Type and timing of heralding in ST-elevation and non-ST-elevation myocardial infarction: an analysis of prospectively collected electronic healthcare records linked to the national registry of acute coronary syndromes

Lipid Testing Trends Before and After Hospitalization for Myocardial Infarction Among Adults in the United States, 2008-2019

Background

Routine monitoring of low-density lipoprotein cholesterol (LDL-C) identifies patients who may benefit from modifying lipid-lowering therapies (LLT). However, the extent to which LDL-C testing is occurring in clinical practice is unclear, specifically among patients hospitalized for a myocardial infarction (MI).

Methods

Using US commercial claims data, we identified patients with an incident MI hospitalization between 01/01/2008-03/31/2019. LDL-C testing was assessed in the year before admission (pre-MI) and the year after discharge (post-MI). Changes in LDL-C testing were evaluated using a Poisson model fit to pre-MI rates and extrapolated to the post-MI period. We predicted LDL-C testing rates if no MI had occurred (ie, based on pre-MI trends) and estimated rate differences and ratios (contrasting observed vs predicted rates).

Results

Overall, 389,367 patients were hospitalized for their first MI during the study period. In the month following discharge, 9% received LDL-C testing, increasing to 27% at 3 months and 52% at 12 months. Mean rates (tests per 1000 patients per month) in the pre- and post-MI periods were 51.9 (95% CI: 51.7, 52.1) and 84.4 (95% CI: 84.1, 84.6), respectively. Over 12 months post-MI, observed rates were higher than predicted rates; the maximum rate difference was 66 tests per 1000 patients in month 2 (rate ratio 2.2), stabilizing at a difference of 15-20 (ratio 1.2-1.3) for months 6-12.

Conclusion

Although LDL-C testing increased following MI hospitalization, rates remained lower than recommended by clinical guidelines. This highlights a potential gap in care, where increased LDL-C testing after MI may provide opportunities for LLT modification and decrease risk of subsequent cardiovascular events.

Natural language processing for disease phenotyping in UK primary care records for research: a pilot study in myocardial infarction and death

BACKGROUND

Free text in electronic health records (EHR) may contain additional phenotypic information beyond structured (coded) information. For major health events - heart attack and death - there is a lack of studies evaluating the extent to which free text in the primary care record might add information. Our objectives were to describe the contribution of free text in primary care to the recording of information about myocardial infarction (MI), including subtype, left ventricular function, laboratory results and symptoms; and recording of cause of death. We used the CALIBER EHR research platform which contains primary care data from the Clinical Practice Research Datalink (CPRD) linked to hospital admission data, the MINAP registry of acute coronary syndromes and the death registry. In CALIBER we randomly selected 2000 patients with MI and 1800 deaths. We implemented a rule-based natural language engine, the Freetext Matching Algorithm, on site at CPRD to analyse free text in the primary care record without raw data being released to researchers. We analysed text recorded within 90 days before or 90 days after the MI, and on or after the date of death.

RESULTS

We extracted 10,927 diagnoses, 3658 test results, 3313 statements of negation, and 850 suspected diagnoses from the myocardial infarction patients. Inclusion of free text increased the recorded proportion of patients with chest pain in the week prior to MI from 19 to 27%, and differentiated between MI subtypes in a quarter more patients than structured data alone. Cause of death was incompletely recorded in primary care; in 36% the cause was in coded data and in 21% it was in free text. Only 47% of patients had exactly the same cause of death in primary care and the death registry, but this did not differ between coded and free text causes of death.

CONCLUSIONS

Among patients who suffer MI or die, unstructured free text in primary care records contains much information that is potentially useful for research such as symptoms, investigation results and specific diagnoses. Access to large scale unstructured data in electronic health records (millions of patients) might yield important insights.

Big data from electronic health records for early and late translational cardiovascular research: challenges and potential

Aims

Cohorts of millions of people's health records, whole genome sequencing, imaging, sensor, societal and publicly available data present a rapidly expanding digital trace of health. We aimed to critically review, for the first time, the challenges and potential of big data across early and late stages of translational cardiovascular disease research.

Methods and results

We sought exemplars based on literature reviews and expertise across the BigData@Heart Consortium. We identified formidable challenges including: data quality, knowing what data exist, the legal and ethical framework for their use, data sharing, building and maintaining public trust, developing standards for defining disease, developing tools for scalable, replicable science and equipping the clinical and scientific work force with new inter-disciplinary skills. Opportunities claimed for big health record data include: richer profiles of health and disease from birth to death and from the molecular to the societal scale; accelerated understanding of disease causation and progression, discovery of new mechanisms and treatment-relevant disease sub-phenotypes, understanding health and diseases in whole populations and whole health systems and returning actionable feedback loops to improve (and potentially disrupt) existing models of research and care, with greater efficiency. In early translational research we identified exemplars including: discovery of fundamental biological processes e.g. linking exome sequences to lifelong electronic health records (EHR) (e.g. human knockout experiments); drug development: genomic approaches to drug target validation; precision medicine: e.g. DNA integrated into hospital EHR for pre-emptive pharmacogenomics. In late translational research we identified exemplars including: learning health systems with outcome trials integrated into clinical care; citizen driven health with 24/7 multi-parameter patient monitoring to improve outcomes and population-based linkages of multiple EHR sources for higher resolution clinical epidemiology and public health.

