The feasibility of a self-management programme (My Life After Stroke; MLAS) for stroke survivors

PURPOSE

An evidence-based, theory-driven self-management programme "My Life After Stroke" (MLAS) was developed to address the longer-term unmet needs of stroke survivors.This study's aim was to test the acceptability and feasibility of MLAS as well as exploring what outcomes measures to include as part of further testing.

METHODS

Stroke registers in four GP practices across Leicester and Cambridge were screened, invite letters sent to eligible stroke survivors and written, informed consent gained. Questionnaires including Southampton Stroke Self-Management Questionnaire (SSSMQ) were completed before and after MLAS.Participants (and carers) attended MLAS (consisting of two individual appointments and four group sessions) over nine weeks, delivered by two trained facilitators. Feedback was gained from participants (after the final group session and final individual appointment) and facilitators.

RESULTS

Seventeen of 36 interested stroke survivors participated alongside seven associated carers. 15/17 completed the programme and attendance ranged from 13-17 per session. A positive change of 3.5 of the SSSMQ was observed. Positive feedback was gained from facilitators and 14/15 participants recommended MLAS (one did not respond).

CONCLUSIONS

MLAS was a feasible self-management programme for stroke survivors and warrants further testing as part of the Improving Primary Care After Stroke (IPCAS) cluster randomised controlled trial.IMPLICATIONS FOR REHABILITATIONMy Life After Stroke is a self-management programme developed for stroke survivors living in the community.MLAS is feasible and acceptable to stroke survivors.MLAS could be considered to help address the unmet educational and psychological needs of stroke survivors.

Characteristics and health status of patients with and without confirmed HFpEF

Aims

Patients with heart failure with preserved ejection fraction (HFpEF) are usually older and multi-morbid and diagnosis can be challenging. The aims of this cohort study were to confirm diagnosis of HFpEF in patients with possible HFpEF recruited from primary care, to compare characteristics and health status between those with and without HFpEF, and to determine factors associated with health status in patients with HFpEF.

Methods

Patients with presumed HFpEF were recruited from primary care practices and underwent clinical assessment and diagnostic evaluation as part of a longitudinal cohort study. Health status was measured by Montreal Cognitive Assessment (MOCA), 6-minute walk test, symptoms, and the Kansas City Cardiomyopathy Questionnaire (KCCQ), and quality of life (QoL) by EQ-5D-5L visual analogue scale (VAS).

Results

151 patients (mean age 78.5±8.6 years, 40% women, mean EF 56% + 9.4) were recruited and 93 (61.6%) were confirmed HFpEF (those without HFpEF had other HF and cardiac diagnoses). Patients with and without HFpEF did not differ by age, MOCA, blood pressure, heart rate, NYHA class, proportion with atrial fibrillation, Charlson Comorbidity Index, or NT-ProBNP levels. Patients with HFpEF were more likely to be women, overweight or obese, frail, and to be more functionally impaired by 6 minute walk distance and gait speed than those without. Although not statistically significant, patients with HFpEF had clinically significant differences (>5 points) on the physical limitations, symptom burden and clinical summary subscales of the KCCQ, but did not differ by other subscales or by EQ-5D-5L VAS (70±17 vs 73±19, p=0.385). More patients with HFpEF reported daytime dyspnoea (63% vs 46%, p=0.035) and fatigue (81% vs 61%, p=0.008), but not other symptoms compared to those without HFpEF. For both groups BMI was moderately negatively correlated with KCCQ subscale scores, and 6 minute walk distance was positively correlated with KCCQ subscales.

Conclusions

Nearly 40% were not confirmed as HFpEF indicating the challenges of diagnosis. Patients with confirmed HFpEF differed by sex, overweight/obesity, frailty, functional impairment, and symptoms but not by age or comorbidities from those without HFpEF. These differences were reflected in some subscale scores of the KCCQ, but not how patients reported their quality of life on the KCCQ QoL subscale and EQ-5D-5L VAS. Older patients with HFpEF reported relatively high QoL despite poor health status by functional impairment, frailty and symptoms.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Institute of Health Research School of Primary Care Research

Self-monitoring of Blood Pressure in Patients With Hypertension-Related Multi-morbidity: Systematic Review and Individual Patient Data Meta-analysis

BACKGROUND

Studies have shown that self-monitoring of blood pressure (BP) is effective when combined with co-interventions, but its efficacy varies in the presence of some co-morbidities. This study examined whether self-monitoring can reduce clinic BP in patients with hypertension-related co-morbidity.

METHODS

A systematic review was conducted of articles published in Medline, Embase, and the Cochrane Library up to January 2018. Randomized controlled trials of self-monitoring of BP were selected and individual patient data (IPD) were requested. Contributing studies were prospectively categorized by whether they examined a low/high-intensity co-intervention. Change in BP and likelihood of uncontrolled BP at 12 months were examined according to number and type of hypertension-related co-morbidity in a one-stage IPD meta-analysis.

RESULTS

A total of 22 trials were eligible, 16 of which were able to provide IPD for the primary outcome, including 6,522 (89%) participants with follow-up data. Self-monitoring was associated with reduced clinic systolic BP compared to usual care at 12-month follow-up, regardless of the number of hypertension-related co-morbidities (−3.12 mm Hg, [95% confidence intervals −4.78, −1.46 mm Hg]; P value for interaction with number of morbidities = 0.260). Intense interventions were more effective than low-intensity interventions in patients with obesity (P < 0.001 for all outcomes), and possibly stroke (P < 0.004 for BP control outcome only), but this effect was not observed in patients with coronary heart disease, diabetes, or chronic kidney disease.

CONCLUSIONS

Self-monitoring lowers BP regardless of the number of hypertension-related co-morbidities, but may only be effective in conditions such obesity or stroke when combined with high-intensity co-interventions.

P2649Do these data apply to me? Examining the applicability of trials assessing strategies for optimal management of blood pressure to older patients in UK primary care

Background

There is debate as to what extent older patients (≥80 years) should be treated for high blood pressure. Existing trials show that blood pressure lowering in this population is effective at preventing stroke and heart failure but also results in an increased risk of adverse events. However, it has been suggested that these studies enrolled healthier patients, who are less representative of the general population and more likely to benefit from treatment.

Purpose

This study aimed to compare the characteristics of patients eligible for three blood pressure management trials and assess the likelihood of eligibility for each trial based on common characteristics of older patients.

Methods

Cross-sectional study of data extracted from the medical records of 15,376 patients aged ≥80 years, registered to 24 general practices in the south of England. Anonymised patient data relating to the eligibility criteria for two previous medication intensification trials (HYVET, SPRINT) and one medication reduction trial (OPTiMISE) were extracted. Patients eligible for each trial were defined according to criteria specified in each trial protocol. Descriptive statistics were used to define the characteristics of each trial population. A logistic regression model was constructed to estimate predictors of eligibility for each trial, with practice included as a random effect.

Results

Approximately 268 (1.7%), 5,290 (34.4%) and 3,940 (25.6%) patients were eligible for HYVET, SPRINT and OPTiMISE trials respectively. There was little overlap in eligibility for each trial (1.0% were eligible for HYVET and SPRINT; 0% were eligible for HYVET and OPTiMISE; 10.2% were eligible for SPRINT and OPTiMISE). Patients eligible for OPTiMISE were comparable to the general population in terms of frailty (eFI 0.12 [OPTiMISE] vs 0.11 [general population]), but had more morbidities (4 vs 3) and cardiovascular medications prescribed (4 vs 2). Patients in HYVET and SPRINT were less frail, multi-morbid and prescribed less cardiovascular medications. Overall, increasing frailty and a history of cardiovascular disease reduced the likelihood of being eligible for any trial.

Conclusions

Patients eligible for OPTiMISE appear to best represent the population aged ≥80 years attending UK primary care. Increasing frailty and/or multi-morbidity reduce the likelihood of eligibility for all three blood pressure trials. Caution should be exercised when applying the results from randomised controlled trials to management of blood pressure in frail and multi-morbid patients.

