A K Roalfe

Prevalence of atrial fibrillation in the general population and in high-risk groups: the ECHOES study

AIMSnTo establish the prevalence of atrial fibrillation (AF) in the general population in the UK, and in those with risk factors.nnnMETHODS AND RESULTSnThe prevalence of AF on electrocardiography was established in prospectively selected groups: 3960 randomly selected from the population, aged 45+; 782 with a previous diagnosis of heart failure; and 1062 with a record of myocardial infarction, hypertension, angina, or diabetes. Patients were also assessed clinically and with echocardiography. Mortality was tracked for 8 years. Atrial fibrillation was found in 78 of the random population sample (2.0%). Prevalence was 1.6% in women and 2.4% in men, rising with age from 0.2% in those aged 45-54 to 8.0% in those aged 75 and older. Half of all cases were in patients aged 75 and older. Only 23 of the 78 (29.5%) of those in AF took warfarin. Of the 782 patients, 175 (22.4%) with a diagnosis of heart failure were in AF, with normal left ventricular function in 95 (54.3%) of these. Atrial fibrillation was found in 14 of the 244 (5.7%) of those with a history of myocardial infarction, 15 of the 388 (3.9%) of those with hypertension, 15 of the 321 (4.7%) of those with angina, and 11 of the 208 (5.3%) of diabetics. Adjusting for age and sex, mortality was 1.57 times higher for those in AF.nnnCONCLUSIONnAtrial fibrillation is common in the elderly and those with clinical risk factors. Screening these groups would identify many with AF. Use of anticoagulation was low at the time of the initial assessments in the late 1990s; practice may have changed recently.

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 CHADS2, 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 CHADS2 (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 CHADS2, Rietbrock modified CHADS2, and CHA2DS2-VASc (CHA2DS2-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 CHADS2) to 0.62 (Rietbrock modified CHADS2), with all except the original CHADS2 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.

Ten-year prognosis of heart failure in the community: Follow-up data from the Echocardiographic Heart of England Screening (ECHOES) study

This study investigates the 10‐year survival in the ECHOES (Echocardiographic Heart of England Screening) study and examines factors associated with prognosis.

The potential role of NT-proBNP in screening for and predicting prognosis in heart failure: a survival analysis

Objective To determine the potential role of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in screening for and predicting prognosis in heart failure by examining diagnosis and survival of patients with a raised NT-proBNP at screening. Design Survival analysis. Setting Prospective substudy of the Echocardiographic Heart of England Screening study (ECHOES) to investigate 10-year survival in participants with an NT-proBNP level at baseline. Participants 594 participants took part in the substudy. Records of all participants in the ECHOES cohort were flagged during the screening phase which ended on 25 February 1999. All deaths until 25 February 2009 were coded. Outcome measures Logistic regression was used to examine whether NT-proBNP is useful in predicting heart failure at screening after adjustment for age, sex and cohort. Kaplan-Meier curves and log rank tests were used to compare survival times of participants according to NT-proBNP level. Cox regression was carried out to assess the prognostic effect of NT-proBNP after allowing for significant covariates and receiver operator curves were used to determine test reliability. Results The risk of heart failure increased almost 18-fold when NT-proBNP was 150u2005pg/mL or above (adjusted OR=17.7, 95% CI 4.9 to 63.5). 10-year survival in the general population cohort was 61% (95% CI 48% to 71%) for those with NT-proBNP ≥150u2005pg/mL and 89% (95% CI 84% to 92%) for those below the cut-off at the time of the initial study. After adjustment for age, sex and risk factors for heart failure, NT-proBNP level ≥150u2005pg/mL was associated with a 58% increase in the risk of death within 10u2005years (adjusted HR=1.58, 95% CI 1.09 to 2.30). Conclusions Raised NT-proBNP levels, when screening the general population, are predictive of a diagnosis of heart failure (at a lower threshold than guidelines for diagnosing symptomatic patients) and also predicted reduced survival at 10u2005years.

