Routes to diagnosis of heart failure: observational study using linked data in England

Alex Bottle, Dani Kim, Paul Aylin, Martin R Cowie, Azeem Majeed, Benedict Hayhoe

Dr Foster Unit, Department of Primary Care and Public Health, Imperial College London, 3 Dorset Rise, London EC4Y 8EN Alex Bottle Reader in Medical Statistics Dr Foster Unit, Department of Primary Care and Public Health, Imperial College London, 3 Dorset Rise, London EC4Y 8EN Dani Kim Research Assistant Dr Foster Unit, Department of Primary Care and Public Health, Imperial College London, 3 Dorset Rise, London EC4Y 8EN Paul Aylin Professor of Epidemiology and Public Health National Heart & Lung Institute, Royal Brompton Hospital, Imperial College London, Sydney St, Chelsea, London SW3 6NP Martin R Cowie Professor of Cardiology and Consultant Cardiologist Department of Primary Care and Public Health, Imperial College London, Charing Cross Campus, The Reynolds Building, St Dunstan's Road, London W6 8RP Azeem Majeed Professor of Primary Care Department of Primary Care and Public Health, Imperial College London, Charing Cross Campus, The Reynolds Building, St Dunstan's Road, London W6 8RP Benedict Hayhoe Clinical Lecturer in Primary Care

Correspondence to: A Bottle robert.bottle@imperial.ac.uk

Abstract

ObjectiveTimely diagnosis and management of heart failure (HF) is critical, but identification of patients with suspected HF can be challenging, especially in primary care. We describe the journey of people with HF in primary care from presentation through to diagnosis and initial management.

MethodsWe used the Clinical Practice Research Datalink (CPRD, primary care consultations linked to hospital admissions data and national death registrations for patients registered with participating primary care practices in England) to describe investigation and referral pathways followed by patients from first presentation with relevant symptoms to HF diagnosis, particularly alignment with recommendations of the National Institute for Health and Care Excellence (NICE) guideline for HF diagnosis.

Results36,748 patients had a diagnosis of HF recorded that met the inclusion criteria between 1st January 2010 and 31st March 2013. For 29,113 (79.2%) this was first recorded in hospital. In the five years prior to diagnosis, 15,057 patients (41.0%) had a primary care consultation with one of three key HF symptoms recorded, 17,724 (48.2%) attended for another reason, and 3,967 (10.8%) did not see their GP. Only 24% of those with recorded HF symptoms followed a pathway aligned with guidelines (echocardiogram and/or serum natriuretic peptide test and specialist referral); 44% had no echocardiogram, natriuretic peptide test or referral.

ConclusionsPatients follow various pathways to the diagnosis of HF. However, few appear to follow a pathway supported by guidelines for investigation and referral. There are likely to be missed opportunities for earlier HF diagnosis in primary care.

Word count: 2969 (main text)

Key words: heart failure

Key questions

What is already known about this subject?

Early identification of heart failure (HF) is key to effective management, but diagnosis can be challenging, especially in primary care

National Institute for Health and Care Excellence (NICE) guidelines recommend investigation of patients with suspected HF with echocardiogram and/or serum natriuretic peptide, followed by specialist referral; degree of adherence to this recommendation is not known

What does this study add?

Almost 80% of patients with HF appear to be diagnosed first in secondary care Of those with HF symptoms recorded in primary care, only 24% followed a

pathway aligned with NICE guidelines and rarely within the strict timeframe

How might this impact on clinical practice?

There may be missed opportunities for earlier HF diagnosis in primary care

Introduction

In heart failure (HF) accumulation of fluid in lungs and peripheries and reduction in blood flow to the muscles result in classic symptoms of breathlessness, ankle swelling and fatigue.[1] HF has considerable impact on patients and healthcare systems,[2] with high morbidity and mortality.[3] The Global Burden of Disease study estimated that some 40 million people had HF worldwide in 2015[4]; the estimated UK total is 550,000.[5]

Early identification is key to effective management.[1] Professionals rely initially on symptom recognition; the use of serum natriuretic peptide (either B-type natriuretic peptide (BNP) or N-terminal pro-B-type natriuretic peptide (NTproBNP)) as a screening test in symptomatic patients has been recommended for over ten years.[6-8]

Patients with HF often present first in primary care.[9] Identification and diagnosis in primary care is supported by professional guidelines [1,8,10] recommending minimum standards of investigation,[11] as well as medications improving symptoms and prognosis (beta-blockers and angiotensin-converting enzyme (ACE) inhibitors). In the National Health Service (NHS) in England, some elements of investigation and management in primary care (echocardiographic imaging, referral for ‘specialist assessment’, referral for exercise-based rehabilitation, and treatment with an ACE inhibitor or angiotensin II receptor blocker (ARB) and a beta-blocker) have for over ten years been supported by performance related payments under an incentivisation scheme, the Quality and Outcomes Framework.