Acknowledgement/Funding

This study was funded by the National Institute for Health Research (NIHR) SPCR and Oxford CLAHRC

Perceptions of self-rated health among stroke survivors: a qualitative study in the United Kingdom

Background

Self-rated health predicts health outcomes independently of levels of disability or mood. Little is known about what influences the subjective health experience of stroke survivors. Our aim was to investigate stroke survivors’ perceptions of self-rated health, with the intention of informing the design of interventions that may improve their subjective health experience.

Methods

We conducted semi-structured interviews with a purposive sample of 28 stroke survivors recruited from a stroke unit and follow-up outpatient clinic, 4–6 months after stroke, to explore what factors are perceived to be part of self-rated health in the early stages of recovery. Qualitative data were analysed using a thematic analysis approach to identify underlying themes.

Results

Participants’ accounts show that stroke survivors’ perceptions of self-rated health are multifactorial, comprising physical, psychological and social components. Views on future recovery after stroke play a role in present health experience and are shaped by psychosocial resources that are influenced by past experiences of ill-health, dispositional outlook such as degree of optimism, a sense of control and views on ageing.

Conclusions

Severity of physical limitations alone does not influence perceptions of self-rated health among stroke survivors. Self-rated health in stroke survivors is a multidimensional construct shaped by changes in health status occurring after the stroke, individual characteristics and social context. Understanding the factors stroke survivors themselves associate with better health will inform the development of effective approaches to improve rehabilitation and recovery after stroke.

Screening for Atrial Fibrillation

Approximately 10% of ischemic strokes are associated with atrial fibrillation (AF) first diagnosed at the time of stroke. Detecting asymptomatic AF would provide an opportunity to prevent these strokes by instituting appropriate anticoagulation. The AF-SCREEN international collaboration was formed in September 2015 to promote discussion and research about AF screening as a strategy to reduce stroke and death and to provide advocacy for implementation of country-specific AF screening programs. During 2016, 60 expert members of AF-SCREEN, including physicians, nurses, allied health professionals, health economists, and patient advocates, were invited to prepare sections of a draft document. In August 2016, 51 members met in Rome to discuss the draft document and consider the key points arising from it using a Delphi process. These key points emphasize that screen-detected AF found at a single timepoint or by intermittent ECG recordings over 2 weeks is not a benign condition and, with additional stroke factors, carries sufficient risk of stroke to justify consideration of anticoagulation. With regard to the methods of mass screening, handheld ECG devices have the advantage of providing a verifiable ECG trace that guidelines require for AF diagnosis and would therefore be preferred as screening tools. Certain patient groups, such as those with recent embolic stroke of uncertain source (ESUS), require more intensive monitoring for AF. Settings for screening include various venues in both the community and the clinic, but they must be linked to a pathway for appropriate diagnosis and management for screening to be effective. It is recognized that health resources vary widely between countries and health systems, so the setting for AF screening should be both country- and health system-specific. Based on current knowledge, this white paper provides a strong case for AF screening now while recognizing that large randomized outcomes studies would be helpful to strengthen the evidence base.

Primary care REFerral for EchocaRdiogram (REFER) in heart failure: a diagnostic accuracy study

BACKGROUND

Symptoms of breathlessness, fatigue, and ankle swelling are common in general practice but deciding which patients are likely to have heart failure is challenging.

AIM

To evaluate the performance of a clinical decision rule (CDR), with or without N-Terminal pro-B type natriuretic peptide (NT-proBNP) assay, for identifying heart failure.

DESIGN AND SETTING

Prospective, observational, diagnostic validation study of patients aged >55 years, presenting with shortness of breath, lethargy, or ankle oedema, from 28 general practices in England.

METHOD

The outcome was test performance of the CDR and natriuretic peptide test in determining a diagnosis of heart failure. The reference standard was an expert consensus panel of three cardiologists.

RESULTS

Three hundred and four participants were recruited, with 104 (34.2%; 95% confidence interval [CI] = 28.9 to 39.8) having a confirmed diagnosis of heart failure. The CDR+NT-proBNP had a sensitivity of 90.4% (95% CI = 83.0 to 95.3) and specificity 45.5% (95% CI = 38.5 to 52.7). NT-proBNP level alone with a cut-off <400 pg/ml had sensitivity 76.9% (95% CI = 67.6 to 84.6) and specificity 91.5% (95% CI = 86.7 to 95.0). At the lower cut-off of NT-proBNP <125 pg/ml, sensitivity was 94.2% (95% CI = 87.9 to 97.9) and specificity 49.0% (95% CI = 41.9 to 56.1).

CONCLUSION

At the low threshold of NT-proBNP <125 pg/ml, natriuretic peptide testing alone was better than a validated CDR+NT-proBNP in determining which patients presenting with symptoms went on to have a diagnosis of heart failure. The higher NT-proBNP threshold of 400 pg/ml may mean more than one in five patients with heart failure are not appropriately referred. Guideline natriuretic peptide thresholds may need to be revised.

Prevalence and predictors of hospital prealerting in acute stroke: a mixed methods study

Background

Thrombolysis can significantly reduce the burden of stroke but the time window for safe and effective treatment is short. In patients travelling to hospital via ambulance, the sending of a ‘prealert’ message can significantly improve the timeliness of treatment.

Objective

Examine the prevalence of hospital prealerting, the extent to which prealert protocols are followed and what factors influence emergency medical services (EMS) staff's decision to send a prealert.

Methods

Cohort study of patients admitted to two acute stroke units in West Midlands (UK) hospitals using linked data from hospital and EMS records. A logistic regression model examined the association between prealert eligibility and whether a prealert message was sent. In semistructured interviews, EMS staff were asked about their experiences of patients with suspected stroke.

Results

Of the 539 patients eligible for this study, 271 (51%) were recruited. Of these, only 79 (29%) were eligible for prealerting according to criteria set out in local protocols but 143 (53%) were prealerted. Increasing number of Face, Arm, Speech Test symptoms (1 symptom, OR 6.14, 95% CI 2.06 to 18.30, p=0.001; 2 symptoms, OR 31.36, 95% CI 9.91 to 99.24, p<0.001; 3 symptoms, OR 75.84, 95% CI 24.68 to 233.03, p<0.001) and EMS contact within 5 h of symptom onset (OR 2.99, 95% CI 1.37 to 6.50 p=0.006) were key predictors of prealerting but eligibility for prealert as a whole was not (OR 1.92, 95% CI 0.85 to 4.34 p=0.12). In qualitative interviews, EMS staff displayed varying understanding of prealert protocols and described frustration when their interpretation of the prealert criteria was not shared by ED staff.

Conclusions

Up to half of the patients presenting with suspected stroke in this study were prealerted by EMS staff, regardless of eligibility, resulting in disagreements with ED staff during handover. Aligning the expectations of EMS and ED staff, perhaps through simplified prealert protocols, could be considered to facilitate more appropriate use of hospital prealerting in acute stroke.

Understanding stroke survivors' and informal carers' experiences of and need for primary care and community health services--a systematic review of the qualitative literature: protocol

INTRODUCTION

Despite the rising prevalence of stroke, no comprehensive model of postacute stroke care exists. Research on stroke has focused on acute care and early supported discharge, with less attention dedicated to longer term support in the community. Likewise, relatively little research has focused on long-term support for informal carers. This review aims to synthesise and appraise extant qualitative evidence on: (1) long-term healthcare needs of stroke survivors and informal carers, and (2) their experiences of primary care and community health services. The review will inform the development of a primary care model for stroke survivors and informal carers.

METHODS AND ANALYSIS

We will systematically search 4 databases: MEDLINE, EMBASE, PsycINFO and CINAHL for published qualitative evidence on the needs and experiences of stroke survivors and informal carers of postacute care delivered by primary care and community health services. Additional searches of reference lists and citation indices will be conducted. The quality of articles will be assessed by 2 independent reviewers using a Critical Appraisal Skills Programme (CASP) checklist. Disagreements will be resolved through discussion or third party adjudication. Meta-ethnography will be used to synthesise the literature based on first-order, second-order and third-order constructs. We will construct a theoretical model of stroke survivors' and informal carers' experiences of primary care and community health services.

ETHICS AND DISSEMINATION

The results of the systematic review will be disseminated via publication in a peer-reviewed journal and presented at a relevant conference. The study does not require ethical approval as no patient identifiable data will be used.