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

BackgroundHeart failure is a major cause of mortality and morbidity. As mortality rates are high, it is important that patients seen by general practitioners with symptoms suggestive of heart failure are identified quickly and treated appropriately. Identifying patients with heart failure or deciding which patients need further tests is a challenge. All patients with suspected heart failure should be diagnosed using objective tests such as echocardiography, but it is expensive, often delayed, and limited by the significant skill shortage of trained echocardiographers. Alternative approaches for diagnosing heart failure are currently limited. Clinical decision tools that combine clinical signs, symptoms or patient characteristics are designed to be used to support clinical decision-making and validated according to strict methodological procedures. The REFER Study aims to determine the accuracy and cost-effectiveness of our previously derived novel, simple clinical decision rule, a natriuretic peptide assay, or their combination, in the triage for referral for echocardiography of symptomatic adult patients who present in general practice with symptoms suggestive of heart failure.Methods/designThis is a prospective, Phase II observational, diagnostic validation study of a clinical decision rule, natriuretic peptides or their combination, for diagnosing heart failure in primary care. Consecutive adult primary care patients 55 years of age or over presenting to their general practitioner with a chief complaint of recent new onset shortness of breath, lethargy or peripheral ankle oedema of over 48 hours duration, with no obvious recurrent, acute or self-limiting cause will be enrolled. Our reference standard is based upon a three step expert specialist consensus using echocardiography and clinical variables and tests.DiscussionOur clinical decision rule offers a potential solution to the diagnostic challenge of providing a timely and accurate diagnosis of heart failure in primary care. Study results will provide an evidence-base from which to develop heart failure care pathway recommendations and may be useful in standardising care. If demonstrated to be effective, the clinical decision rule will be of interest to researchers, policy makers and general practitioners worldwide.Trial registrationISRCTN17635379

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.

Cost-effectiveness analysis of use of a polypill versus usual care or best practice for primary prevention in people at high risk of cardiovascular disease

Background Clinical trials suggest that use of fixed-dose combination therapy (‘polypills’) can improve adherence to medication and control of risk factors of people at high risk of cardiovascular disease (CVD) compared to usual care, but cost-effectiveness is unknown. Objective To determine whether a polypill is cost-effective compared to usual care and optimal guideline-recommended treatment for primary prevention in people already on statins and/or blood pressure lowering therapy. Methods A Markov model was developed to perform a cost-utility analysis with a one year time cycle and a 10 year time horizon to compare the polypill with usual care and optimal implementation of NICE Guidelines, using patient level data from a retrospective cross-sectional study. The model was run for ten age (40 years+) and gender-specific sub-groups on treatment for raised CVD risk with no history of CVD. Published sources were used to estimate impact of different treatment strategies on risk of CVD events. Results A polypill strategy was potentially cost-effective compared to other strategies for most sub-groups ranging from dominance to up to £18,811 per QALY depending on patient sub-group. Optimal implementation of guidelines was most cost-effective for women aged 40–49 and men aged 75+. Results were sensitive to polypill cost, and if the annual cost was less than £150, this approach was cost-effective compared to the other strategies. Conclusions For most people already on treatment to modify CVD risk, a polypill strategy may be cost-effective compared with optimising treatment as per guidelines or their current care, as long as the polypill cost is sufficiently low.

Aerobic exercise for vasomotor menopausal symptoms: A cost-utility analysis based on the Active Women trial