National Institute for Health and Care Excellence (NICE) guidance recommends the following for patients presenting with HF symptoms in primary care:[8]

1. History and examination.2. For patients with history of acute myocardial infarction (AMI): referral for echocardiograph and ‘specialist’ assessment, usually by a Consultant Cardiologist or HF Nurse Specialist, for confirmation of diagnosis, classification, and planning of management, within 2 weeks.3. For patients without history of AMI: serum natriuretic peptide and electrocardiogram (ECG), followed by echocardiograph and referral for specialist assessment within 6 weeks subject to a BNP level of 100-400pg/ml or NTproBNP 400-2000pg/ml (patients with higher levels, BNP >400pg/ml or NTproBNP >2000pg/ml, require referral within 2 weeks).

Diagnosis and management of HF in primary care has been criticized, with evidence of both under- [12,13] and over-diagnosis,[14] and no improvement in survival over nearly 15 years.[15] Professionals may fail to adhere to guidance and lack confidence in investigations and treatments.[12,16,17] This has changed little, despite new guidance and incentivisation.[15,16,18] However, a clear picture of identification and management pathways for HF in primary care is currently lacking. Using linked primary and secondary care routinely collected data, we sought to characterise the journey of patients with HF symptoms in NHS primary care in England through investigation, treatment and referral, assessing potential for earlier diagnosis.

Methods

Data sourcesThe Clinical Practice Research Datalink (CPRD) is a database of pseudonymised electronic records from about 7% of UK general practices from 1987 to the present, considered representative of the UK population.[19] Primary care records are linked nationally to hospital admissions (Hospital Episode Statistics, HES) and the death registry (Office for National Statistics, ONS).

Patient cohort and subgroupsWe searched for patients with HF diagnosed between 1st January 2010 and 31st March 2013. For each patient, diagnosis date was the first coded record of HF, either in the primary care record or in hospital admission data. We identified primary care consultations and hospital admissions for HF using codes by Hawkins et al [20] augmented by our local clinicians (see Appendix). In HES, the earliest record of HF ICD10 codes recorded as either primary or secondary diagnoses was used.

The following exclusion criteria applied: CPRD records at practices not linked to HES, patients not registered in a CPRD practice for the whole ten-year period, and standard CPRD data quality exclusions regarding “up to standard” practices and patients with “acceptable data quality” (see Appendix).

Published sets of clinical codes for patient characteristics, tests, medications and referrals were used whenever available (see Appendix), tracking back five years before the date of diagnosis. For example, comorbidities from the Charlson set were defined as per Khan et al [21], with some extra comorbidities defined by our team. Otherwise, codes were identified using the CPRD medical and product dictionaries.

Pathway definitionsWe divided patients into two main groups according to primary care consultations in the five years before HF diagnosis: those with a primary care record of HF symptoms, and those with a primary care consultation but no recorded HF symptoms.

In the first group, we classified management into seven ‘pathways’ depending on tests, medications and referrals recorded. Pathway #1 comprised patients investigated in accordance with NICE recommendations (echocardiogram and/or serum natriuretic peptide test, and a referral to a specialist): we refer to this as the ‘NICE recommended pathway’ as a shorthand, although for the most part we did not incorporate the guideline’s timeframe. Partial concordance with guidelines was defined as Pathway #2 (echocardiogram and/or serum natriuretic peptide test, but no referral) or Pathway #4 (referral only). Patients who had no investigations recorded but were on appropriate medications for HF were categorised as Pathway #3a (put on a new type of medication) or Pathway #3b (already on medication). Medications of interest were ACE inhibitors, ARBs, and HF-specific beta-blockers (HF-BB). Pathway #5 (‘Other pathway’) covered those who had received other relevant management options, such as smoking cessation advice, influenza vaccination, an electrocardiogram (ECG) and/or a non HF-specific beta-blocker. Finally, Pathway #6 (‘No

pathway followed’) covered patients with recorded symptom(s) who did not appear to receive any management.

