Publications by year
In Press
Clark C, Albsri A, Omboni S, McDonagh S, Fletcher B, McManus R, Shappard J (In Press). Hypertension: evidence for effective detection and management through pharmacy.
The Pharmaceutical journal Full text.
McDonagh S, Clark CE (In Press). Inter-arm differences in blood pressure: a brief summary.
Diabetes and Primary Care,
21 Full text.
McDonagh STJ, Mejzner N, Clark CE (In Press). Prevalence of Postural Hypotension in Primary, Community and Institutional Care: a Systematic Review and Meta-Analysis.
Abstract:
Prevalence of Postural Hypotension in Primary, Community and Institutional Care: a Systematic Review and Meta-Analysis
Abstract
. Background: Postural hypotension (PH), the reduction in blood pressure when rising from sitting or lying to standing, is a risk factor for falls, cognitive decline and mortality. However, it is not often tested for in primary care despite these associated risks. PH prevalence varies according to definition, population, care setting and measurement method. The aim of this study was to determine the prevalence of PH across different care settings and disease subgroups.Methods: a systematic review, meta-analyses and meta-regression were undertaken. We searched Medline and Embase to October 2019 for studies based in primary, community or institutional care settings reporting PH prevalence. Data and study level demographics were extracted independently by two reviewers. Pooled estimates for mean prevalence of PH were compared between care settings and disease subgroups using random effects meta-analyses. Predictors of PH were explored using meta-regression. Quality assessment of included studies was undertaken using an adapted version of the Newcastle-Ottawa Scale.Results: 1816 studies were identified; 61 contributed to analyses. Pooled prevalences for PH using the consensus definition were 17% (95% CI, 14-20%) in the community, 19% (15-25%) in primary care and 31% (15-50%) in residential care or nursing homes (P=0.16 between groups). By condition, prevalences were 20% (16-24%) with hypertension, 21% (16-26%) with diabetes, 25% (18-33%) with Parkinson’s disease and 29% (25-33%) with dementia, compared to 14% (12-17%) without these conditions (P<0.01 between groups). Multivariable meta-regression modelling identified increasing age and diabetes as predictors of PH (P<0.01, P=0.13, respectively; R2=36%). PH prevalence was not affected by blood pressure measurement device (P=0.65) or sitting or supine resting position (P=0.24), however, when the definition of PH did not fulfil the consensus description, but fell within its parameters, prevalence was underestimated (P=0.01) irrespective of study quality (P=0.04).Conclusions: the prevalence of PH in populations relevant to primary care is substantial. The definition used is important when testing for PH. Our findings emphasise the importance of considering checking for PH, particularly in vulnerable populations, to enable interventions to manage it. These data should contribute to future guidelines relevant to the detection and treatment of postural hypotension.PROSPERO: CRD42017075423.
Abstract.
Clark C, Thomas D, Llewellyn D, Ferrucci L, Bandinelli S, Campbell J (In Press). Systolic inter-arm blood pressure difference and risk of cognitive decline in the elderly: cohort study.
British Journal of General Practice Full text.
Norris M, Poltawski L, Calitri RA, Shepherd A, Dean S (In Press). The acceptability and experience of a functional training programme (ReTrain) in community dwelling stroke survivors in South West England: a qualitative study.
BMJ Open Full text.
2021
Gomez-Cano M, Wiering B, Abel G, Campbell JL, Clark CE (2021). Medication adherence and clinical outcomes in dispensing and non-dispensing practices: a cross-sectional analysis.
Br J Gen Pract,
71(702), e55-e61.
Abstract:
Medication adherence and clinical outcomes in dispensing and non-dispensing practices: a cross-sectional analysis.
BACKGROUND: Most patients obtain medications from pharmacies by prescription, but rural general practices can dispense medications. The clinical implications of this difference in drug delivery are unknown. This study hypothesised that dispensing status may be associated with better medication adherence. This could impact intermediate clinical outcomes dependent on medication adherence in, for example, hypertension or diabetes. AIM: to investigate whether dispensing status is associated with differences in achievement of Quality and Outcomes Framework (QOF) indicators that rely on medication adherence. DESIGN AND SETTING: Cross-sectional analysis of QOF data for 7392 general practices in England. METHOD: QOF data from 1 April 2016 to 31 March 2017 linked to dispensing status for general practices with list sizes ≥1000 in England were analysed. QOF indicators were categorised according to whether their achievement depended on a record of prescribing only, medication adherence, or neither. Differences were estimated between dispensing and non-dispensing practices using mixed-effects logistic regression, adjusting for practice population age, sex, deprivation, list size, single-handed status, and rurality. RESULTS: Data existed for 7392 practices; 1014 (13.7%) could dispense. Achievement was better in dispensing practices than in non-dispensing practices for seven of nine QOF indicators dependent on adherence, including blood pressure targets. Only one of ten indicators dependent on prescribing but not adherence displayed better achievement; indicators unrelated to prescribing showed a trend towards higher achievement by dispensing practices. CONCLUSION: Dispensing practices may achieve better clinical outcomes than prescribing practices. Further work is required to explore underlying mechanisms for these observations and to directly study medication adherence rates.
Abstract.
Author URL.
Full text.
McDonagh STJ, Mejzner N, Clark CE (2021). Prevalence of postural hypotension in primary, community and institutional care: a systematic review and meta-analysis.
BMC Family Practice,
22(1).
Abstract:
Prevalence of postural hypotension in primary, community and institutional care: a systematic review and meta-analysis
Abstract
. Background
. Postural hypotension (PH), the reduction in blood pressure when rising from sitting or lying 0to standing, is a risk factor for falls, cognitive decline and mortality. However, it is not often tested for in primary care. PH prevalence varies according to definition, population, care setting and measurement method. The aim of this study was to determine the prevalence of PH across different care settings and disease subgroups.
.
. Methods
. Systematic review, meta-analyses and meta-regression. We searched Medline and Embase to October 2019 for studies based in primary, community or institutional care settings reporting PH prevalence. Data and study level demographics were extracted independently by two reviewers. Pooled estimates for mean PH prevalence were compared between care settings and disease subgroups using random effects meta-analyses. Predictors of PH were explored using meta-regression. Quality assessment was undertaken using an adapted Newcastle-Ottawa Scale.
.
. Results
. One thousand eight hundred sixteen studies were identified; 61 contributed to analyses. Pooled prevalences for PH using the consensus definition were 17% (95% CI, 14–20%; I2 = 99%) for 34 community cohorts, 19% (15–25%; I2 = 98%) for 23 primary care cohorts and 31% (15–50%; I2 = 0%) for 3 residential care or nursing homes cohorts (P = 0.16 between groups). By condition, prevalences were 20% (16–23%; I2 = 98%) with hypertension (20 cohorts), 21% (16–26%; I2 = 92%) with diabetes (4 cohorts), 25% (18–33%; I2 = 88%) with Parkinson’s disease (7 cohorts) and 29% (25–33%, I2 = 0%) with dementia (3 cohorts), compared to 14% (12–17%, I2 = 99%) without these conditions (P < 0.01 between groups). Multivariable meta-regression modelling identified increasing age and diabetes as predictors of PH (P < 0.01, P = 0.13, respectively; R2 = 36%). PH prevalence was not affected by blood pressure measurement device (P = 0.65) or sitting or supine resting position (P = 0.24), however, when the definition of PH did not fulfil the consensus description, but fell within its parameters, prevalence was underestimated (P = 0.01) irrespective of study quality (P = 0.04).
