure rate was similar to that demonstrated in studies performed in professional settings, although cuff failure was more frequent. Clinicians can be confident of the accuracy of patients' own BP monitors if the devices are validated and ≤4 years old