Key innovation or adaptive change? A test of leaf traits using Triodiinae in Australia

The evolution of novel traits ("key innovations") allows some lineages to move into new environments or adapt to changing climates, whereas other lineages may track suitable habitat or go extinct. We test whether, and how, trait shifts are linked to environmental change using Triodiinae, C4 grasses that form the dominant understory over about 30% of Australia. Using phylogenetic and relaxed molecular clock estimates, we assess the Australian biogeographic origins of Triodiinae and reconstruct the evolution of stomatal and vascular bundle positioning. Triodiinae diversified from the mid-Miocene, coincident with the aridification of Australia. Subsequent niche shifts have been mostly from the Eremaean biome to the savannah, coincident with the expansion of the latter. Biome shifts are correlated with changes in leaf anatomy and radiations within Triodiinae are largely regional. Symplectrodia and Monodia are nested within Triodia. Rather than enabling biome shifts, convergent changes in leaf anatomy have probably occurred after taxa moved into the savannah biome-they are likely to have been subsequent adaptions rather than key innovations. Our study highlights the importance of testing the timing and origin of traits assumed to be phenotypic innovations that enabled ecological shifts.

Potential impact of new oral anticoagulants on the management of atrial fibrillation-related stroke in primary care

AIM

Anticoagulant prophylaxis with vitamin K antagonists (such as warfarin) is effective in reducing the risk of stroke in patients with atrial fibrillation (AF). New oral anticoagulants have emerged as potential alternatives to traditional oral agents. The purpose of this review was to summarise the effectiveness and safety of rivaroxaban, dabigatran and apixaban in stroke prevention in patients with AF in phase III trials, evaluate their cost-effectiveness and consider the implications for primary care.

METHODOLOGY

A literature search was performed between 2007 and 2012, selecting all phase III trials (ROCKET AF, RE-LY and ARISTOTLE) of new oral anticoagulants and relevant cost-benefit studies.

RESULTS

Evidence shows that all three agents are at least as effective as warfarin in the prevention of stroke and systemic emboli, with similar safety profiles. Cost-benefit studies of rivaroxaban and dabigatran further confirm their potential use as alternatives to warfarin in clinical practice. These observations may allow stratification of the general practice AF population, to help prioritise which patients may benefit from receiving a new oral anticoagulant.

CONCLUSION

The clinical and economic benefits of the new oral anticoagulants, along with appropriate risk stratification, may enable a higher number of patients with AF to receive effective and convenient prophylaxis for stroke prevention.

How can we best detect atrial fibrillation?

Atrial fibrillation (AF) is an arrhythmia of increasing prevalence associated with a reducible risk of stroke. We conducted a systematic review to address five questions relating to how we can best detect AF: 1. Are there useful screening tests to determine who should have a 12-lead electrocardiogram (ECG)? Potential screening tests, all with acceptable sensitivity, include pulse palpation, single-lead ECG and newer technologies such as modified sphygmomanometers or a finger probe device. Pulse palpation has a high number of false positives, but is the cheapest method. 2. Is it more effective to offer 12-lead ECGs to the whole population (or specific sub-groups) or only to those who screen positive for AF? The cost-effectiveness of new devices, such as a modified blood pressure monitor, needs to be assessed. It is more cost-effective to opportunistically screen people rather than to offer a 12-lead ECG to everybody. 3. How accurate are different healthcare professionals and interpretative software at diagnosing AF on ECG? Definitive diagnosis of AF should be by 12-lead ECG, interpreted by someone with appropriate expertise. Computer software is not currently sensitive enough to be used alone to diagnose AF on ECG. Primary care practitioners may not accurately detect AF on ECG, but consistently high accuracy can be achieved by healthcare professionals with adequate training. 4. How best can we diagnose paroxysmal atrial fibrillation (PAF)? In patients in whom PAF is suspected, longer periods of monitoring will detect more cases of PAF. 5. What is the impact of the use of different ECG monitoring strategies (e.g. Holter monitoring, serial ECGs, continuous ECG) on AF detection rates post-stroke? In patients post-stroke, a single ECG will miss cases of PAF which can be detected by longer duration monitoring such as Holter monitoring, cardiac event recorders and serial ECGs. Further research into the cost-effectiveness of these methods, the duration of monitoring required and the clinical significance of the PAF detected is needed.

Impact of age and sex on primary preventive treatment for cardiovascular disease in the West Midlands, UK: cross sectional study

OBJECTIVES

To establish the impact of age and sex on primary preventive treatment for cardiovascular disease in a typical primary care population.

DESIGN

Cross sectional study of anonymised patient records.

PARTICIPANTS

All 41,250 records of patients aged ≥ 40 registered at 19 general practices in the West Midlands, United Kingdom, were extracted and analysed.

MAIN OUTCOME MEASURES

Patients' demographics, risk factors for cardiovascular disease (blood pressure, total cholesterol concentration), and prescriptions for primary preventive drugs were extracted from patients' records. Patients were subdivided into five year age bands up to 85 (patients aged ≥ 85 were analysed as one group) and prescribing trends across the population were assessed by estimating the proportion of patients prescribed with antihypertensive drug or statin drug, or both, in each group.

RESULTS

Of the 41,250 records screened in this study, 36,679 (89%) patients did not have a history of cardiovascular disease and therefore could be considered for primary preventive treatment. The proportion receiving antihypertensive drugs increased with age (from 5% (378/6978) aged 40-44 to 57% (621/1092) aged ≥ 85) as did the proportion taking statins up to the age of 74 (from 3% (201/6978) aged 40-44 to 29% (675/2367) aged 70-74). In those aged 75 and above, the odds of a receiving prescription for a statin (relative to the 40-44 age group) decreased with every five year increment in age (odds ratio 12.9 (95% confidence interval 10.8 to 15.3) at age 75-79 to 5.7 (4.6 to 7.2) at age ≥ 85; P<0.001). There were no consistent differences in prescribing trends by sex.

CONCLUSIONS

Previously described undertreatment of women in secondary prevention of cardiovascular disease was not observed for primary prevention. Low use of statins in older people highlights the need for a stronger evidence base and clearer guidelines for people aged over 75.

Relative effectiveness of clinic and home blood pressure monitoring compared with ambulatory blood pressure monitoring in diagnosis of hypertension: systematic review

OBJECTIVE

To determine the relative accuracy of clinic measurements and home blood pressure monitoring compared with ambulatory blood pressure monitoring as a reference standard for the diagnosis of hypertension.

DESIGN

Systematic review with meta-analysis with hierarchical summary receiver operating characteristic models. Methodological quality was appraised, including evidence of validation of blood pressure measurement equipment.

DATA SOURCES

Medline (from 1966), Embase (from 1980), Cochrane Database of Systematic Reviews, DARE, Medion, ARIF, and TRIP up to May 2010. Eligibility criteria for selecting studies Eligible studies examined diagnosis of hypertension in adults of all ages using home and/or clinic blood pressure measurement compared with those made using ambulatory monitoring that clearly defined thresholds to diagnose hypertension.

RESULTS

The 20 eligible studies used various thresholds for the diagnosis of hypertension, and only seven studies (clinic) and three studies (home) could be directly compared with ambulatory monitoring. Compared with ambulatory monitoring thresholds of 135/85 mm Hg, clinic measurements over 140/90 mm Hg had mean sensitivity and specificity of 74.6% (95% confidence interval 60.7% to 84.8%) and 74.6% (47.9% to 90.4%), respectively, whereas home measurements over 135/85 mm Hg had mean sensitivity and specificity of 85.7% (78.0% to 91.0%) and 62.4% (48.0% to 75.0%).

CONCLUSIONS

Neither clinic nor home measurement had sufficient sensitivity or specificity to be recommended as a single diagnostic test. If ambulatory monitoring is taken as the reference standard, then treatment decisions based on clinic or home blood pressure alone might result in substantial overdiagnosis. Ambulatory monitoring before the start of lifelong drug treatment might lead to more appropriate targeting of treatment, particularly around the diagnostic threshold.

Performance of stroke risk scores in older people with atrial fibrillation not taking warfarin: comparative cohort study from BAFTA trial

OBJECTIVE

To compare the predictive power of the main existing and recently proposed schemes for stratification of risk of stroke in older patients with atrial fibrillation.