.
. Conclusions
. PH prevalence in populations relevant to primary care is substantial and the definition of PH used is important. Our findings emphasise the importance of considering checking for PH, particularly in vulnerable populations, to enable interventions to manage it. These data should contribute to future guidelines relevant to the detection and treatment of PH.
. PROSPERO:CRD42017075423.
.
Abstract.
Full text.
2020
Clark C, Warren F, Boddy K, McDonagh S, Moore S, Goddard J, Reed N, Turner M, Alzamora MT, Ramos Blanes R, et al (2020). Associations Between Systolic Interarm Differences in Blood Pressure and Cardiovascular Disease Outcomes and Mortality: Individual Participant Data Meta-Analysis, Development and Validation of a Prognostic Algorithm: the INTERPRESS-IPD Collaboration.
Hypertension,
n/a, 1-12.
Full text.
Lewis PS, Chapman N, Chowienczyk P, Clark C, Denver E, Lacy P, Martin U, McManus R, Neary A, Sheppard J, et al (2020). Correction: Oscillometric measurement of blood pressure: a simplified explanation. A technical note on behalf of the British and Irish Hypertension Society (Journal of Human Hypertension, (2019), 33, 5, (349-351), 10.1038/s41371-019-0196-9).
Journal of Human Hypertension,
34(3).
Abstract:
Correction: Oscillometric measurement of blood pressure: a simplified explanation. A technical note on behalf of the British and Irish Hypertension Society (Journal of Human Hypertension, (2019), 33, 5, (349-351), 10.1038/s41371-019-0196-9)
© 2020, the Author(s). This Article was originally published under Nature Research’s License to Publish, but has now been made available under a [CC BY 4.0] license. The PDF and HTML versions of the Article have been modified accordingly.
Abstract.
Clark CE, McDonagh STJ, McManus RJ, Worki BPM (2020). Measurement of blood pressure in people with atrial fibrillation (vol 33, pg 763, 2019).
JOURNAL OF HUMAN HYPERTENSION,
34(6), 476-476.
Author URL.
Sheppard JP, Lacy P, Lewis PS, Martin U (2020). Measurement of blood pressure in the leg—a statement on behalf of the British and Irish Hypertension Society.
Journal of Human Hypertension,
34(6), 418-419.
Full text.
Gomez-Cano M, Wiering B, Abel G, Campbell J, Clark C (2020). Medication adherence and clinical outcomes in dispensing and non-dispensing practices: a cross-sectional analysis.
British Journal of General Practice Full text.
Jordan AN, Anning C, Wilkes L, Ball C, Pamphilon N, Clark CE, Bellenger NG, Shore AC, Sharp ASP (2020). Rapid treatment of moderate to severe hypertension using a novel protocol in a single-centre, before and after interventional study.
J Hum Hypertens,
34(2), 165-175.
Abstract:
Rapid treatment of moderate to severe hypertension using a novel protocol in a single-centre, before and after interventional study.
Rapid treatment to target in hypertension may have beneficial effects on long-term outcomes. This has led to a new recommendation in the 2018 European hypertension guidelines for patients with grade II/III hypertension to be treated to target within three months. However, whether it is feasible and safe to quickly manage treatment-naïve grade II/III hypertension to target was unclear. We examined this using a single-centre before and after interventional study, treating newly diagnosed, never-treated, grade II/III hypertensive patients with a daytime average systolic ABP ≥ 150 mmHg to target within 18 weeks. The proportion at office target BP at 18 weeks was determined, together with office and ambulatory BP change from baseline to after the intervention. The protocol was designed to maximise medication adherence, including a low threshold for treatment adaptation. Safety was evaluated through close monitoring of adverse events and protocol discontinuation. Fifty-five participants were enrolled with 54 completing the protocol. 69 ± 12.3% were at office target BP at their final visit, despite a high average starting BP of 175/103 mmHg, as a consequence of significant reductions in both office and ambulatory BP. of those at office target BP, 51% were above target on ambulatory measurement. Adherence testing demonstrated that 92% of participants were adherent to treatment at their final visit. Therefore we conclude that the accelerated management of treatment-naïve grade II/III hypertension is feasible and safe to implement in routine practice and there is no evidence to suggest it causes harm. Further large-scale randomised studies of rapid, adaptive treatment, including a cost-effectiveness analysis, are required.
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Author URL.
Sheppard JP, Lacy P, Chapman N, Clark C, McManus RJ (2020). Reporting of the Meditech ABPM-06 ambulatory blood pressure device validation study. Blood Pressure Monitoring, 59-60.
Clark CE, Masoli J, Warren FC, Soothill J, Campbell JL (2020). Vitamin D and COVID-19 in older age: evidence versus expectations. British Journal of General Practice, 71(702), 10-11.
2019
Clark CE, McDonagh STJ, McManus RJ (2019). Accuracy of automated blood pressure measurements in the presence of atrial fibrillation: systematic review and meta-analysis.
J Hum Hypertens,
33(5), 352-364.
Abstract:
Accuracy of automated blood pressure measurements in the presence of atrial fibrillation: systematic review and meta-analysis.
Atrial fibrillation (AF) affects ~3% of the general population and is twice as common with hypertension. Validation protocols for automated sphygmomanometers exclude people with AF, raising concerns over accuracy of hypertension diagnosis or management, using out-of-office blood pressure (BP) monitoring, in the presence of AF. Some devices include algorithms to detect AF; a feature open to misinterpretation as offering accurate BP measurement with AF. We undertook this review to explore accuracy of automated devices, with or without AF detection, for measuring BP. We searched Medline and Embase to October 2018 for studies comparing automated BP measurement devices to a standard mercury sphygmomanometer contemporaneously. Data were extracted by two reviewers. Mean BP differences between devices and mercury were calculated, where not reported and compared; meta-analyses were undertaken where possible. We included 13 studies reporting 14 devices. Mean systolic and diastolic BP differences from mercury ranged from -3.1 to + 6.1/-4.6 to +9.0 mmHg. Considerable heterogeneity existed between devices (I2: 80 to 90%). Devices with AF detection algorithms appeared no more accurate for BP measurement with AF than other devices. A previous review concluded that oscillometric devices are accurate for systolic but not diastolic BP measurement in AF. The present findings do not support that conclusion. Due to heterogeneity between devices, they should be evaluated on individual performance. We found no evidence that devices with AF detection measure BP more accurately in AF than other devices. More home or ambulatory automated BP monitors require validation in populations with AF.
