title: Prognosis of undiagnosed chest pain: linked electronic health record cohort study.
abstract: ObjectiveTo ascertain long term cardiovascular outcomes in patients whose chest pain remained undiagnosed six months after first presentation.DesignCohort study.SettingUK electronic health record database (CALIBER) linking primary care, secondary care, coronary registry, and death registry information.Participants172 180 adults aged ≥18 from 223 general practices presenting with a first episode of recorded chest pain, classified from medical records as diagnosed (non-coronary condition or angina) or undiagnosed (cause unattributed) at first consultation between 2002 and 2009 and with no previous record of cardiovascular disease.Main outcome measuresFatal or non-fatal cardiovascular events over 5.5 years' follow-up. Adjustments were made for age, sex, deprivation, body mass index, smoking status, year of index presentation, and previous records of diabetes or hypertension or previous prescriptions for lipid lowering drugs.ResultsAt the index presentation, 72.4% of patients (124 688) did not have a cause attributed for their chest pain; 118 687 (95.2%) of these did not receive any type of cardiovascular diagnosis over the next six months. Only a minority of patients in all three groups (non-coronary 2.0% (769 of 39 232); unattributed 11.7% (14 582 of 124 688); angina 31.5% (2606 of 8260)) had a recorded cardiac diagnostic investigation in the first six months after presentation. The long term incidence of cardiovascular events was higher in those whose chest pain remained unattributed after six months (5126 of 109 628; 4.7%) compared with patients with an initial diagnosis of non-coronary pain (1073 of 36 097; 3.0%) (adjusted hazard ratios for 0.5-1 year after presentation: 1.95, 95% confidence interval 1.66 to 2.31; for 1-3 years: 1.35, 1.23 to 1.48); for 3-5.5 years: 1.21, 1.08 to 1.37). Owing to the larger number of patients in the unattributed group, there were more excess myocardial infarctions in the long term in this group (214 more than expected based on the rate in the non-coronary group) than in the angina group (132 more than expected). Patients who had cardiac diagnostic investigations in the first six months had a higher long term risk of cardiovascular events, regardless of the initial chest pain label. Incidence of unattributed chest pain and angina decreased between 2002 (124 per 10 000 person years and 13 per 10 000 person years, respectively) and 2009 (107 per 10 000 person years and 5 per 10 000 person years, respectively), but the incidence of chest pain attributed to a non-coronary cause remained stable (37-40 per 10 000 person years). Risk of cardiovascular events did not change over time.ConclusionsMost patients with first onset chest pain do not have a diagnosis recorded at presentation or in the subsequent six months, including those who undergo cardiac investigations. These patients have an increased risk of cardiovascular events for at least five years. Efforts to better assess and reduce the cardiovascular risk of such patients are warranted.
authors.affiliation: Arthritis Research UK Primary Care Centre, Research Institute for Primary Care and Health Sciences, Keele University, Keele ST5 5BG, UK k.p.jordan@keele.ac.uk.
authors.forename: Kelvin P
authors.initials: KP
authors.lastname: Jordan
authors.affiliation: NIHR Cardiovascular Biomedical Research Unit, Barts Heart Centre, London, UK.
authors.forename: Adam
authors.initials: A
authors.lastname: Timmis
authors.affiliation: Arthritis Research UK Primary Care Centre, Research Institute for Primary Care and Health Sciences, Keele University, Keele ST5 5BG, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Croft
authors.affiliation: Arthritis Research UK Primary Care Centre, Research Institute for Primary Care and Health Sciences, Keele University, Keele ST5 5BG, UK.
authors.forename: Danielle A
authors.initials: DA
authors.lastname: van der Windt
authors.affiliation: Farr Institute of Health Informatics Research London, Institute of Health Informatics, University College London, London, UK.
authors.forename: Spiros
authors.initials: S
authors.lastname: Denaxas
authors.affiliation: Farr Institute of Health Informatics Research London, Institute of Health Informatics, University College London, London, UK.
authors.forename: Arturo
authors.initials: A
authors.lastname: González-Izquierdo
authors.affiliation: Arthritis Research UK Primary Care Centre, Research Institute for Primary Care and Health Sciences, Keele University, Keele ST5 5BG, UK.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Hayward
authors.affiliation: Centre for Global Non-Communicable Diseases, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Pablo
authors.initials: P
authors.lastname: Perel
authors.affiliation: Farr Institute of Health Informatics Research London, Institute of Health Informatics, University College London, London, UK.
authors.forename: Harry
authors.initials: H
authors.lastname: Hemingway
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000787:Angina Pectoris / Q000175:diagnosis / Q000453:epidemiology; D002318:Cardiovascular Diseases / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology; D002637:Chest Pain / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D015331:Cohort Studies; D057286:Electronic Health Records; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008498:Medical Record Linkage; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000453:epidemiology; D011320:Primary Health Care; D011379:Prognosis; D012042:Registries; D012307:Risk Factors; D006113:United Kingdom / Q000453:epidemiology; D055815:Young Adult