For the second group, who saw their GP but had no record of HF symptoms, the same set of pathways was applied using consultation records in the 5 years before HF diagnosis.

Statistical analysisPatient characteristics were summarized for all patients, whilst comorbidities were examined for those presenting to their GP with a HF symptom before diagnosis. Data were reported as absolute numbers and proportions with p values from chi-squared tests. Analyses were conducted using SAS v9.4.

Results

Patient characteristicsBetween 1st January 2010 and 31st March 2013, 36,748 patients had a diagnosis of HF recorded in CPRD practices that met the inclusion criteria and were included in the analysis. 29,113 (79.2%) had this first recorded in hospital data (HES) and 7,635 (20.8%) in primary care. Half were female and nearly one in three was aged 85 or over; nine in ten had at least one potentially relevant comorbidity, with nearly half having three or more, especially hypertension (69.9%), chronic pulmonary disease (33.9%), and coronary artery disease (31.6%) (Table 1).

15,057 patients (41.0%) had a primary care consultation with one of the three HF symptoms recorded before diagnosis (Table 2); 21% presented with any two and just 2% presented with all three. The commonest symptom was breathlessness, present in 80% of the 15,057. Half had a primary care consultation pre-diagnosis but with some other symptom recorded, and the remaining 11% had no primary care consultation prior to diagnosis.

Figures 1 and 2 show patients in each of the two main groups split by the elements of the NICE-recommended pathway; Table 3 provides more detail on their management. The remaining 3,967 patients had no contact with primary care in the five years before diagnosis and were hospitalised for HF, giving this hospital admission date as the date of their diagnosis. We did not consider them further in the analysis.

In addition to categorising patients based on HF symptom recorded in primary care, we also examined whether HF was first recorded in primary or secondary care; we use “GP-diagnosed” and “hospital-diagnosed” as shorthand for this. One in five patients were GP-diagnosed, of whom almost all (97%) had seen the GP for some reason in the previous year and just over half (55%) had presented with HF symptoms in the previous five years. Nearly four in five patients were hospital-diagnosed, of whom most (89%) had seen the GP for some reason in the previous year and a third (37%) had an HF symptom recorded in a GP consultation in the previous five years.

Patients with a record of HF symptoms in a primary care consultation

Nearly one in four (23.6%) of the 15,057 patients with HF symptoms recorded before diagnosis followed the NICE-recommended pathway (#1) of an echocardiogram and/or serum natriuretic peptide test and a specialist referral; another 14.4% were referred without either investigation (Figure 1, Table 3). GP-diagnosed patients were more than twice as likely to be on the NICE-recommended pathway (#1) than hospital-diagnosed ones. Of those not referred for any element of the NICE pathway, 3,705 (= 926 + 2779) or a quarter of this group were already taking or started relevant medication (Pathways #3a and #3b) on presentation of HF symptoms. In the 9% of this group on no pathway, subsequent hospital diagnosis was much more likely than GP-diagnosis.

Considering adherence to NICE recommended timeframes, 1,991 (13.2% of the 15,057) had had a previous AMI at the time of their first symptom, of whom only 23 (1.2%) completed the pathway within the recommended two weeks. 13,066 (86.8% of the 15,057) had not had a previous MI at the time of their first symptom, of whom 511 (3.9%) completed the pathway within the recommended six weeks.

Patients with only a record of non-HF symptoms in a primary care consultation Nearly one in eight (13.2%) of the 17,724 with only non-HF symptoms recorded in primary care before diagnosis followed the NICE-recommended pathway (#1); another 12.5% were referred without recorded investigation (Figure 2, Table 3). Of those 3,922 (= 1,606 + 134 + 1,918 + 264 from Figure 2) patients referred for an echo without recorded HF symptoms, 1461 (37%) had circulatory disorders recorded at the consultation at which the referral was made, including 786 (20%) that were actually HF. One in four of this group followed no pathway: again, subsequent hospital diagnosis was much more likely than GP diagnosis.

Discussion

Summary of findings

Patients took many routes to a heart failure diagnosis. Only one in five patients with recognised HF had this first recorded in a primary care consultation although almost all of these had seen a GP in the year before this diagnosis date, almost half with recorded HF symptoms. The remaining four in five had HF recorded for the first time during a hospital admission; the vast majority of these had also seen a GP in the previous year, 37% with recorded HF symptoms.