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McDonagh S, Clark C (2019). CVD risk factors: new evidence, new approaches?. Primary Care Cardiovascular Journal
Mcdonagh S, Norris B, Fordham AJ, Greenwood M, Richards SH, Campbell JL, Clark CE (2019). IMPACT OF INTER-ARM BLOOD PRESSURE DIFFERENCE ON CARDIOVASCULAR RISK ESTIMATION IN PRIMARY CARE.
Author URL.
Clark CE, McDonagh STJ, McManus RJ, Blood Pressure Measurement Working Party of the British and Irish Hypertension Society (2019). Measurement of blood pressure in people with atrial fibrillation.
J Hum Hypertens,
33(11), 763-765.
Author URL.
Lewis PS, Chapman N, Chowienczyk P, Clark C, Denver E, Lacy P, Martin U, McManus R, Neary A, Sheppard J, et al (2019). Oscillometric measurement of blood pressure: a simplified explanation. A technical note on behalf of the British and Irish Hypertension Society. Journal of Human Hypertension, 33(5), 349-351.
2018
Clark CE, Thomas D, Warren F, Llewellyn D, Ferrucci L, Campbell J (2018). Detecting Risks of Postural Hypotension (DROP): derivation and validation of a prediction score for primary care. BMJ Open
Clark CE, Sims L (2018). Hypertension care: sharing the burden with pharmacists.
Br J Gen Pract,
68(675), 458-459.
Author URL.
Clark CE (2018). Nurse led interventions in Hypertension. In Burnier M (Ed)
Drug Adherence in Hypertension and Cardiovascular Protection, Springer.
Abstract:
Nurse led interventions in Hypertension
Abstract.
Full text.
McManus R, Lacy P, Clark C, Chapman N, Lewis P (2018). Reporting of blood pressure monitor validation studies. Blood Pressure Monitoring, 23(4), 214-215.
2017
Clark CE, Boddy K, Warren FC, Taylor RS, Aboyans V, Cloutier L, McManus RJ, Shore AC, Campbell JL (2017). Associations between interarm differences in blood pressure and cardiovascular disease outcomes: protocol for an individual patient data meta-analysis and development of a prognostic algorithm.
BMJ Open,
7(6).
Abstract:
Associations between interarm differences in blood pressure and cardiovascular disease outcomes: protocol for an individual patient data meta-analysis and development of a prognostic algorithm.
INTRODUCTION: Individual cohort studies in various populations and study-level meta-analyses have shown interarm differences (IAD) in blood pressure to be associated with increased cardiovascular and all-cause mortality. However, key questions remain, such as follows: (1) What is the additional contribution of IAD to prognostic risk estimation for cardiovascular and all-cause mortality? (2) What is the minimum cut-off value for IAD that defines elevated risk? (3) is there a prognostic value of IAD and do different methods of IAD measurement impact on the prognostic value of IAD? We aim to address these questions by conducting an individual patient data (IPD) meta-analysis. METHODS AND ANALYSIS: This study will identify prospective cohort studies that measured blood pressure in both arms during recruitment, and invite authors to contribute IPD datasets to this collaboration. All patient data received will be combined into a single dataset. Using one-stage meta-analysis, we will undertake multivariable time-to-event regression modelling, with the aim of developing a new prognostic model for cardiovascular risk estimation that includes IAD. We will explore variations in risk contribution of IAD across predefined population subgroups (eg, hypertensives, diabetics), establish the lower limit of IAD that is associated with additional cardiovascular risk and assess the impact of different methods of IAD measurement on risk prediction. ETHICS AND DISSEMINATION: This study will not include any patient identifiable data. Included datasets will already have ethical approval and consent from their sponsors. Findings will be presented to international conferences and published in peer reviewed journals, and we have a comprehensive dissemination strategy in place with integrated patient and public involvement. PROSPERO REGISTRATION NUMBER: CRD42015031227.
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Schwartz CL, Clark C, Koshiaris C, Gill PS, Greenfield SM, Haque SM, Heer G, Johal A, Kaur R, Mant J, et al (2017). Interarm Difference in Systolic Blood Pressure in Different Ethnic Groups and Relationship to the “White Coat Effect”: a Cross-Sectional Study. American Journal of Hypertension, 30(9), 884-891.
Clark CE (2017). The interarm blood pressure difference: Do we know enough yet?.
J Clin Hypertens (Greenwich),
19(5), 462-465.
Author URL.
Mejzner N, Clark CE, Smith LF, Campbell JL (2017). Trends in the diagnosis and management of hypertension: repeated primary care survey in South West England.
Br J Gen Pract,
67(658), e306-e313.
Abstract:
Trends in the diagnosis and management of hypertension: repeated primary care survey in South West England.
BACKGROUND: Previous surveys identified a shift to nurse-led care in hypertension in 2010. In 2011 the National Institute for Health and Care Excellence (NICE) recommended ambulatory (ABPM) or home (HBPM) blood pressure (BP) monitoring for diagnosis of hypertension. AIM: to survey the organisation of hypertension care in 2016 to identify changes, and to assess uptake of NICE diagnostic guidelines. DESIGN AND SETTING: Questionnaires were distributed to all 305 general practices in South West England. METHOD: Responses were compared with previous rounds (2007 and 2010). Data from the 2015 Quality and Outcomes Framework (QOF) were used to compare responders with non-responders, and to explore associations of care organisation with QOF achievement. RESULTS: One-hundred-and-seventeen practices (38%) responded. Responders had larger list sizes and greater achievement of the QOF target BP ≤150/90 mmHg. Healthcare assistants (HCAs) now monitor BP in 70% of practices, compared with 37% in 2010 and 19% in 2007 (P
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2016
Clark CE, Taylor RS, Butcher I, Stewart MC, Price J, Fowkes FGR, Shore AC, Campbell JL (2016). Inter-arm blood pressure difference and mortality: a cohort study in an asymptomatic primary care population at elevated cardiovascular risk.
Br J Gen Pract,
66(646), e297-e308.
Abstract:
Inter-arm blood pressure difference and mortality: a cohort study in an asymptomatic primary care population at elevated cardiovascular risk.
BACKGROUND: Differences in blood pressure between arms are associated with increased cardiovascular mortality in cohorts with established vascular disease or substantially elevated cardiovascular risk. AIM: to explore the association of inter-arm difference (IAD) with mortality in a community-dwelling cohort that is free of cardiovascular disease. DESIGN AND SETTING: Cohort analysis of a randomised controlled trial in central Scotland, from April 1998 to October 2008. METHOD: Volunteers from Lanarkshire, Glasgow, and Edinburgh, free of pre-existing vascular disease and with an ankle-brachial index ≤0.95, had systolic blood pressure measured in both arms at recruitment. Inter-arm blood pressure differences were calculated and examined for cross-sectional associations and differences in prospective survival. Outcome measures were cardiovascular events and all-cause mortality during mean follow-up of 8.2 years. RESULTS: Based on a single pair of measurements, 60% of 3350 participants had a systolic IAD ≥5 mmHg and 38% ≥10 mmHg. An IAD ≥5 mmHg was associated with increased cardiovascular mortality (adjusted hazard ratio [HR] 1.91, 95% confidence interval [CI] = 1.19 to 3.07) and all-cause mortality (adjusted HR 1.44, 95% CI = 1.15 to 1.79). Within the subgroup of 764 participants who had hypertension, IADs of ≥5 mmHg or ≥10 mmHg were associated with both cardiovascular mortality (adjusted HR 2.63, 95% CI = 0.97 to 7.02, and adjusted HR 2.96, 95% CI = 1.27 to 6.88, respectively) and all-cause mortality (adjusted HR 1.67, 95% CI = 1.05 to 2.66, and adjusted HR 1.63, 95% CI = 1.06 to 2.50, respectively). IADs ≥15 mmHg were not associated with survival differences in this population. CONCLUSION: Systolic IADs in blood pressure are associated with increased risk of cardiovascular events, including mortality, in a large cohort of people free of pre-existing vascular disease.