DESIGN

Comparative cohort study of eight risk stratification scores.

SETTING

Trial of thromboprophylaxis in stroke, the Birmingham Atrial Fibrillation in the Aged (BAFTA) trial.

PARTICIPANTS

665 patients aged 75 or over with atrial fibrillation based in the community who were randomised to the BAFTA trial and were not taking warfarin throughout or for part of the study period.

MAIN OUTCOME MEASURES

Events rates of stroke and thromboembolism.

RESULTS

54 (8%) patients had an ischaemic stroke, four (0.6%) had a systemic embolism, and 13 (2%) had a transient ischaemic attack. The distribution of patients classified into the three risk categories (low, moderate, high) was similar across three of the risk stratification scores (revised CHADS(2), NICE, ACC/AHA/ESC), with most patients categorised as high risk (65-69%, n = 460-457) and the remaining classified as moderate risk. The original CHADS(2) (Congestive heart failure, Hypertension, Age ≥ 75 years, Diabetes, previous Stroke) score identified the lowest number as high risk (27%, n = 180). The incremental risk scores of CHADS(2), Rietbrock modified CHADS(2), and CHA(2)DS(2)-VASc (CHA(2)DS(2)-Vascular disease, Age 65-74 years, Sex) failed to show an increase in risk at the upper range of scores. The predictive accuracy was similar across the tested schemes with C statistic ranging from 0.55 (original CHADS(2)) to 0.62 (Rietbrock modified CHADS(2)), with all except the original CHADS(2) predicting better than chance. Bootstrapped paired comparisons provided no evidence of significant differences between the discriminatory ability of the schemes.

CONCLUSIONS

Based on this single trial population, current risk stratification schemes in older people with atrial fibrillation have only limited ability to predict the risk of stroke. Given the systematic undertreatment of older people with anticoagulation, and the relative safety of warfarin versus aspirin in those aged over 70, there could be a pragmatic rationale for classifying all patients over 75 as "high risk" until better tools are available.

Impact of study design on recruitment of patients to a primary care trial: an observational time series analysis of the Birmingham Atrial Fibrillation Treatment of the Aged (BAFTA) study

BACKGROUND

recruitment targets to randomized controlled trials (RCTs) are often not met. Many interventions are used to improve recruitment but there is little empirical evidence on whether these approaches work.

OBJECTIVE

to examine whether changes to the design and conduct of a primary care-based RCT were associated with changes in patient recruitment.

METHODS

an observational time series analysis of recruitment to a primary care-based multi-centre RCT of aspirin versus warfarin for stroke prevention, which involved 330 practices. Several changes to the trial protocol and procedures were made over the 4 years of patient recruitment. For each quarter throughout the recruitment period, the recruitment rate per 1000 total population in active practices was calculated.

RESULTS

the recruitment target of 930 patients was exceeded. Fluctuations in recruitment rate occurred during the recruitment period. Following protocol changes aimed to reduce clinical workload, there was a significant increase in recruitment during the final 6 months of the study, during a period when there was not a similarly large increase in the total population available.

CONCLUSIONS

these findings suggest that the conduct of a trial is an important consideration if studies are to recruit successfully. Expanding the number of centres may not be the most effective way to improve recruitment.

Primary care research and clinical practice: cardiovascular disease

Improvement in survival of patients with cardiovascular diseases and an ageing population mean that management of cardiovascular conditions remains an important challenge for primary care. Traditionally cardiovascular research has been based largely in secondary or tertiary care settings. The majority of care for people with cardiovascular diseases, however, takes place in the community and within primary care. In recent years, progress has been made in conducting cardiovascular research within primary care itself. A number of different methodologies including large prospective cohort studies, randomised controlled trials, and qualitative designs have been used to inform optimal cardiovascular disease management for those in the community. Some of the recent research evidence in primary care in three areas of cardiovascular medicine--atrial fibrillation, heart failure, and cardiovascular risk prediction and management--are discussed in this review. These seek to demonstrate the contribution made by primary care research to the management of cardiovascular diseases.

Systematic review and individual patient data meta-analysis of diagnosis of heart failure, with modelling of implications of different diagnostic strategies in primary care

OBJECTIVES

To assess the accuracy in diagnosing heart failure of clinical features and potential primary care investigations, and to perform a decision analysis to test the impact of plausible diagnostic strategies on costs and diagnostic yield in the UK health-care setting.

DATA SOURCES

MEDLINE and CINAHL were searched from inception to 7 July 2006. 'Grey literature' databases and conference proceedings were searched and authors of relevant studies contacted for data that could not be extracted from the published papers.

REVIEW METHODS

A systematic review of the clinical evidence was carried out according to standard methods. Individual patient data (IPD) analysis was performed on nine studies, and a logistic regression model to predict heart failure was developed on one of the data sets and validated on the other data sets. Cost-effectiveness modelling was based on a decision tree that compared different plausible investigation strategies.

RESULTS

Dyspnoea was the only symptom or sign with high sensitivity (89%), but it had poor specificity (51%). Clinical features with relatively high specificity included history of myocardial infarction (89%), orthopnoea (89%), oedema (72%), elevated jugular venous pressure (70%), cardiomegaly (85%), added heart sounds (99%), lung crepitations (81%) and hepatomegaly (97%). However, the sensitivity of these features was low, ranging from 11% (added heart sounds) to 53% (oedema). Electrocardiography (ECG), B-type natriuretic peptides (BNP) and N-terminal pro-B-type natriuretic peptides (NT-proBNP) all had high sensitivities (89%, 93% and 93% respectively). Chest X-ray was moderately specific (76-83%) but insensitive (67-68%). BNP was more accurate than ECG, with a relative diagnostic odds ratio of ECG/BNP of 0.32 (95% CI 0.12-0.87). There was no difference between the diagnostic accuracy of BNP and NT-proBNP. A model based upon simple clinical features and BNP derived from one data set was found to have good validity when applied to other data sets. A model substituting ECG for BNP was less predictive. From this a simple clinical rule was developed: in a patient presenting with symptoms such as breathlessness in whom heart failure is suspected, refer directly to echocardiography if the patient has a history of myocardial infarction or basal crepitations or is a male with ankle oedema; otherwise, carry out a BNP test and refer for echocardiography depending on the results of the test. On the basis of the cost-effectiveness analysis carried out, such a decision rule is likely to be considered cost-effective to the NHS in terms of cost per additional case detected. The cost-effectiveness analysis further suggested that, if likely benefit to the patient in terms of improved life expectancy is taken into account, the optimum strategy would be to refer all patients with symptoms suggestive of heart failure directly for echocardiography.

CONCLUSIONS

The analysis suggests the need for important changes to the NICE recommendations. First, BNP (or NT-proBNP) should be recommended over ECG and, second, some patients should be referred straight for echocardiography without undergoing any preliminary investigation. Future work should include evaluation of the clinical rule described above in clinical practice.

A before and after study of the impact of Specialist Workers for Older People

BACKGROUND

Case management of vulnerable older people by Community Matrons has been introduced into the UK. A locally designed case management approach, The Specialist Workers for Older People (SWOP) Service, was implemented by a Central England Primary Care Trust. Here we report an evaluation of this service.

METHODS

Before and after study of 418 people (207 before; 211 after) aged > or =75 at high risk of emergency hospital admission. SWOPs carry out assessments of social and medical needs, produce individual care plans, coordinate care and refer to appropriate agencies. Univariable analysis was used to determine the association of SWOPs on changes in hospital admission rates and primary care workload.

RESULTS

There was a non-significant reduction in hospital admissions from 0.91 to 0.67 per patient. There was a significant increase in routine GP surgery visits, from an average 1.3 to 2.6 per patient. The number of emergency home visits decreased from an average 2.8 to 1.1 per patient (P < 0.001).

CONCLUSIONS

Case management might reduce hospital admissions and is potentially a cost-effective service. However, not all case management schemes are successful. With the introduction of Community Matrons, it is important to understand what elements of the SWOP service contributed to its success.

A before and after study of the impact of Specialist Workers for Older People

BACKGROUND

Case management of vulnerable older people by Community Matrons has been introduced into the UK. A locally designed case management approach, the Specialist Workers for Older People (SWOP) Service, was implemented by a Central England Primary Care Trust. Here, we report an evaluation of this service.