In the five years before diagnosis, only 11% had no primary care consultation. Of the 41% of our sample with a primary care consultation with one of the three key HF symptoms, management aligned with NICE guidance was documented for nearly one in four (Pathway #1): only 4% followed it within six weeks. Another one in seven were referred without record of either investigation (Pathway #4).

For the 48% of patients who had a primary care consultation with only non-HF symptoms recorded, the picture was also mixed. One in nine followed the NICE-recommended pathway, suggesting that the GP suspected HF but did not record an HF symptom. This is supported by the fact that HF was recorded as a diagnosis for 20% of these patients during the consultation when the referral was made.

Comparison with other studies

CPRD has recently been used to look at prognosis following HF diagnosis in primary care and secondary outpatient care.[22] Of nearly 78,000 patients identified with HF in primary or secondary care in that study between 1997 and 2010, 42% were first recorded in primary care and 58% on hospital admission. Our data, covering patients diagnosed between 2010 and 2013, suggest a more extreme differential of 21% and 79%. Inspection of our full CPRD extract dating back in 1997 reveals a steady rise in the proportion of patients diagnosed in hospital from about 50% in 2003 to about 80% in 2013. Reasons for this are unclear. It is possible that increasing familiarity with guidelines has led GPs to be cautious in diagnosing and treating HF in primary care based on clinical assessment: they may be more likely to await recommended investigations and specialist assessment. Pressure on secondary care diagnostic services may lead to some patients then presenting to hospital acutely whilst still under investigation. Patients admitted to hospital for HF without a prior diagnosis of HF in primary care have worse prognosis and management.[22] Much less is known about what happens before diagnosis, and ours is the first study to our knowledge mapping out the routes to a diagnosis of HF.

Strengths

Almost 100% of England’s population has access to primary and secondary care. The large data source provides sufficient sample size to describe the varied routes to a diagnosis of HF in real-world practice. The CPRD population is broadly representative of the UK population in terms of age, sex and ethnicity, and the database is well used in research.[19] HES covers all NHS hospitals in England with excellent coverage and highly accurate primary diagnosis and procedure coding [23]. The CPRD-HES-ONS linkage allows one to track patient pathways through the whole system, rare in other countries.

Limitations

CPRD data are entered by GPs during routine consultations and not for the purpose of research. Their use allows auditing for clinical quality improvement but also supports claims relating to financially incentivized activities[24-26]. Therefore, those required by schemes such as the UK’s Quality and Outcomes Framework may be more likely to be used than, for example, symptom codes.[27] However, it is recognized that coding in primary care remains highly variable.[24]

We divided our cohort based on recording of HF symptoms in GP consultations. The validity of this approach depends both on patients reporting symptoms and, more importantly, GPs recording them as Read codes; free text is no longer available in CPRD. We found a number of patients following the NICE HF pathway despite having none of the three main symptoms entered for that consultation. Instead, a variety of codes for procedures, examination and diagnoses were listed, with over half the patients having circulatory system disorders.

Another apparent anomaly is that 18% of patients referred for an echocardiogram actually had a diagnosis of HF recorded in the same consultation. Some GPs likely wished to code a

working diagnosis whilst following the pathway for investigation. Of course, other GPs may wish to have the diagnosis confirmed by investigations before ‘committing themselves’ by entering the code for HF in the notes, leading to the variation we found.

As with many epidemiological studies, case designation relies primarily on physician diagnosis rather than objective investigations. While there is evidence of underdiagnosis [28], a UK study that used an expert panel found that perhaps a third of patients may be incorrectly labelled as having HF.[16] Nevertheless, the working diagnosis is arguably the most relevant definition when examining prescribing behaviour.[20]

Early identification and classification of HF is key to effective management,[1] with an important distinction to be made between patients who have HF with reduced ejection fraction (HFrEF), where conventional medical therapies are effective in improving outcomes, and HF with preserved ejection fraction (HFpEF), where they generally are not.[28] This distinction is generally not well made in primary care[28], and relevant Read codes are rarely used. We were therefore unable to distinguish between the two.