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Clark CE, Taylor RS, Shore AC, Campbell JL (2016). Prevalence of systolic inter-arm differences in blood pressure for different primary care populations: systematic review and meta-analysis.
Br J Gen Pract,
66(652), e838-e847.
Abstract:
Prevalence of systolic inter-arm differences in blood pressure for different primary care populations: systematic review and meta-analysis.
BACKGROUND: Various prevalence figures have been reported for inter-arm differences in blood pressure (IAD); variation may be explained by differing population vascular risk and by measurement method. AIM: to review the literature to derive robust estimates of IAD prevalence relevant to community populations. DESIGN AND SETTING: Systematic review and meta-analysis. METHOD: MEDLINE, Embase, and CINAHL were searched for cross-sectional studies likely to represent general or primary care populations, reporting prevalence of IAD and employing a simultaneous method of measurement. Using study-level data, pooled estimates of mean prevalence of systolic IADs were calculated and compared using a random effects model. RESULTS: Eighty IAD studies were identified. Sixteen met inclusion criteria: pooled estimates of prevalence for systolic IAD ≥10 mmHg were 11.2% (95% confidence interval [CI] = 9.1 to 13.6) in hypertension, 7.4% (95% CI = 5.8 to 9.2) in diabetes, and 3.6% (95% CI = 2.3 to 5.0) for a general adult population (P
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Clark CE (2016). What’s new in hypertension?.
Abstract:
What’s new in hypertension?
This module describes recent developments in the management of hypertension, and the practical implications for doctors working in primary care. It covers evidence about measurement of blood pressure, primary prevention, the treatment of mild hypertension, early intensive treatment, and treatment of special groups of patients.
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2015
Clark C, Shore A, Taylor R, Campbell J (2015). 1C.08: THE INTER-ARM DIFFERENCE IN BLOOD PRESSURE AND MORTALITY: SYSTEMATIC REVIEW AND META-ANALYSIS.
J Hypertens,
33 Suppl 1Abstract:
1C.08: THE INTER-ARM DIFFERENCE IN BLOOD PRESSURE AND MORTALITY: SYSTEMATIC REVIEW AND META-ANALYSIS.
OBJECTIVE: We previously reported the association of inter-arm differences in blood pressure measurements (IAD) with increased cardiovascular and all-cause mortality. Several new large cohorts have been reported since our 2012 meta-analysis. We have therefore updated our meta-analyses to take account of these new data. DESIGN AND METHOD: Systematic review and meta-analysis: Medline, Embase and CINAHL were searched for studies reporting survival data in association with IAD. Study level hazard ratios (HR) were extracted for systolic IADs >=10mmHg and >=15mmHg, and pooled using generic inverse variance in a random effects model. Statistical heterogeneity was assessed using the I statistic. RESULTS: Searches to 12th November 2014 identified 3514 unique citations. Eighty full texts were assessed, and 13 studies (reporting data for 14 unique cohorts) contributed to the analyses, Median follow up ranged from 3 to 13 years. Five cohorts employed a simultaneous method of IAD measurement; the remainder used sequential measurements. Ten cohorts were recruited from community populations, including one hypertensive and one diabetic cohort. Four were selected hospital cohorts at increased vascular risk.Cardiovascular mortality was greater with an IAD >=10mmHg (HR 1.9 (95%CI 1.3 to 2.6; 7 cohorts, 13815 participants; I = 45%) and an IAD >=15mmHg (HR 1.7 (1.2 to 2.4; 9 cohorts; 18241 participants; I = 30%). For all-cause mortality HRs were 1.4 (1.2 to 1.8; 10 cohorts, 17709 participants; I = 62%) for IAD >=10mmHg and 1.4 (1.1 to 1.7; 12 cohorts, 18714 participants; I = 46%) for IAD >=15mmHg. Heterogeneity between studies could be accounted for by stratification according to underlying population cardiovascular risk, with higher HRs seen in populations at elevated risk; cardiovascular mortality with an IAD >=10mmHg: HR 1.4 (1.1 to 1.8; I = 0%) for community based cohorts compared to 3.8 (2.2 to 6.6; I = 0%) for those at elevated cardiovascular risk (p = 0.001; Figure).(Figure is included in full-text article.) CONCLUSIONS: : New studies confirming the association of an IAD with increased cardiovascular and all-cause mortality are consistent with previously published findings. Risks associated with an IAD rise in association with the underlying vascular risk of the population studied.
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Clark CE (2015). Difference in blood pressure measurements between arms: methodological and clinical implications.
Curr Pharm Des,
21(6), 737-743.
Abstract:
Difference in blood pressure measurements between arms: methodological and clinical implications.
Differences in blood pressure measurements between arms are commonly encountered in clinical practice. If such differences are not excluded they can delay the diagnosis of hypertension and can lead to poorer control of blood pressure levels. Differences in blood pressure measurements between arms are associated cross sectionally with other signs of vascular disease such as peripheral arterial disease or cerebrovascular disease. Differences are also associated prospectively with increased cardiovascular mortality and morbidity and all cause mortality. Numbers of publications on inter-arm difference are rising year on year, indicating a growing interest in the phenomenon. The prevalence of an inter-arm difference varies widely between reports, and is correlated with the underlying cardiovascular risk of the population studied. Prevalence is also sensitive to the method of measurement used. This review discusses the prevalence of an inter-arm difference in different populations and addresses current best practice for the detection and the measurement of a difference. The evidence for clinical and for vascular associations of an inter-arm difference is presented in considering the emerging role of an inter-arm blood pressure difference as a novel risk factor for increased cardiovascular morbidity and mortality. Competing aetiological explanations for an inter-arm difference are explored, and gaps in our current understanding of this sign, along with areas in need of further research, are considered.
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Clark CE, Aboyans V (2015). Interarm blood pressure difference: more than an epiphenomenon.
Nephrol Dial Transplant,
30(5), 695-697.
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Jenkinson CE, Asprey A, Clark CE, Richards SH (2015). Patients' willingness to attend the NHS cardiovascular health checks in primary care: a qualitative interview study.
BMC Family Practice,
16(1).