METHODS

Before and after study of 418 people (207 before; 211 after) aged >or=75 at high risk of emergency hospital admission. SWOPs carry out assessments of social and medical needs, produce individual care plans, co-ordinate care and refer to appropriate agencies. Univariable analysis was used to determine the association of SWOPs on changes in hospital admission rates and primary care workload.

RESULTS

There was a non-significant reduction in hospital admissions from 0.91 to 0.67 per patient. There was a significant increase in routine general practitioner surgery visits, from an average 1.3 to 2.6 per patient. The number of emergency home visits decreased from an average 2.8 to 1.1 per patient (P < 0.001).

CONCLUSIONS

Case management might reduce hospital admissions and is potentially a cost-effective service. However, not all case management schemes are successful. With the introduction of Community Matrons, it is important to understand what elements of the SWOP service contributed to its success.

The Birmingham Rehabilitation Uptake Maximisation study (BRUM): a randomised controlled trial comparing home-based with centre-based cardiac rehabilitation

OBJECTIVE

To compare the outcomes of home-based (using the Heart Manual) and centre-based cardiac rehabilitation programmes.

DESIGN

Randomised controlled trial and parallel economic evaluation.

SETTING

Predominantly inner-city, multi-ethnic population in the West Midlands, England.

PATIENTS

525 patients referred to four hospitals for cardiac rehabilitation following myocardial infarction or coronary revascularisation.

INTERVENTIONS

A home-based cardiac rehabilitation programme compared with centre-based programmes.

MAIN OUTCOME MEASURES

Smoking cessation, blood pressure (systolic blood pressure (SBP), diastolic blood pressure (DBP)), total cholesterol (TC) and high-density lipoprotein (HDL)-cholesterol, psychological status (HADS anxiety and depression) and exercise capacity (incremental shuttle walking test, ISWT) measured at 12 months. Health service resource use, quality of life utility and costs were quantified.

RESULTS

There were no significant differences in the main outcomes when the home-based was compared with the centre-based programme at 12 months. Adjusted mean difference (95% CI) for SBP was 1.94 mm Hg (-1.1 to 5.0); DBP 0.42 mm Hg (-1.25 to 2.1); TC 0.1 mmol/l (-0.05 to 0.24); HADS anxiety -0.02 (-0.69 to 0.65); HADS depression -0.35 (-0.95 to 0.25); distance on ISWT -21.5 m (-48.3 to 5.2). The relative risk of being a smoker in the home arm was 0.90. The cost per patient to the NHS was significantly higher in the home arm at 198 pounds, (95% CI 189 to 208) compared to 157 pounds (95% CI 139 to 175) in the centre-based arm. However when the patients' cost of travel was included, these differences were no longer significant. Conclusions A home-based cardiac rehabilitation programme does not produce inferior outcomes when compared to traditional centre-based programmes as provided in the United Kingdom.

The Birmingham Rehabilitation Uptake Maximisation Study (BRUM). Home-based compared with hospital-based cardiac rehabilitation in a multi-ethnic population: cost-effectiveness and patient adherence

OBJECTIVES

To evaluate the relative effectiveness and cost-effectiveness of a home-based programme of cardiac rehabilitation using the Heart Manual, with centre-based programmes. It also sought to explore the reasons for non-adherence to cardiac rehabilitation programmes.

DESIGN

An individually randomised trial, with minimisation for age, gender, ethnicity, initial diagnosis and hospital of recruitment. Participants were followed up after 6, 12 and 24 months by questionnaire and clinical assessment. Individual semistructured interviews were undertaken in the homes of a purposive sample of patients who did not adhere to their allocated programme, and focus groups were undertaken with groups of patients who adhered to the programmes.

SETTING

Four hospitals in predominantly inner-city, multi-ethnic, socio-economically deprived areas of the West Midlands in England, for 2 years from 1 February 2002.

PARTICIPANTS

A total of 525 patients who had experienced a myocardial infarction (MI) or coronary revascularisation within the previous 12 weeks.

INTERVENTIONS

All the rehabilitation programmes included exercise, relaxation, education and lifestyle counselling. All patients were seen by a cardiac rehabilitation nurse prior to hospital discharge and provided with information about their condition and counselling about risk factor modification. The four centre-based programmes varied in length from nine sessions at weekly intervals of education, relaxation and circuit training to 24 individualised sessions over 12 weeks of mainly walking, fixed cycling and rowing with group-based education. The home-based programme consisted of an appropriate version of the Heart Manual, home visits and telephone contact. The Heart Manual was introduced to patients on an individual basis, either in hospital or on a home visit. Home visits by a nurse took place at approximately 1, 6 and 12 weeks after recruitment, with a telephone call at 3 weeks. At the final visit, patients were encouraged to maintain their lifestyle changes and to continue with their exercise programme. Where needed, follow-up was made by a rehabilitation nurse who spoke Punjabi. An audiotape of an abridged version of the Heart Manual in Punjabi accompanied the manual for patients with a limited command of English.

MAIN OUTCOME MEASURES

Primary outcomes were smoking cessation, blood pressure, total and high-density lipoprotein cholesterol, exercise capacity measured by the incremental shuttle walking test and psychological status measured by the Hospital Anxiety and Depression Scale (HADS). Secondary outcomes included self-reported diet, physical activity, cardiac symptoms and quality of life. Health service resource use and costs of rehabilitation programmes from health service and societal perspectives were also measured. Adherence to the physical activity element of the rehabilitation programmes was measured by questionnaire 6, 9 and 12 weeks.

RESULTS

No clinically or statistically significant differences were found in any of the primary or secondary outcome measures between the home- and centre-based groups. Significant improvements in total cholesterol, smoking prevalence, the HADS anxiety score, self-reported physical activity and diet were seen in both arms between baseline and the 6-month follow-up. Five or more contacts with a cardiac rehabilitation nurse were received by 96% of home-based participants, whereas only 56% of centre-based participants attended this many rehabilitation classes. The direct rehabilitation costs to the health service were significantly higher for the home-based programme (mean cost 198 pounds versus 157 pounds for the centre-based programme), but when patient costs were included the mean cost of the centre-based arm rose to 182 pounds. Patients' reasons for not taking up or adhering to cardiac rehabilitation were multifactorial and very individual. Other health problems limited some patients' ability to exercise. Most non-adherers found some aspects of their cardiac rehabilitation programme helpful. Many had adapted advice on rehabilitation and were continuing to exercise in other ways and had made lifestyle changes, particularly to their diet. The home-based patients' lack of motivation to exercise on their own at home was a major factor in non-adherence. The focus groups revealed little diversity of views among patients from each programme. Patients in the hospital programme enjoyed the camaraderie of group exercise and the home-based patients valued the wealth of information and advice in the Heart Manual.

CONCLUSIONS

A home-based cardiac rehabilitation programme for low- to moderate-risk patients does not produce inferior outcomes compared with the traditional centre-based programmes. With the level of home visiting in this trial, the home-based programme was more costly to the health service, but with the difference in costs borne by patients attending centre-based programmes. Different reasons were given by home and hospital cardiac rehabilitation patients for not taking up or adhering to cardiac rehabilitation, with home-based patients often citing a lack of motivation to exercise at home. Social characteristics, individual patient needs and the location of cardiac rehabilitation programmes need to be taken into account in programme design to maximise participation. Research is recommended into cardiac rehabilitation in patients from ethnic minority groups; measurement tools to assess physical activity and dietary change; evaluating the Heart Manual in patients who decline centre-based cardiac rehabilitation; the implementation of home-based programmes in the UK; and strategies that sustain physical activity in the long term.

What do stroke patients and their carers want from community services?

BACKGROUND

Previous research has focused on the longer term needs of 'new' stroke patients at fixed time intervals after the event, but neglected those of stroke patients who may have had the event many years earlier.

OBJECTIVE

To identify the long-term support needs of patients with prevalent stroke, and their carers identified from practice stroke registers.

DESIGN OF STUDY

Patients and their carers were invited to attend focus groups at the university, a nursing home or in the community.

SETTING

Seven practices in South Birmingham. Adults (18+) with a validated record of stroke.