Our definitions of the various pathways following GP consultation depended on several elements. Both referrals and echocardiograms may be made for other cardiac problems and are not necessarily specific for HF, but we have made the assumption that in our cohort, consisting of patients with HF recorded at some point, these were made for suspected HF. Serum natriuretic peptide testing was recommended in the 2005 European Society of Cardiology and the August 2010 NICE guidance but only available for a minority of practices during our study period. It is now more widely used, though threshold values are still under discussion.[9]

Implications for policy and practice

There are significant challenges in the identification, diagnosis and management of HF in primary care.[9] HF manifests itself in different ways, resulting in variation in patients’ health-seeking behaviour and GPs’ decision-making. Sudden onset, severe symptoms will lead the patients straight to the emergency department, bypassing earlier diagnosis by the GP. In contrast, patients with more insidious symptoms of HF may not see their GP in the early stages but wait instead until symptoms worsen and then attend the emergency department, perhaps influenced by actual or perceived problems with GP access. Others may see their GP with several different problems and fail to mention HF symptoms until the GP’s suspicions are at last raised.

From the GP’s perspective, the diagnosis is made harder by the lack of specificity of HF symptoms and the confusion with respiratory conditions[12] (one in three of our cohort had COPD compared with just 2% for the general population[29] and 11% for patients aged 75-79),[30] limited time availability, limited access to investigations, and low confidence in interpretation of investigation results.[9] Whilst clear clinical guidelines exist, perceived information overload as well as a belief that they do not apply to all patients mean that GPs do not always use them[9] and not all will be aware of them. Our results suggest that NICE guidelines (currently being updated) are not followed in primary care for the majority of patients who go on to be diagnosed with HF, with a significant majority being diagnosed in

the acute, secondary care setting. Finally, uncertainty about pharmacological management strategies, and concerns about co-morbidity and polypharmacy, especially in elderly patients,[9] complicates initial management; long waiting lists and limited availability of serum natriuretic peptide testing and specialist clinics may also prove a disincentive to GPs in referring patients.[9]

Conclusions

Patients follow various routes through the NHS to diagnosis of HF. Most continue to be diagnosed in hospital despite many presenting earlier in primary care with suggestive symptoms. Further research is needed to understand how GPs react to patients presenting with these symptoms and how they use current guidelines: there appears to be considerable opportunity to improve the early management of these patients in primary care.

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Competing interests statement

All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf and declare: AB, DK and PA had financial support from Dr Foster® for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work. AM and BH are both general practitioners working in the NHS.

Contributor statement

AB, DK and BH conceived and designed this study. AB and DK prepared the data; DK carried out the analysis, overseen by AB and BH. All authors took part in interpreting the data for this study. All authors commented on and helped to revise drafts of this paper. All authors have approved the final version. AB is the guarantor.

Transparency declaration

AB affirms that the manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.

Ethical Approval

We have approval from the Secretary of State and the Health Research Authority under Regulation 5 of the Health Service (Control of Patient Information) Regulations 2002 to hold confidential data and analyse them for research purposes (CAG ref 15/CAG/0005). We have approval to use them for research and measuring quality of delivery of healthcare, from the London - South East Ethics Committee (REC ref 15/LO/0824). The CPRD Group has obtained ethical approval from a National Research Ethics Service Committee (NRES) for all purely observational research using anonymised CPRD data. This study has been carried out as part of the work approved by their Independent Scientific Advisory Committee (ISAC) with protocol number 16_003RAR.

Funding

The Dr Foster Unit at Imperial College London is partially funded by a grant from Dr Foster®, a private healthcare information company. The Dr Foster Unit at Imperial College London is partly funded by research grants from the National Institute for Health Research Health Services Research. Prof Cowie’s salary is supported by the NIHR Cardiovascular Biomedical Research Unit at the Royal Brompton Hospital, London.

Statement of independence of researchers from funders and role of funders

None of the funders had any role in the conception, design, analysis or reporting of this study.

Patient involvement

Patients were not actively involved in this study.

Patient consent form

There are no identifiable patients in this study.

Acknowledgments

The Dr Foster Unit at Imperial is affiliated with the National Institute of Health Research (NIHR) Imperial Patient Safety Translational Research Centre. The NIHR Imperial Patient Safety Translational Centre is a partnership between the Imperial College Healthcare NHS Trust and Imperial College London. The Dr Foster Unit at Imperial College are grateful for support from the NIHR Biomedical Research Centre funding scheme. The views and opinions expressed herein are those of the authors and do not necessarily reflect those of the NHS, the NIHR, MRC, CCF, NETSCC, the HSR programme or the Department of Health.