Abstract:
Patients' willingness to attend the NHS cardiovascular health checks in primary care: a qualitative interview study
© 2015 Jenkinson et al.; licensee BioMed Central. Background: the NHS Cardiovascular Health Check (NHSHC) programme was introduced in England in 2009 to reduce cardiovascular disease mortality and morbidity for all patients aged 40 to 74 years old. Programme cost-effectiveness was based on an assumed uptake of 75% but current estimates of uptake in primary care are less than 50%. The purpose of this study was to identify factors influencing patients' willingness to attend an NHSHC. For those who attended, their views, experiences and their future willingness to engage in the programme were explored. Method: Telephone or face-to-face interviews were conducted with patients who had recently been invited for an NHSHC by a letter from four general practices in Torbay, England. Patients were purposefully sampled (by gender, age, attendance status). Interviews were audio recorded, transcribed verbatim and analysed thematically. Results: 17 attendees and 10 non-attendees were interviewed. Patients who attended an NHSHC viewed it as worthwhile. Proactive attitudes towards their health, a desire to prevent disease before they developed symptoms, and a willingness to accept screening and health check invitations motivated many individuals to attend. Non-attendees cited not seeing the NHSHC as a priority, or how it differed from regular monitoring already received for other conditions as barriers to attendance. Some non-attendees actively avoided GP practices when feeling well, while others did not want to waste health professionals' time. Misunderstandings of what the NHSHC involved and negative views of what the likely outcome might be were common. Conclusion: While a minority of non-attendees simply had made an informed choice not to have an NHSHC, improving the clarity and brevity of invitational materials, better advertising, and simple administrative interventions such as sending reminder letters, have considerable potential to improve NHSHC uptake.
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2014
Clark CE, Horvath IA, Taylor RS, Campbell JL (2014). Doctors record higher blood pressures than nurses: systematic review and meta-analysis.
Br J Gen Pract,
64(621), e223-e232.
Abstract:
Doctors record higher blood pressures than nurses: systematic review and meta-analysis.
BACKGROUND: the magnitude of the 'white coat effect', the alerting rise in blood pressure, is greater for doctors than nurses. This could bias interpretation of studies on nurse-led care in hypertension, and risks overestimating or overtreating high blood pressure by doctors in clinical practice. AIM: to quantify differences between blood pressure measurements made by doctors and nurses. DESIGN AND SETTING: Systematic review and meta-analysis using searches of MEDLINE, CENTRAL, CINAHL, Embase, journal collections, and conference abstracts. METHOD: Studies in adults reporting mean blood pressures measured by doctors and nurses at the same visit were selected, and mean blood pressures extracted, by two reviewers. Study risk of bias was assessed using modified Cochrane criteria. Outcomes were pooled across studies using random effects meta-analysis. RESULTS: in total, 15 studies (11 hypertensive; four mixed hypertensive and normotensive populations) were included from 1899 unique citations. Compared with doctors' measurements, nurse-measured blood pressures were lower (weighted mean differences: systolic -7.0 [95% confidence interval {CI} = -4.7 to -9.2] mmHg, diastolic -3.8 [95% CI = -2.2 to -5.4] mmHg). For studies at low risk of bias, differences were lower: systolic -4.6 (95% CI = -1.9 to -7.3) mmHg; diastolic -1.7 (95% CI = -0.1 to -3.2) mmHg. White coat hypertension was diagnosed more frequently based on doctors' than on nurses' readings: relative risk 1.6 (95% CI =1.2 to 2.1). CONCLUSIONS: the white coat effect is smaller for blood pressure measurements made by nurses than by doctors. This systematic difference has implications for hypertension diagnosis and management. Caution is required in pooling data from studies using both nurse- and doctor-measured blood pressures.
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Clark CE, Steele AM, Taylor RS, Shore AC, Ukoumunne OC, Campbell JL (2014). Interarm Blood Pressure Difference in People with Diabetes: Measurement and Vascular and Mortality Implications a Cohort Study.
DIABETES CARE,
37(6), 1613-1620.
Author URL.
2013
Clark CE, Smith LFP, Glynn LG, Taylor RS, Campbell JL, Cloutier L (2013). Allied health professional-led interventions for improving control of blood pressure in patients with hypertension: systematic review and meta-analysis.
JOURNAL OF HUMAN HYPERTENSION,
27(10), 641-641.
Author URL.
Clark CE (2013). Four-Limb Blood Pressure Measurement a Research Tool Looking for Clinical Use.
HYPERTENSION,
61(6), 1146-1147.
Author URL.
Clark CE, Steele AM, Taylor RS, Shore AC, Ukoumunne OC, Campbell JL (2013). The inter-arm blood pressure difference in people with diabetes: measurement, vascular, and mortality implications.
JOURNAL OF HUMAN HYPERTENSION,
27(10), 645-645.
Author URL.
2012
Campbell J, Clark CE, Taylor RS, Shore AC, Ukoumunne OC (2012). Association of a difference in systolic blood pressure between arms with vascular disease and mortality: a systematic review and meta analysis. Lancet
Clark CE, Taylor RS, Shore AC, Ukoumunne OC, Campbell JL (2012). Association of a difference in systolic blood pressure between arms with vascular disease and mortality: a systematic review and meta-analysis (vol 379, pg 905, 2012).
LANCET,
380(9838), 218-218.
Author URL.
Clark CE, Taylor RS, Shore AC, Ukoumunne OC, Campbell JL (2012). Erratum: Association of a diff erence in systolic blood pressure between arms with vascular disease and mortality: a systematic review and meta-analysis (The Lancet (2012) 379 (905-914). The Lancet, 380(9838).
Clark CE, Taylor RS, Shore AC, Ukoumunne OC, Campbell JL (2012). Interarm blood pressure difference and vascular disease - Authors reply. The Lancet, 380(9836), 24-25.
Clark CE, Taylor RS, Shore AC, Ukoumunne OC, Campbell JL (2012). Interarm blood pressure difference and vascular disease Reply.
LANCET,
380(9836), 24-25.
Author URL.
Clark C, Smith L, Taylor R, Campbell J (2012). Response to Carey and Courtenay. Nurse-led interventions used to improve control of high blood pressure in people with diabetes: a systematic review and meta-analysis. Diabet Med, 29(1), 155-156.
Clark CE, Taylor RS, Shore AC, Campbell JL (2012). The difference in blood pressure readings between arms and survival: primary care cohort study.
BMJ,
344Abstract:
The difference in blood pressure readings between arms and survival: primary care cohort study.