METHODS

Focus groups were audio-taped and data analysed using a constant comparison method.

RESULTS

Twenty-seven patients and six carers participated in the study. Three major themes emerged: emotional and psychological problems; lack of information available for patients and their families; the importance of Primary Care as the first point of contact for information or problems, even if these were non medical.

CONCLUSIONS

Better methods of providing information for long-term survivors of stroke, and for addressing their emotional and psychological needs are required. Primary care could be a key setting for helping to provide more inclusive services for both patient and carer.

A randomised controlled trial and cost-effectiveness study of systematic screening (targeted and total population screening) versus routine practice for the detection of atrial fibrillation in people aged 65 and over. The SAFE study

OBJECTIVES

To determine the most cost-effective method of screening for atrial fibrillation (AF) in the population aged 65 years and over, as well as its prevalence and incidence in this age group. Also to evaluate the relative cost-effectiveness of different methods of recording and interpreting the electrocardiogram (ECG) within a screening programme.

DESIGN

Multicentred randomised controlled trial. Purposefully selected general practices were randomly allocated to 25 intervention practices and 25 control practices.

SETTING

Fifty primary care centres across the West Midlands, UK.

PARTICIPANTS

Patients aged 65 years and over.

INTERVENTIONS

GPs and practice nurses in the intervention practices received education on the importance of AF detection and ECG interpretation. Patients in the intervention practices were randomly allocated to systematic (n = 5000) or opportunistic screening (n = 5000). Prospective identification of pre-existing risk factors for AF within the screened population enabled comparison between targeted screening of people at higher risk of AF and total population screening.

MAIN OUTCOME MEASURES

AF detection rates in systematically screened and opportunistically screened populations in the intervention practices were compared with AF detection rate in 5000 patients in the control practices. The screening period was 12 months.

RESULTS

Baseline prevalence of AF was 7.2%, with a higher prevalence in males (7.8%) and patients aged 75 years and over (10.3%). The control population demonstrated higher baseline prevalence (7.9%) than either the systematic (6.9%) or opportunistic (6.9%) intervention population. In the control population 47 new cases were detected (incidence 1.04% per year). In the opportunistic arm 243 patients without a baseline diagnosis of AF were found to have an irregular pulse, with 177 having an ECG, yielding 31 new cases (incidence 0.69% per year). A further 44 cases were detected outside the screening programme (overall incidence 1.64% per year). In the systematic arm 2357 patients had an ECG yielding 52 new cases (incidence 1.1% per year). Of these, 31 were detected by targeted screening and a further 21 by total population screening. A further 22 cases were detected outside the screening programme (overall incidence 1.62% per year). In terms of ECG interpretation, computerised decision support software (CDSS) gave a sensitivity of 87.3%, a specificity of 99.1% and a positive predictive value (PPV) of 89.5% compared with the gold standard (cardiologist reporting). GPs and practice nurses performed less well. The only difference in performance between intervention populations and controls was that practice nurses from the control arm performed less well than with intervention practice nurses on interpretation of limb-lead (PPV 38.8% versus 20.8%) and single-lead (PPV 37.7% versus 24.0%) ECGs. The within-trial economic evaluation results showed the lowest incremental cost to be for the opportunistic arm, with an incremental cost-effectiveness ratio of 337 pounds Sterling for each additional case detected compared to the control arm. Opportunistic screening dominated both more intensive screening strategies. Model-based analyses showed small differences in cost and quality-adjusted life-years for different methods and intensities of screening, but annual opportunistic screening resulted in the lowest number of ischaemic strokes and greatest proportion of cases of AF diagnosed. Probabilistic sensitivity results indicated that there was a probability of approximately 60% that screening from the age of 65 years was cost-effective in both men and women.

CONCLUSIONS

The results of the study indicated that in terms of a screening programme for atrial fibrillation in patients 65 and over, the only strategy that improved on routine practice was opportunistic screening, model-based analyses indicated that there was a probability of approximately 60% of annual opportunistic screening being cost effective. It is suggested that the following topics are worthy of further investigation: the effect of the implementation of a screening programme for AF on the uptake and maintenance of anticoagulation in patients aged 65 years and over; an evaluation of the role of CDSS in the diagnosis of cardiac arrythmias; the best method for routinely detecting paroxysmal AF; ways of improving healthcare professionals' performance in ECG interpretation; development of a robust economic model to incorporate data on new therapeutic agents for use as thromboprophylactic agents for patients with AF, and an evaluation of the relative risk of stroke for patients with incident as opposed to prevalent AF.

Targets and self monitoring in hypertension: randomised controlled trial and cost effectiveness analysis

OBJECTIVES

To assess whether blood pressure control in primary care could be improved with the use of patient held targets and self monitoring in a practice setting, and to assess the impact of these on health behaviours, anxiety, prescribed antihypertensive drugs, patients' preferences, and costs.

DESIGN

Randomised controlled trial.

SETTING

Eight general practices in south Birmingham.

PARTICIPANTS

441 people receiving treatment in primary care for hypertension but not controlled below the target of < 140/85 mm Hg.

INTERVENTIONS

Patients in the intervention group received treatment targets along with facilities to measure their own blood pressure at their general practice; they were also asked to visit their general practitioner or practice nurse if their blood pressure was repeatedly above the target level. Patients in the control group received usual care (blood pressure monitoring by their practice).

PRIMARY OUTCOME

change in systolic blood pressure at six months and one year in both intervention and control groups.

SECONDARY OUTCOMES

change in health behaviours, anxiety, prescribed antihypertensive drugs, patients' preferences of method of blood pressure monitoring, and costs.

RESULTS

400 (91%) patients attended follow up at one year. Systolic blood pressure in the intervention group had significantly reduced after six months (mean difference 4.3 mm Hg (95% confidence interval 0.8 mm Hg to 7.9 mm Hg)) but not after one year (mean difference 2.7 mm Hg (- 1.2 mm Hg to 6.6 mm Hg)). No overall difference was found in diastolic blood pressure, anxiety, health behaviours, or number of prescribed drugs. Patients who self monitored lost more weight than controls (as evidenced by a drop in body mass index), rated self monitoring above monitoring by a doctor or nurse, and consulted less often. Overall, self monitoring did not cost significantly more than usual care (251 pounds sterling (437 dollars; 364 euros) (95% confidence interval 233 pounds sterling to 275 pounds sterling) versus 240 pounds sterling (217 pounds sterling to 263 pounds sterling).

CONCLUSIONS

Practice based self monitoring resulted in small but significant improvements of blood pressure at six months, which were not sustained after a year. Self monitoring was well received by patients, anxiety did not increase, and there was no appreciable additional cost. Practice based self monitoring is feasible and results in blood pressure control that is similar to that in usual care.

Phylogeography of pollinator-specific sexually deceptive Chiloglottis taxa (Orchidaceae): evidence for sympatric divergence?

Divergence in sexually deceptive orchids is thought to occur through shifts in the attraction of specific pollinators, a process that is mediated by changes in the floral odours that lure sexually excited male insects. We investigated the origin of reproductive isolation in a sexually deceptive species complex of Chiloglottis R.Br. (Orchidaceae: Diurideae). Two geographically separated montane regions in eastern Australia were sampled, each containing sympatric pairs of orchid taxa presently found under the name, Chiloglottis pluricallata. Behavioural tests confirmed at least three distinct orchid taxa that specifically attract different pollinators. An artificial crossing experiment among two taxa from one region demonstrated their interfertility, and confirmed isolation to be a function of pollinator attraction. A phylogeographic analysis using amplified fragment length polymorphisms (AFLPs) indicated that samples from each geographical region are most closely related, a pattern consistent with in situ or sympatric divergence. However, an extensive population genetic study on two taxa from one region failed to entirely reject the possibility of intertaxon gene flow. Although clear genetic differentiation of the taxa is evident in two out of three sites where both grow in direct sympatry, overall, the two taxa are not strongly distinguished by AFLP markers. The reconstruction of a simple bifurcating pattern of divergence may be confounded by a combination of contemporary population-level processes operating within each taxon, the retention of ancestral polymorphism or intertaxon gene flow.