Data sharing

Due to information governance rules applicable to CPRD, no data are available for sharing.

References

[1] Ponikowski P, Voors AA, Anker SD, Bueno H, Cleland JGF, Coats AJS, et al. 2016 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: The Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC). Eur Heart J 2016;37(27):2129–200.

[2] Hobbs FDR, Doust J, Mant J, Cowie MR. Diagnosis of heart failure in primary care. Heart 2010;96(21):1773–1777.

[3] Roger VL. Epidemiology of Heart Failure. Circ Res 2013;113(6):646–59.

[4] GBD 2015 Disease and Injury Incidence and Prevalence Collaborators. Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet 2016; 388(10053):1545–1602.

[5] Bhatnagar P, Wickramasinghe K, Williams J, Rayner M, Townsend N. The epidemiology of cardiovascular disease in the UK 2014. Heart 2015;101(15):1182–9. [6] Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE, Drazner MH, Fonarow GC, Geraci SA, Horwich T, Januzzi JL, Johnson MR, Kasper EK, Levy WC, Masoudi FA, McBride PE, McMurray JJV, Mitchell JE, Peterson PN, Riegel B, Sam F, Stevenson LW, Wilson Tang WH, Tsai EJ, Wilkoff BL. 2013 ACCF/AHA Guideline for the Management of Heart Failure. J Am Coll Cardiol 2013;62(16):e147-e239.

[7] Guidelines for the diagnosis and treatment of chronic heart failure: executive summary (update 2005): The Task Force for the Diagnosis and Treatment of Chronic Heart Failure of the European Society of Cardiology. Eur Heart J 2005;26(11):1115–40.

[8] National Institute of Health and Care Excellence. Chronic heart failure: national clinical guideline for diagnosis and management in primary and secondary care. National Clinical Guideline Centre; 2010.

[9] Smeets M, Van Roy S, Aertgeerts B, Vermandere M, Vaes B. Improving care for heart failure patients in primary care, GPs’ perceptions: a qualitative evidence synthesis. BMJ Open 2016;6(11):e013459.

[10] Scottish Intercollegiate Guidelines Network. SIGN 147 Management of chronic heart failure: a national clinical guideline. SIGN; 2016.

[11] Cleland J, Cohan-Solal A, Cosin Aguilar J, Dietz R, Eastaugh J, Follath F, et al. Management of heart failure in primary care (the IMPROVEMENT of heart failure programme): an international survey. Lancet 2002;360:1631–39.

[12] van Riet EES, Hoes AW, Limburg A, Landman MAJ, van der Hoeven H, Rutten FH. Prevalence of unrecognized heart failure in older persons with shortness of breath on exertion: Unrecognized HF in older persons with shortness of breath on exertion. Eur J Heart Fail 2014 Jul;16(7):772–7.

[13] Morgan S, Smith H, Simpson I, Liddiard GS, Raphael H, Pickering RM, et al. Prevalence and clinical characteristics of left ventricular dysfunction among elderly patients in general practice setting: cross sectional survey. BMJ 1999;318(7180):368–372.

[14] Valk MJ, Mosterd A, Broekhuizen BD, Zuithoff NP, Landman MA, Hoes AW, et al. Overdiagnosis of heart failure in primary care: a cross-sectional study. Br J Gen Pract 2016;66(649):e587–92.

[15] Taylor CJ, Ryan R, Nichols L, Gale N, Hobbs FR, Marshall T. Survival following a diagnosis of heart failure in primary care. Fam Pract 2017;cmw145.

[16] Hancock HC, Close H, Fuat A, Murphy JJ, Hungin APS, Mason JM. Barriers to accurate diagnosis and effective management of heart failure have not changed in the past 10 years: a qualitative study and national survey. BMJ Open 2014;4(3):e003866.

[17] Dahlstrom U, Hakansson J, Swedberg K, Waldenstrom A. Adequacy of diagnosis and treatment of chronic heart failure in primary health care in Sweden. Eur J Heart Fail 2009;11(1):92–8.

[18] Brettell R, Soljak M, Cecil E, Cowie MR, Tuppin P, Majeed A. Reducing heart failure admission rates in England 2004-2011 are not related to changes in primary care quality: national observational study. Eur J Heart Fail 2013;15(12):1335–42.