OBJECTIVE: to determine whether a difference in systolic blood pressure readings between arms can predict a reduced event free survival after 10 years. DESIGN: Cohort study. SETTING: Rural general practice in Devon, United Kingdom. PARTICIPANTS: 230 people receiving treatment for hypertension in primary care. INTERVENTION: Bilateral blood pressure measurements recorded at three successive surgery attendances. MAIN OUTCOME MEASURES: Cardiovascular events and deaths from all causes during a median follow-up of 9.8 years. RESULTS: at recruitment 24% (55/230) of participants had a mean interarm difference in systolic blood pressure of 10 mm Hg or more and 9% (21/230) of 15 mm Hg or more; these differences were associated with an increased risk of all cause mortality (adjusted hazard ratio 3.6, 95% confidence interval 2.0 to 6.5 and 3.1, 1.6 to 6.0, respectively). The risk of death was also increased in 183 participants without pre-existing cardiovascular disease with an interarm difference in systolic blood pressure of 10 mm Hg or more or 15 mm Hg or more (2.6, 1.4 to 4.8 and 2.7, 1.3 to 5.4). An interarm difference in diastolic blood pressure of 10 mm Hg or more was weakly associated with an increased risk of cardiovascular events or death. CONCLUSIONS: Differences in systolic blood pressure between arms can predict an increased risk of cardiovascular events and all cause mortality over 10 years in people with hypertension. This difference could be a valuable indicator of increased cardiovascular risk. Bilateral blood pressure measurements should become a routine part of cardiovascular assessment in primary care.
Abstract.
Author URL.
Full text.
Clark CE, McManus R (2012). The use of highly structured care to achieve blood pressure targets.
BMJ-BRITISH MEDICAL JOURNAL,
345 Author URL.
2011
Clark CE (2011). Inter-arm blood pressure measurement needs to be practical and accurate.
Am J Hypertens,
24(11), 1189-1190.
Author URL.
Clark CE, Smith LFP, Harding G, Taylor RS, Campbell JL (2011). Nurse led hypertension clinics: evolving ahead of the evidence?.
JOURNAL OF HUMAN HYPERTENSION,
25(10), 630-630.
Author URL.
Clark CE, Smith LFP, Taylor RS, Campbell JL (2011). Nurse-led interventions used to improve control of high blood pressure in people with diabetes: a systematic review and meta-analysis.
Diabet Med,
28(3), 250-261.
Abstract:
Nurse-led interventions used to improve control of high blood pressure in people with diabetes: a systematic review and meta-analysis.
BACKGROUND: Previous reviews demonstrate uncertainty about the effectiveness of nurse-led interventions in the management of hypertension. No specific reviews in diabetes have been identified. We have systematically reviewed the evidence for effectiveness of nurse-led interventions for people with diabetes mellitus. METHODS: in this systematic review and meta-analysis, searches of Medline, Embase, CINAHL and the Cochrane Central Trials register were undertaken to identify studies comparing any intervention conducted by nurses in managing hypertension in diabetes with usual doctor-led care. Additional citations were identified from papers retrieved and correspondence with authors. Outcome measures were absolute systolic and diastolic blood pressure, change in blood pressure, proportions achieving study target blood pressure and proportions prescribed anti-hypertensive medication. RESULTS: Eleven studies were identified. Interventions included adoption of treatment algorithms, nurse-led clinics and nurse prescribing. Meta-analysis showed greater reductions in blood pressure in favour of any nurse-led interventions (systolic weighted mean difference -5.8 mmHg, 95% CI -9.6 to -2.0; diastolic weighted mean difference -4.2 mmHg, 95% CI -7.6 to -0.7) compared with usual doctor-led care. No overall superiority in achievement of study targets or in the use of medication was evident for any nurse-based interventions over doctor-led care. CONCLUSIONS: There is some evidence for improved blood pressure outcomes with nurse-led interventions for hypertension in people with diabetes compared with doctor-led care. Nurse-based interventions require an algorithm to structure care and there is some preliminary evidence for better outcomes with nurse prescribing. Further work is needed to elucidate which nurse-led interventions are most effective.
Abstract.
Author URL.
Clark CE, Taylor RS, Shore AC, Campbell JL (2011). Systolic inter-arm blood pressure difference is associated with increased cardiovascular and all-cause mortality in hypertension: meta-analysis.
JOURNAL OF HUMAN HYPERTENSION,
25(10), 633-633.
Author URL.
2010
Clark CE, Arnold E, Lasserson TJ, Wu T (2010). Herbal interventions for chronic asthma in adults and children: a systematic review and meta-analysis.
Prim Care Respir J,
19(4), 307-314.
Abstract:
Herbal interventions for chronic asthma in adults and children: a systematic review and meta-analysis.
AIMS: to assess the efficacy of herb and plant extracts in the management of asthma. METHOD: Systematic review and meta-analysis. Multiple database searches identified randomised placebo controlled trials of herbal interventions reporting at least one primary outcome measure. Where possible data were combined for meta-analysis. Primary outcome measures were lung function, exacerbations and reduction in corticosteroid use. Secondary outcome measures were symptoms and symptom scores, use of reliever medications, changes in rates of consultation and adverse effects. RESULTS: Twenty-six studies reporting on 20 herbal preparations were included. Two of six studies reporting change in FEV1 were positive. Little data was available on frequency of exacerbations. For primary outcomes single studies of Boswellia, Mai-Men-Dong-Tang, Pycnogenol, Jia-Wei-Si-Jun-Zi-Tang and Tylophora indica showed potential to improve lung function, and a study of 1.8-Cineol (eucalyptol) showed reduced daily oral steroid dosage. CONCLUSIONS: Improvements in symptoms were not strongly supported by objective changes. Most trials were of small sample size, short duration, and poor methodology. Further adequately powered trials are needed to assess these compounds. Such trials should conform to CONSORT guidance, report standardised spirometry, and use validated symptom and severity scores. No recommendations for herbal treatment of asthma can be made from the current evidence.
Abstract.
Author URL.
Clark CE, Smith LFP, Taylor RS, Campbell JL (2010). Nurse led interventions to improve control of blood pressure in people with hypertension: Systematic review and meta-analysis.
BMJ (Online),
341(7771).
Abstract:
Nurse led interventions to improve control of blood pressure in people with hypertension: Systematic review and meta-analysis
Objective: to review trials of nurse led interventions for hypertension in primary care to clarify the evidence base, establish whether nurse prescribing is an important intervention, and identify areas requiring further study. Design: Systematic review and meta-analysis. Data sources: Ovid Medline, Cochrane Central Register of Controlled Trials, British Nursing Index, Cinahl, Embase, Database of Abstracts of Reviews of Effects, and the NHS Economic Evaluation Database. Study selection: Randomised controlled trials of nursing interventions for hypertension compared with usual care in adults. Data extraction: Systolic and diastolic blood pressure, percentages reaching target blood pressure, and percentages taking antihypertensive drugs. Intervention effects were calculated as relative risks or weighted mean differences, as appropriate, and sensitivity analysis by study quality was undertaken. Data synthesis: Compared with usual care, interventions that included a stepped treatment algorithm showed greater reductions in systolic blood pressure (weighted mean difference -8.2 mm Hg, 95% confidence interval -11.5 to -4.9), nurse prescribing showed greater reductions in blood pressure (systolic -8.9 mm Hg, -12.5 to -5.3 and diastolic -4.0 mm Hg, -5.3 to -2.7), telephone monitoring showed higher achievement of blood pressure targets (relative risk 1.24, 95% confidence interval 1.08 to 1.43), and community monitoring showed greater reductions in blood pressure (weighted mean difference, systolic -4.8 mm Hg, 95% confidence interval -7.0 to -2.7 and diastolic -3.5 mm Hg, -4.5 to -2.5). Conclusions: Nurse led interventions for hypertension require an algorithm to structure care. Evidence was found of improved outcomes with nurse prescribers from non-UK healthcare settings. Good quality evidence from UK primary health care is insufficient to support widespread employment of nurses in the management of hypertension within such healthcare systems.