Family support for stroke: one year follow up of a randomised controlled trial

BACKGROUND

There is evidence that family support can benefit carers of stroke patients, but not the patients themselves.

OBJECTIVE

To extend the follow up of a single blind randomised controlled trial of family support for stroke patients and carers to one year to ascertain whether there were any late effects of the intervention.

METHODS

The study was a randomised controlled trial. Patients admitted to hospital with acute stroke who had a close carer were assigned to receive family support or normal care. Families were visited at home by a researcher 12 months after the stroke, and a series of questionnaires was administered to patient and carer.

RESULTS

The benefits to carers mostly persisted, though they were no longer statistically significant because some patients were lost to follow up. There was no evidence of any effects on patients.

CONCLUSION

Family support is effective for carers, but different approaches need to be considered to alleviate the psychosocial problems of stroke patients.

Systematic review and modelling of the investigation of acute and chronic chest pain presenting in primary care

OBJECTIVES

To ascertain the value of a range of methods - including clinical features, resting and exercise electrocardiography, and rapid access chest pain clinics (RACPCs) - used in the diagnosis and early management of acute coronary syndrome (ACS), suspected acute myocardial infarction (MI), and exertional angina.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, the Cochrane Library and electronic abstracts of recent cardiological conferences.

REVIEW METHODS

Searches identified studies that considered patients with acute chest pain with data on the diagnostic value of clinical features or an electrocardiogram (ECG); patients with chronic chest pain with data on the diagnostic value of resting or exercise ECG or the effect of a RACPC. Likelihood ratios (LRs) were calculated for each study, and pooled LRs were generated with 95% confidence intervals. A Monte Carlo simulation was performed evaluating different assessment strategies for suspected ACS, and a discrete event simulation evaluated models for the assessment of suspected exertional angina.

RESULTS

For acute chest pain, no clinical features in isolation were useful in ruling in or excluding an ACS, although the most helpful clinical features were pleuritic pain (LR+ 0.19) and pain on palpation (LR+ 0.23). ST elevation was the most effective ECG feature for determining MI (with LR+ 13.1) and a completely normal ECG was reasonably useful at ruling this out (LR+ 0.14). Results from 'black box' studies of clinical interpretation of ECGs found very high specificity, but low sensitivity. In the simulation exercise of management strategies for suspected ACS, the point of care testing with troponins was cost-effective. Pre-hospital thrombolysis on the basis of ambulance telemetry was more effective but more costly than if performed in hospital. In cases of chronic chest pain, resting ECG features were not found to be very useful (presence of Q-waves had LR+ 2.56). For an exercise ECG, ST depression performed only moderately well (LR+ 2.79 for a 1 mm cutoff), although this did improve for a 2 mm cutoff (LR+ 3.85). Other methods of interpreting the exercise ECG did not result in dramatic improvements in these results. Weak evidence was found to suggest that RACPCs may be associated with reduced admission to hospital of patients with non-cardiac pain, better recognition of ACS, earlier specialist assessment of exertional angina and earlier diagnosis of non-cardiac chest pain. In a simulation exercise of models of care for investigation of suspected exertional angina, RACPCs were predicted to result in earlier diagnosis of both confirmed coronary heart disease (CHD) and non-cardiac chest pain than models of care based around open access exercise tests or routine cardiology outpatients, but they were more expensive. The benefits of RACPCs disappeared if waiting times for further investigation (e.g. angiography) were long (6 months).

CONCLUSIONS

Where an ACS is suspected, emergency referral is justified. ECG interpretation in acute chest pain can be highly specific for diagnosing MI. Point of care testing with troponins is cost-effective in the triaging of patients with suspected ACS. Resting ECG and exercise ECG are of only limited value in the diagnosis of CHD. The potential advantages of RACPCs are lost if there are long waiting times for further investigation. Recommendations for further research include the following: determining the most appropriate model of care to ensure accurate triaging of patients with suspected ACS; establishing the cost-effectiveness of pre-hospital thrombolysis in rural areas; determining the relative cost-effectiveness of rapid access chest pain clinics compared with other innovative models of care; investigating how rapid access chest pain clinics should be managed; and establishing the long-term outcome of patients discharged from RACPCs.

Identification of stroke in the community: a comparison of three methods

BACKGROUND

Evidence concerning secondary prevention of cerebrovascular disease is not optimally used in clinical practice. A necessary first step is to identify those eligible for treatment. In primary care, this equates to setting up a register of prevalent stroke.

AIM

To compare three different methods for identifying prevalent cases of cerebrovascular disease in the community: general practice-based computer systems; population surveys; and hospital-based routine information systems.

DESIGN OF STUDY

Comparison of results of each method applied to a defined population and then assessed against reference criteria for cerebrovascular disease.

SETTING

A total of 5801 people aged 65 years or over, resident in seven practices situated within the South Birmingham Primary Care Trust area.

METHOD

The sensitivity, specificity, and predictive value of each method of identification were calculated against reference criteria applied by two investigators independently of each other.

RESULTS

The prevalence of reference criteria-validated cerebrovascular disease in patients aged 65 years or over was 8.2%. Overall, general practice-based computer systems had a sensitivity of 81.0%, a specificity of 97.2% and a positive predictive value (PPV) of 71.8%, but there was a wide range of sensitivity (33% to 90%) and PPV (42% to 92%) between practices. Patient survey and hospital information systems were less sensitive (75.7% and 28.4%, respectively) but had higher PPVs (77.5% and 89.2%, respectively). Thirty-nine per cent of patients with a history of cerebrovascular disease had not been admitted to hospital.

CONCLUSION

General practice-based computer systems can produce reasonably accurate prevalent stroke registers. In areas where these are poorly developed, patient survey is an alternative.

Mortality study of 18 000 patients treated with omeprazole

BACKGROUND

The long term safety of potent gastric acid suppressive therapy has yet to be established.

METHOD

General practice record review at a median interval of 26 months followed by retrieval of details of all deaths within four years using the UK National Health Service Central Registers in 17 936 patients prescribed omeprazole in 1993-1995. Death rates were compared with general population rates.

RESULTS

Records of 17 489 patients (97.5%) were examined. A total of 12 703 patients received further scripts for antisecretory drugs, 8097 for omeprazole only (65.6%): 3097 patients have died. All cause mortality was higher in the first year (observed/expected (O/E) 1.44 (95% confidence intervals (CI) 1.34-1.55); p<0.0001) but had fallen to population expectation by the fourth year. There were significant mortality increases in the first year, falling to or below population expectation by the fourth year, for deaths ascribed to neoplasms (1.82 (95% CI 1.58-2.08); p<0.0001), circulatory diseases (1.27 (95% CI 1.13-1.43); p<0.0001), and respiratory diseases (1.37 (95% CI 1.12-1.64); p<0.001). Increased mortality ascribed to digestive diseases (2.56 (95% CI 1.87-3.43); p<0.0001) persisted, although reduced. Increased mortality rates for cancers of the stomach (4.06 (95% CI 2.60-6.04); p<0.0001), colon and rectum (1.40 (95% CI 0.84-2.18); p=0.075), and trachea, bronchus, and lung (1.64 (95% CI 1.19-2.19); p<0.01) seen in the first year had disappeared by the fourth year but that for cancer of the oesophagus had not (O/E 7.35 (95% CI 5.20-10.09) (p<0.0001) in year 1; 2.88 (95% CI 1.62-4.79) (p<0.001) in year 4). Forty of 78 patients dying of oesophageal cancer had the disease present at registration. Twenty seven of those remaining cases had clinical evidence of Barrett's disease, stricture, ulcer, or oesophagitis at registration (O/E 3.30 (95% CI 2.17-4.80)). Six deaths occurred in patients with hiatal hernia or reflux only (O/E 1.02 (95% CI 0.37-2.22)) and five in patients without oesophageal disease (O/E 0.77 (95% CI 0.25-1.80)). No relationships were detected with numbers of omeprazole scripts received.

CONCLUSIONS

Increases in mortality associated with treatment are due to pre- existing illness, including pre-existing severe oesophageal disease. There was no evidence of an increased risk of oesophageal adenocarcinoma in those without oesophageal mucosal damage recorded at registration.