[19] Herrett E, Gallagher AM, Bhaskaran K, Forbes H, Mathur R, van Staa T, Smeeth L. Data Resource Profile: Clinical Practice Research Datalink (CPRD). Internat J Epidemiol 2015;827–836.

[20] Hawkins NM, Scholes S, Bajekal M, Love H, O'Flaherty M, Raine R, Capewell S. Community care in England: reducing socioeconomic inequalities in heart failure. Circulation 2012;126(9):1050-7.

[21] Khan NF, Perera R, Harper S, Rose PW. Adaptation and validation of the Charlson Index for Read/OXMIS coded databases. BMC Family Practice 2010;11:1.

[22] Koudstaal S, Pujades-Rodriguez M, Denaxas S, Gho JM, Shah AD, Yu N, Patel RS, Gale CP, Hoes AW, Cleland JG, Asselbergs FW, Hemingway H. Prognostic burden of heart failure recorded in primary care, acute hospital admissions, or both: a population-based linked

electronic health record cohort study in 2.1 million people. Eur J Heart Fail 2016 Dec 23 [Epub ahead of print].

[23] EM Burns, E Rigby, R Mamidanna, A Bottle, P Aylin, P Ziprin, OD Faiz. Systematic review of discharge coding accuracy. J Pub Health 2011;34(1):138-148.

[24] Jordan K, Porcheret M, Croft P. Quality of morbidity coding in general practice computerized medical records: a systematic review. Fam Pract 2004;21(4):396-412.

[25] Gray J, Orr D, Majeed A. Use of Read codes in diabetes management in a south London primary care group: implications for establishing disease registers BMJ 2003; 326:1130.

[26] Doran T, Fullwood C, Gravelle H, Reeves D, Kontopantelis E, Hiroeh U, Roland M. Pay-for-performance programs in family practices in the United Kingdom. N Engl J Med 2006;355:375–384.

[27] Deaton C, Benson J. Time for correct diagnosis and categorisation of heart failure in primary care. Br J Gen Pract 2016;66(652):554–5.

[28] Fuat A, Hungin APS, Murphy JJ. Barriers to accurate diagnosis and effective management of heart failure in primary care: qualitative study. BMJ 2003;326(7382):196.

[29] Quality and Outcomes Framework 2015-16. Recorded disease prevalence, achievements and exceptions. NHS Digital 2016. Available at URL: http://content.digital.nhs.uk/pubs/qof1516 (accessed Sep 1 2017)

[30] Melzer D, Correa Delgado J, Winder R, Masoli J, Richards S, Ble A. The Age UK almanac of disease profiles in later life. A reference on the frequency of major diseases, conditions and syndromes affecting older people in England. UEMS Ageing Research Group 2015. Available at URL: http://www.ageuk.org.uk/Documents/EN-GB/For-professionals/Research/Age_UK_almanac_FINAL_9Oct15.pdf?dtrk=true (accessed Sep 1 2017)

Figure 1. Pathways to diagnosis for patients presenting to their GP before their HF diagnosis with HF symptoms recorded (BNP=serum natriuretic peptide)

Figure 2. Pathways to diagnosis for patients presenting to their GP before their HF diagnosis with only non-HF symptoms recorded (BNP=serum natriuretic peptide)

Table 1. Patient characteristics: at diagnosis or before presentation of first symptom by diagnosis source

Total Primary care

Hospital

Factor N % N % N %GenderMale 18,440 50.2% 4,146 54.3% 14,297 49.1%Female 18,308 49.8% 3,489 45.7% 14,819 50.9%Age at diagnosis or first HF symptomMean 76.1 SD 14.4 75.8 SD 12.8 76.2 SD 14.8<45 1,251 3.4% 153 2.0% 1,098 3.8%45-64 5,427 14.8% 1,156 15.1% 4,271 14.7%65-74 6,707 18.3% 1,660 21.7% 5,047 17.3%75-84 11,628 31.6% 2,662 34.9% 8,966 30.8%≥85 11,735 31.9% 2,004 26.2% 9,731 33.4%Comorbidities before first symptom*None 1,355 9.0% 451 10.8% 904 8.3%Any of the following 13,702 91.0% 3,714 89.2% 9,988 91.7%Atrial fibrillation 3,684 24.5% 1,021 24.5% 2,663 24.4%Other arrhythmias 2,245 14.9% 667 16.0% 1,578 14.5%Myocardial infarction 2,142 14.2% 662 15.9% 1,480 13.6%Hypertension 10,529 69.9% 2,820 67.7% 7,709 70.8%Stroke 1,663 11.0% 410 9.8% 1,253 11.5%Diabetes 3,142 20.9% 807 19.4% 2,335 21.4%Congenital heart disease