Abstract.
Full text.
Clark CE, Smith LFP, Taylor RS, Campbell JL (2010). Nurse led interventions to improve control of blood pressure in people with hypertension: systematic review and meta-analysis.
BMJ,
341Abstract:
Nurse led interventions to improve control of blood pressure in people with hypertension: systematic review and meta-analysis.
OBJECTIVE: to review trials of nurse led interventions for hypertension in primary care to clarify the evidence base, establish whether nurse prescribing is an important intervention, and identify areas requiring further study. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Ovid Medline, Cochrane Central Register of Controlled Trials, British Nursing Index, Cinahl, Embase, Database of Abstracts of Reviews of Effects, and the NHS Economic Evaluation Database. STUDY SELECTION: Randomised controlled trials of nursing interventions for hypertension compared with usual care in adults. DATA EXTRACTION: Systolic and diastolic blood pressure, percentages reaching target blood pressure, and percentages taking antihypertensive drugs. Intervention effects were calculated as relative risks or weighted mean differences, as appropriate, and sensitivity analysis by study quality was undertaken. DATA SYNTHESIS: Compared with usual care, interventions that included a stepped treatment algorithm showed greater reductions in systolic blood pressure (weighted mean difference -8.2 mm Hg, 95% confidence interval -11.5 to -4.9), nurse prescribing showed greater reductions in blood pressure (systolic -8.9 mm Hg, -12.5 to -5.3 and diastolic -4.0 mm Hg, -5.3 to -2.7), telephone monitoring showed higher achievement of blood pressure targets (relative risk 1.24, 95% confidence interval 1.08 to 1.43), and community monitoring showed greater reductions in blood pressure (weighted mean difference, systolic -4.8 mm Hg, 95% confidence interval -7.0 to -2.7 and diastolic -3.5 mm Hg, -4.5 to -2.5). CONCLUSIONS: Nurse led interventions for hypertension require an algorithm to structure care. Evidence was found of improved outcomes with nurse prescribers from non-UK healthcare settings. Good quality evidence from UK primary health care is insufficient to support widespread employment of nurses in the management of hypertension within such healthcare systems.
Abstract.
Author URL.
Full text.
Clark CE, Smith LFP, Taylor RS, Campbell JL (2010). Nurse-led management of hypertension.
Br J Gen Pract,
60(572).
Author URL.
2009
Clark CE, Campbell JL (2009). Hypertension guidelines.
BRITISH JOURNAL OF GENERAL PRACTICE,
59(563), 448-449.
Author URL.
Clark CE, Greaves CJ, Evans PH, Dickens A, Campbell JL (2009). Inter-arm blood pressure difference in type 2 diabetes: a barrier to effective management?.
Br J Gen Pract,
59(563), 428-432.
Abstract:
Inter-arm blood pressure difference in type 2 diabetes: a barrier to effective management?
BACKGROUND: Previous studies have identified a substantial prevalence of a blood pressure difference between arms in various populations, but not patients with type 2 diabetes. Recognition of such a difference would be important as a potential cause of underestimation of blood pressure. AIM: to measure prevalence of an inter-arm blood pressure difference in patients with type 2 diabetes, and to estimate how frequently blood pressure measurements could be erroneously underestimated if an inter-arm difference is unrecognised. DESIGN OF STUDY: Cross-sectional study. SETTING: Five surgeries covered by three general practices, Devon, England. METHOD: Patients with type 2 diabetes underwent bilateral simultaneous blood pressure measurements using a validated protocol. Mean blood pressures were calculated for each arm to derive mean systolic and diastolic differences, and to estimate point prevalence of predefined magnitudes of difference. RESULTS: a total of 101 participants were recruited. Mean age was 66 years (standard deviation [SD] = 13.9 years); 59% were male, and mean blood pressure was 138/79 mmHg (SD = 15/10 mmHg). Ten participants (10%; 95% confidence interval [CI] = 4 to 16) had a systolic inter-arm difference > or =10 mmHg; 29 (29%; 95% CI = 20 to 38) had a diastolic difference >/=5 mmHg; and three (3%; 95% CI = 0 to 6) a diastolic difference > or =10 mmHg. No confounding variable was observed to account for the magnitude of an inter-arm difference. CONCLUSION: a systolic inter-arm difference > or =10 mmHg was observed in 10% of patients with diabetes. Failure to recognise this would misclassify half of these as normotensive rather than hypertensive using the lower-reading arm. New patients with type 2 diabetes should be screened for an inter-arm blood pressure difference.
Abstract.
Author URL.
2008
Arnold E, Clark CE, Lasserson TJ, Wu T (2008). Herbal interventions for chronic asthma in adults and children.
Cochrane Database of Systematic Reviews(1).
Abstract:
Herbal interventions for chronic asthma in adults and children
Background: Herb and plant based preparations are a popular treatment for asthma, although there remain concerns as to their efficacy and safety. In Western societies, motivations for using such treatments may be both positive and negative, with their perceived safety and dissatisfaction with conventional medicine among them. In China such treatments are more commonly used and many compounds considered 'conventional' are derived from herbs or plants. Objectives: to assess the efficacy and safety of herb and plant extracts in the management of chronic asthma. Search strategy: the Cochrane Airways Group Trials Register, CENTRAL, MEDLINE, EMBASE and AMED were searched with pre-defined terms. Searches are current as of February 2007. Selection criteria: Randomised placebo controlled trials of any herb or plant extract were eligible. Study participants had to have a primary diagnosis of asthma. Studies in both adults and children were eligible for the review. Data collection and analysis: Two reviewers assessed studies for suitability. Data were extracted and double-checked. Main results: Twenty-seven studies (29 experimental groups) met the review entry criteria, randomising a total of 1925 participants. The studies identified assessed the effects of 21 different herbal preparations. Study quality varied considerably, and the sample sizes were often small. For primary outcomes (exacerbations, steroids use and lung function measurements): Two out of six studies reporting change in FEV1 were positive, with very few data available on the frequency of exacerbations. One study which did report these data was negative. Health-related quality of life was only measured in one trial. Authors' conclusions: the evidence base for the effects of herbal treatments is hampered by the variety of treatments assessed, poor reporting quality of the studies and lack of available data. The data that are available from the studies provide only a small insight into the long-term efficacy and harm profiles of these treatments. The absence of common endpoint measurements limits the validity of our findings further. Positive findings in this review warrant additional well-designed trials in this area. Copyright © 2008 the Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
Abstract.
Clark CE, Campbell JL (2008). The interarm blood pressure difference.
HYPERTENSION,
52(2), E15-E15.
Author URL.
2007
Clark CE (2007). Screening for peripheral vascular disease [5]. British Journal of General Practice, 57(541).
Clark CE, Campbell JL, Powell RJ, Thompson JF (2007). The inter-arm blood pressure difference and peripheral vascular disease: cross-sectional study.