Objective To compare the cost-utility of two exercise interventions relative to a control group for vasomotor menopausal symptoms. Design Economic evaluation taking a UK National Health Service and Personal Social Services perspective and a societal perspective. Setting Primary care. Population Peri- and postmenopausal women who have not used hormone therapy in the past 3 months and experience ≥ 5 episodes of vasomotor symptoms daily. Methods An individual and a social support-based exercise intervention were evaluated. The former (Exercise-DVD), aimed to prompt exercise with purpose-designed DVD and written materials, whereas the latter (Exercise-Social support) with community exercise social support groups. Costs and outcomes associated with these interventions were compared to those of a control group, who could only have an exercise consultation. An incremental cost-utility analysis was undertaken using bootstrapping to account for the uncertainty around cost-effectiveness point-estimates. Main outcome measure Cost per quality-adjusted life-year (QALY). Results Data for 261 women were available for analysis. Exercise-DVD was the most expensive and least effective intervention. Exercise-Social support was £52 (CIs: £18 to £86) and £18 (CIs: -£68 to £105) more expensive per woman than the control group at 6 and 12 months post-randomisation and led to 0.006 (CIs: -0.002 to 0.014) and 0.013 (CIs: -0.01 to 0.036) more QALYs, resulting in an incremental cost-effectiveness ratio of £8,940 and £1,413 per QALY gained respectively. Exercise-Social support had 80%-90% probability of being cost-effective in the UK context. A societal perspective of analysis and a complete-case analysis led to similar findings. Conclusions Exercise-Social support resulted in a small gain in health-related quality of life at a marginal additional cost in a context where broader wellbeing and long-term gains associated with exercise and social participation were not captured. Community exercise social support groups are very likely to be cost-effective in the management of vasomotor menopausal symptoms.

What factors influence weight loss in participants of commercial weight loss programmes? Implications for health policy

BACKGROUNDnFinding effective referral policies for weight management services would have important public health implications.nnnAIMnHere we compare percentage weight change by referral methods, BMI categories and participants who have had attended weight loss programmes multiple times.nnnDESIGN AND SETTINGSnA prospective cohort study of 15,621 participants referred to 12-week behavioural weight loss programmes funded by the public health service in Birmingham, UK.nnnMETHODSnComparisons were made between GP versus self-referrals, BMI ≥40kg/m2-<40kg/m2 and multiple referrals compared to only one referral. Linear mixed modelling was used to assess percentage weight change after adjusting for covariates.nnnRESULTSnParticipants mean age was 48.5 years, 78.7% were of white ethnicity, 90.3% female and mean baseline BMI was 36.3kg/m2. There were no significant differences in percentage weight loss, between participants that self-referred and those that were referred by their general practitioner (GP) and no significant differences between baseline BMI categories. Referral to a weight loss programme more than once was associated with less weight loss at subsequent attendances (0.92%, 95% CI 0.70-1.14, p<0.001).nnnCONCLUSIONnAllowing self-referral to a weight loss programme widens access without compromising amount of weight lost. These programmes are beneficial for all categories of obesity, including those with a BMI ≥40kg/m2. Attending weight management programmes more than once results in less weight loss and that swapping to a different program may be advisable.

Are babies conceived during Ramadan born smaller and sooner than babies conceived at other times of the year? A Born in Bradford Cohort Study

Background It is not known whether infants exposed to intermittent maternal fasting at conception are born smaller or have a higher risk of premature birth than those who are not. Doctors are therefore unsure about what advice to give women about the safety of Ramadan fasting. This cohort study aimed to investigate these questions in Muslim mother–infant pairs to inform prenatal care. Methods Routinely collected data accessed from maternity records were the source for information. Mothers were considered exposed if they were Muslim and Ramadan overlapped with their infant conception date, estimated to be 14u2005days after the last menstrual period. Infants were included as exposed if their estimated conception date was in the first 21u2005days of Ramadan or 7u2005days prior to Ramadan. Results After adjusting for gestational age, maternal age, infant gender, maternal body mass index at booking, smoking status, gestational diabetes, parity and year of birth, there was no significant difference in birth weight between infants born to Muslim mothers who were conceived during Ramadan (n=479) and those who were not (n=4677) (adjusted mean difference =24.3u2005g, 95% CI −16.4 to 64.9). There was no difference in rates of premature births in exposed and unexposed women (5.2% vs 4.9%; OR=1.08, 95% CI 0.71 to 1.65). Conclusions Healthy Muslim women considering becoming pregnant prior to, or during Ramadan, can be advised that fasting does not seem to have a detrimental effect on the size (weight) of their baby and it appears not to increase the likelihood of giving birth prematurely.