Comparison of estimates and calculations of risk of coronary heart disease by doctors and nurses using different calculation tools in general practice: cross sectional study

OBJECTIVE

To assess the effect of using different risk calculation tools on how general practitioners and practice nurses evaluate the risk of coronary heart disease with clinical data routinely available in patients' records.

DESIGN

Subjective estimates of the risk of coronary heart disease and results of four different methods of calculation of risk were compared with each other and a reference standard that had been calculated with the Framingham equation; calculations were based on a sample of patients' records, randomly selected from groups at risk of coronary heart disease.

SETTING

General practices in central England.

PARTICIPANTS

18 general practitioners and 18 practice nurses.

MAIN OUTCOME MEASURES

Agreement of results of risk estimation and risk calculation with reference calculation; agreement of general practitioners with practice nurses; sensitivity and specificity of the different methods of risk calculation to detect patients at high or low risk of coronary heart disease.

RESULTS

Only a minority of patients' records contained all of the risk factors required for the formal calculation of the risk of coronary heart disease (concentrations of high density lipoprotein (HDL) cholesterol were present in only 21%). Agreement of risk calculations with the reference standard was moderate (kappa=0.33-0.65 for practice nurses and 0.33 to 0.65 for general practitioners, depending on calculation tool), showing a trend for underestimation of risk. Moderate agreement was seen between the risks calculated by general practitioners and practice nurses for the same patients (kappa=0.47 to 0.58). The British charts gave the most sensitive results for risk of coronary heart disease (practice nurses 79%, general practitioners 80%), and it also gave the most specific results for practice nurses (100%), whereas the Sheffield table was the most specific method for general practitioners (89%).

CONCLUSIONS

Routine calculation of the risk of coronary heart disease in primary care is hampered by poor availability of data on risk factors. General practitioners and practice nurses are able to evaluate the risk of coronary heart disease with only moderate accuracy. Data about risk factors need to be collected systematically, to allow the use of the most appropriate calculation tools.

Using case-control studies for prescribing research

In this review, the principles of design, analysis and interpretation of case-control studies are illustrated by considering the evidence from case-control studies that link hormone replacement therapy to venous thromboembolism.

A systematic review of the evidence for rapid access chest pain clinics

To determine the impact of rapid access chest pain clinics (RACPC) on patient management, a systematic search (1966-2000) was performed of electronic databases, recent conference abstracts, citations of all identified studies, and by contact with other researchers. Studies of any design were included. Assessment of eligibility, methodological quality of studies and data abstraction was conducted independently by two reviewers. Outcome measures were sought in terms of admission rate of patients without acute coronary syndrome detection rate of acute coronary syndrome unrecognised by the GP, timing of specialist assessment of patients with stable angina and speed and accuracy of detection of those with non-cardiac chest pain. Nine relevant studies were found, but all had methodological flaws when considered as evaluative studies. All clinics described reviewed patients within 24 hours of referral. Only three studies made comparisons with control groups, none of which were randomised, and a further three provided follow-up data only. Limited data were found for all four outcome measures, indicating possible benefits of RACPCs. However, all findings could be explained by potential biases in the original studies. In conclusion, the evidence base for the introduction of rapid access chest pain clinics is poor. The introduction of these clinics should include a randomised prospective evaluation of their worth.

Process versus outcome indicators in the assessment of quality of health care

This paper reviews the relative strengths and weaknesses of outcome and process measures as performance indicators in health care. Differences in outcome may be due to case mix, how the data were collected, chance, or quality of care. Health care is only one determinant of health and other factors have important effects on health outcomes, such as nutrition, environment, lifestyle and poverty. The advantages of process measures are that they are more sensitive to differences in the quality of care and they are direct measures of quality. However, outcome measures are of greater intrinsic interest and can reflect all aspects of care, including those that are otherwise difficult to measure such as technical expertise and operator skill. Outcome indicators can be improved if efforts are made to standardize data collection and case mix adjustment systems are developed and validated. It is argued that this is worth doing only where it is likely that variations in health care might lead to significant variations in health outcome and where the occurrence of the outcome is sufficiently common that the outcome indicator will have the power to detect real differences in quality. If these conditions are not met, then alternative strategies such as process measurement and risk management techniques may be more effective at protecting the public from poor quality care.

Family support for stroke: a randomised controlled trial

BACKGROUND

Attention is currently focused on family care of stroke survivors, but the effectiveness of support services is unclear. We did a single-blind, randomised, controlled trial to assess the impact of family support on stroke patients and their carers.

METHODS

Patients with acute stroke admitted to hospitals in Oxford, UK, were assigned family support or normal care within 6 weeks of stroke. After 6 months, we assessed, for carers, knowledge about stroke, Frenchay activities index, general health questionnaire-28 scores, caregiver strain index, Dartmouth co-op charts, short form 36 (SF-36), and satisfaction scores, and, for patients, knowledge about stroke and use of services, Barthel index, Rivermead mobility index, Frenchay activities index, London handicap scale, hospital anxiety and depression scales, Dartmouth co-op charts, and satisfaction.

FINDINGS

323 patients and 267 carers were followed up. Carers in the intervention group had significantly better Frenchay activities indices (p=0.03), SF-36 scores (energy p=0.02, mental health p=0.004, pain p=0.03, physical function p=0.025, and general health perception p=0.02), quality of life on the Dartmouth co-op chart (p=0.01), and satisfaction with understanding of stroke (82 vs 71%, p=0.04) than those in the control group. Patients' knowledge about stroke, disability, handicap, quality of life, and satisfaction with services and understanding of stroke did not differ between groups. Fewer patients in the intervention group than in the control group saw a physiotherapist after discharge (44 vs 56%, p=0.04), but use of other services was similar.

INTERPRETATION

Family support significantly increased social activities and improved quality of life for carers, with no significant effects on patients.

Inter-rater reliability of the Frenchay activities index in patients with stroke and their careers

OBJECTIVE

To measure the inter-rater reliability of the interview-administered version of the Frenchay Activities Index (FAI).

DESIGN

Comparison of FAI score on the same person when administered by two raters (mean time between interviews 15.2 days).

SUBJECTS

Fifty-nine Oxfordshire residents who either had had a stroke (n = 35) or were the main carer (n = 24).

RESULTS

The 95% limits of agreement for the FAI totals were -9.9 to +8.4. The kappa statistic for nine of the 15 items showed a good level of agreement between the two research interviews (0.64-0.80). The other six items showed fair or moderate strength of agreement (0.26-0.52). Three items showed significant differences between the two raters p < 0.05 (Wilcoxon's sign paired rank sum test). The mean difference between the total scores was -0.76 (95% confidence interval from -1.98 to 0.46). Spearman's rho correlation coefficient for FAI totals of rater B against A was r(59) = 0.93 (p < 0.001).

CONCLUSION

The FAI is a reliable tool for measuring outcome following stroke. Suggestions are made to strengthen the reliability, and consequently the validity of the measure.

The accuracy of general practitioner records of smoking and alcohol use: comparison with patient questionnaires

BACKGROUND

General practitioner (GP) records are increasingly being used as sources of information on potential confounders such as smoking use and alcohol intake in epidemiological studies. The aim of this study was to assess the accuracy of GP records on smoking use and alcohol intake compared with data from patient questionnaires.

METHODS

Patients registered with 42 practices in Oxfordshire that agreed to take part in a post-marketing surveillance study of omeprazole were sent a postal questionnaire that included questions about alcohol and tobacco use. Two years later, data on these aspects of lifestyle were abstracted from the GP records.

RESULTS

A total of 892 patients agreed to take part in the study; 804 (90 per cent) completed the postal questionnaire, and the records of 856 (96 per cent) were reviewed. Information on smoking and alcohol use was present in 74 per cent and 63 per cent of GP records, respectively. Agreement between the two data sources was moderate for both smoking (kappa = 0.50) and alcohol use (kappa = 0.52). With regard to smoking, the main discrepancy between the two data sources was that 46 per cent (94/206) of patients who reported themselves as exsmokers were recorded as being never smokers in the GP record. With regard to alcohol, there were no systematic differences between the two data sources.

CONCLUSION

Data from GP records on smoking status and alcohol use are incomplete and subject to some misclassification. This is a source of potential failed adjustment for confounding, which should be considered in epidemiological studies that make use of these records.