Fam Pract,
24(5), 420-426.
Abstract:
The inter-arm blood pressure difference and peripheral vascular disease: cross-sectional study.
BACKGROUND: a blood pressure (BP) difference between the upper limbs is often encountered in primary care. Knowledge of its prevalence and importance in the accurate measurement of BP is poor, representing a source of error. Current hypertension guidelines do not emphasize this. OBJECTIVES: to establish the prevalence of an inter-arm blood pressure difference (IAD) and explore its association with other indicators of peripheral vascular disease (PVD) in a hypertensive primary care population. METHODS: This was a cross-sectional study. Primary care, one rural general practice, was the setting of the study. The methods were controlled simultaneous measurement of brachial BPs, ankle-brachial pressure index (ABPI) and tiptoe stress testing in 94 subjects. RESULTS: in all, 18 of 94 [19%, 95% confidence interval (CI) 11-27%] subjects had mean systolic inter-arm difference (sIAD) > or =10 mmHg and seven of 94 (7%, 95% CI 2-12%) had mean diastolic inter-arm difference (dIAD) > or =10 mmHg. Nineteen of 91 (20%, 95% CI 12-28%) had a reduced ABPI. or =20%. CONCLUSIONS: an IAD and asymptomatic PVD are common in a primary care hypertensive population. Magnitude of the IAD is inversely correlated with ABPI, supporting the hypotheses that IADs are causally linked to PVD, and that IAD is a useful marker for the presence of PVD. Consequently, detection of an IAD should prompt the clinician to screen subjects for other signs of vascular disease and target them for aggressive cardiovascular risk factor modification.
Abstract.
Author URL.
Clark CE, Campbell JL, Powell RJ (2007). The interarm blood pressure difference as predictor of cardiovascular events in patients with hypertension in primary care: cohort study.
J Hum Hypertens,
21(8), 633-638.
Abstract:
The interarm blood pressure difference as predictor of cardiovascular events in patients with hypertension in primary care: cohort study.
Objectives of this study were to measure the prevalence of a difference in blood pressure (BP) between arms and determine whether a difference is associated with increased risk of cardiovascular events or death. A prospective cohort study of 247 patients with hypertension was undertaken in one rural general practice in England. The main outcome measures were mean difference in BP between arms and new episodes of myocardial infarction, cerebrovascular event, onset of angina or peripheral vascular disease or death. A total of 57/247 (23%) patients had a mean difference in systolic BP between arms of >or=10 mm Hg and 8/247 (3%) had a mean difference of >or=20 mm Hg. A total of 15/247 (6%) patients had a mean difference in diastolic BP between arms of >or=10 mm Hg. Survival analysis after 4.7 years (range 3.3-5.9) showed a shorter mean survival time without event or death for patients with a difference in systolic BP of >or=10 mm Hg compared with a difference of
Abstract.
Author URL.
2006
Clark CE, Campbell JL, Evans PH, Millward A (2006). Prevalence and clinical implications of the inter-arm blood pressure difference: a systematic review.
J Hum Hypertens,
20(12), 923-931.
Abstract:
Prevalence and clinical implications of the inter-arm blood pressure difference: a systematic review.
A blood pressure (BP) difference between arms was first reported over 100 years ago. Knowledge of its prevalence and relevance to the accurate measurement of BP remains poor. Current hypertension guidelines do not emphasise it. The objectives of this study were to establish the best estimate of prevalence of the inter-arm difference (IAD) in the population, to consider its implications for accurate BP measurement and treatment, and to discuss its aetiology and potential as a risk marker for cardiovascular disease. Systematic literature review was carried out. The data sources were Medline EMBASE and CINAHL databases, and Index of Theses. Studies reporting prevalence rates of IAD were retrieved and considered for inclusion against explicit methodological criteria. Point prevalence rates were extracted and weighted mean prevalence rates calculated. The main outcome measures were weighted mean prevalences of systolic IAD > or =10 and > or =20 mm Hg and of diastolic IAD > or =10 mm Hg. Thirty-one studies were identified. Most had methodological weaknesses; only four met the inclusion criteria. Pooled prevalences of the IAD from these four studies were 19.6% systolic > or =10 mm Hg (95% CI 18.0-21.3%), 4.2% systolic > or =20 mm Hg (95% CI 3.4-5.1%) and 8.1% diastolic > or =10 mm Hg (95%CI 6.9-9.2%). In conclusion, an IAD is present in a substantial number of patients and should be looked for whenever diagnosis and treatment depend on accurate measurements of BP. The importance of an IAD should be better emphasised in current hypertension management guidelines. There is evidence associating an IAD with peripheral vascular disease, raising the possibility that its presence may predict cardiovascular events.
Abstract.
Author URL.
2003
Clark CE (2003). Use of salmeterol/fluticasone combination (Seretide) in an asthma clinic: a pragmatic open study from primary care.
Primary Care Respiratory Journal,
12(3), 86-89.
Abstract:
Use of salmeterol/fluticasone combination (Seretide) in an asthma clinic: a pragmatic open study from primary care
Aims: the salmeterol/fluticasone combination inhaler (Seretide) has been shown to be effective in the management of asthma by randomised controlled trials. This study examined whether it was also effective in clinical use in primary care. Methods: Patients attending the surgery asthma clinic with persistent symptoms despite regular inhaled corticosteroid therapy were offered Seretide. Outcome measures were symptom scores, peak flow measurements, prescriptions for relief bronchodilators, mean daily inhaled steroid dosage, and asthma treatment costs. Patients were assessed at baseline, 9 and 19 months, comparing Seretide users with other asthma clinic attenders. Results: Fifty patients were studied, 20 started Seretide. Symptom scores at entry were higher for Seretide patients than the comparison group (total score 4.2 vs 1.5; p
Abstract.
2002
Clark CE, Powell RJ (2002). The differential blood pressure sign in general practice: prevalence and prognostic value.
FAMILY PRACTICE,
19(5), 439-441.
Author URL.
2001
Clark CE (2001). Difference in blood pressure between arms might reflect peripheral vascular disease [7]. British Medical Journal, 323(7309), 399-400.
2000
Clark CE, Coote JM, Silver DAT, Halpin DMG (2000). Asthma after childhood pneumonia - Reply.
BRITISH MEDICAL JOURNAL,
321(7271), 1290-1290.
Author URL.
Clark CE, Coote JM, Silver DAT, Halpin DMG (2000). Asthma after childhood pneumonia: six year follow up study.
BRITISH MEDICAL JOURNAL,
320(7248), 1514-1516.
Author URL.
1999
Clark CE, Bourne S (1999). Practice information on audiotape for visually-impaired patients.
BRITISH JOURNAL OF GENERAL PRACTICE,
49(438), 67-68.
Author URL.
Clark CE (1999). Time to go public on performance? [2]. British Journal of General Practice, 49(449).
1993
Clark CE, Ferguson AD, Siddorn JA (1993). Respiratory arrests in young asthmatics on salmeterol.
Respir Med,
87(3), 227-228.
Author URL.