124 0.8% 28 0.7% 96 0.9%

Coronary artery disease

4,760 31.6% 1,285 30.9% 3,475 31.9%

Peripheral vascular disease

1,719 11.4% 415 10.0% 1,304 12.0%

Myocarditis 160 1.1% 31 0.7% 129 1.2%Renal disease 3,746 24.9% 924 22.2% 2,822 25.9%Chronic pulmonary disease

5,098 33.9% 1,212 29.1% 3,886 35.7%

Number of comorbidities before first symptom*0 1,355 9.0% 451 10.8% 904 8.3%1 3,006 20.0% 885 21.2% 2,121 19.5%2 3,450 22.9% 951 22.8% 2,499 22.9%3 3,069 20.4% 797 19.1% 2,272 20.9%≥4 4,177 27.7% 1,081 26.0% 3,096 28.4%

* denominator=patients with pre-diagnosis symptoms; numerator= patients with comorbidity recorded before the date of first symptom (defined as the earliest recorded symptom during the 5 years pre-diagnosis period, including the diagnosis date)

Table 2. Proportion of patients with heart failure symptom* before diagnosis by symptom typeBy symptom type N % of total % of patients with

HF symptomsBreathlessness 12,019 32.7% 79.8%Breathlessness only (no fatigue or ankle swelling)

8,683 23.6% 57.7%

Fatigue 3,382 9.2% 22.5%Fatigue only (no breathlessness or ankle swelling)

1,322 3.6% 8.8%

Ankle swelling 3,586 9.8% 23.8%Ankle swelling only (no breathlessness or fatigue)

1,496 4.1% 9.9%

Any two symptoms 3,182 8.7% 21.1%All three symptoms 374 1.0% 2.5%Total seeing GP pre-diagnosis with HF symptom(s) recorded

15,057 41.0% 100.0%

Total seeing GP pre-diagnosis but with other symptom recorded

17,724 48.2% -

Total with no pre-diagnosis GP contact 3,967 10.8% -

Table 3. Management pathways after first symptom*, overall and by diagnosis source

Management pathway after first HF symptom* Management of patients with no HF pre-diagnosis symptoms**

PathwayTotal Primary care Hospital Total Primary care Hospital

N (%) N (%) N (%) N (%) N (%) N (%)#1 (NICE) 3,555 (23.6) 1,636 (39.3) 1,919 (17.6) 2,336 (13.2) 1,118 (32.2) 1,218 (8.5)

#2 2,753 (18.3) 1,267 (30.4) 1,486 (13.6) 2,026 (11.4) 989 (28.5) 1,037 (7.3)

#3a 926 (6.1) 155 (3.7) 771 (7.1) 4,012 (22.6) 390 (11.2) 3,622 (25.4)

#3b 2,779 (18.5) 374 (9.0) 2,405 (22.1)

#4 2,166 (14.4) 442 (10.6) 1,724 (15.8) 2,210 (12.5) 361 (10.4) 1,849 (13.0)

#5 1,522 (10.1) 166 (4.0) 1,356 (12.4) 2,844 (16.0) 250 (7.2) 2,594 (18.2)

#6 (none) 1,356 (9.0) 125 (3.0) 1,231 (11.3) 4,296 (24.2) 362 (10.4) 3,934 (27.6)Total 15,057 4,165 10,892 17,724 3,470 14,254Definitions of pathways: #1 Echo and/or BNP, and referral (NICE); #2 Echo and/or BNP, but no referral; #3a No echo, BNP or referral, but put on a new medication (ACEI/ARB/HF-BB); #3b No echo, BNP or referral, but already on a medication (ACEI/ARB/HF-BB); #4 Referral only; #5 Other pathway (had some kind of management e.g. given ECG/smoking advice/flu jab and already on or put on a beta-blocker); #6 No pathway followedƗ p value for chi-square test of independence between the proportions in primary care and hospital patients were all significant at 0.001* where management came after the first symptom which was recorded during the 5 years pre-diagnosis period (including the diagnosis date)** management recorded during the 5 years pre-diagnosis period (including the diagnosis date)