Conclusion

High volumes of inherently diverse ('big') EHR data are beginning to disrupt the nature of cardiovascular research and care. Such big data have the potential to improve our understanding of disease causation and classification relevant for early translation and to contribute actionable analytics to improve health and healthcare.

Missed Opportunities in Symptomatic Patients before a First Acute Coronary Syndrome: The EPIHeart Cohort Study

OBJECTIVES

The aim of this study was to assess the proportion of patients with a first episode of acute coronary syndrome (ACS) reporting preceding chest pain, having previously sought medical care and undergone the performance of exams, and to identify the determinants of seeking medical advice and undergoing electrocardiogram (ECG).

METHODS

Within a cohort study, 690 patients with a first episode of ACS were evaluated. A questionnaire was applied to assess chest pain within the preceding 6 months of the event and health system resources utilization. Determinants were identified by logistic regression.

RESULTS

Preceding chest pain was reported by 61% of patients, 43% of these sought medical help, of whom less than half underwent ECG, and in 39% pain was attributed to a problem of the heart. Patients with hypertension were more likely to seek medical care (adjusted odds ratio, OR, 2.13, 95% CI 1.29-3.51), and former smokers (OR 0.52, 95% CI 0.28-0.99) and patients of a higher social class (OR 0.16, 95% CI 0.05-0.48) were less likely to seek medical care. The performance of ECG was associated with male sex (OR 2.56, 95% CI 1.11-5.87), health subsystem coverage (OR 3.88, 95% CI 1.11-13.53), and living in the northeastern region (OR 9.07, 95% CI 4.07-20.24), whereas cognitive impairment (OR 0.37, 95% CI 0.15-0.92) and being employed (OR 0.36, 95% CI 0.14-0.97) were inversely associated.

CONCLUSIONS

These results suggest there are opportunities to improve the diagnosis of myocardial ischemia before acute coronary events.

National Institute for Health and Care Excellence updates the stable chest pain guideline with radical changes to the diagnostic paradigm

In the 2016 update of the stable chest pain guideline, the National Institute for Health and Care Excellence (NICE) has made radical changes to the diagnostic paradigm that it-like other international guidelines-had previously placed at the centre of its recommendations. No longer are quantitative assessments of the disease probability considered necessary to determine the need for diagnostic testing and the choice of test. Instead, the recommendation is for no diagnostic testing if chest pain is judged to be 'non-anginal' and CT coronary angiography (CTCA) in patients with 'typical' or 'atypical' chest pain with additional perfusion imaging only if there is uncertainty about the functional significance of coronary lesions. The new emphasis on anatomical-as opposed to functional-testing is driven in large part by cost-effectiveness analysis and despite inevitable resource implications NICE calculates that annual savings for the population of England will be significant. In making CTCA the default diagnostic testing strategy in its updated chest pain guideline, NICE has responded emphatically to calls from trialists for CTCA to have a greater role in the diagnostic pathway of patients with suspected angina.

Prognosis of undiagnosed chest pain: linked electronic health record cohort study

Objective To ascertain long term cardiovascular outcomes in patients whose chest pain remained undiagnosed six months after first presentation.Design Cohort study.Setting UK electronic health record database (CALIBER) linking primary care, secondary care, coronary registry, and death registry information.Participants 172 180 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 measures Fatal 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.Results At 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.Conclusions Most 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.

Survival prospects after acute myocardial infarction in the UK: a matched cohort study 1987-2011

OBJECTIVES

Estimate survival after acute myocardial infarction (AMI) in the general population aged 60 and over and the effect of recommended treatments.

DESIGN

Cohort study in the UK with routinely collected data between January 1987 and March 2011.

SETTING

310 general practices that contributed to The Health Improvement Network (THIN) database.

PARTICIPANTS

4 cohorts who reached the age of 60, 65, 70, or 75 years between 1987 and 2011 included 16 744, 43 528, 73 728, and 76 392 participants, respectively. Participants with a history of AMI were matched on sex, year of birth, and general practice to 3 controls each.

OUTCOME MEASURES

The hazard of all-cause mortality associated with AMI was calculated by a multilevel Cox's proportional hazards regression, adjusted for sex, year of birth, socioeconomic status, angina, heart failure, other cardiovascular conditions, chronic kidney disease, diabetes, hypertension, hypercholesterolaemia, alcohol consumption, body mass index, smoking status, coronary revascularisation, prescription of β-blockers, ACE inhibitors, calcium-channel blockers, aspirin, or statins, and general practice.

RESULTS

Compared with no history of AMI by age 60, 65, 70, or 75, having had 1 AMI was associated with an adjusted hazard of mortality of 1.80 (95% CI 1.60 to 2.02), 1.71 (1.59 to 1.84), 1.50 (1.42 to 1.59), or 1.45 (1.38 to 1.53), respectively, and having had multiple AMIs with a hazard of 1.92 (1.60 to 2.29), 1.87 (1.68 to 2.07), 1.66 (1.53 to 1.80), or 1.63 (1.51 to 1.76), respectively. Survival was better after statins (HR range across the 4 cohorts 0.74-0.81), β-blockers (0.79-0.85), or coronary revascularisation (in first 5 years) (0.72-0.80); unchanged after calcium-channel blockers (1.00-1.07); and worse after aspirin (1.05-1.10) or ACE inhibitors (1.10-1.25).

CONCLUSIONS

The hazard of death after AMI is less than reported by previous studies, and standard treatments of aspirin or ACE inhibitors prescription may be of little benefit or even cause harm.

Using nationwide ‘big data’ from linked electronic health records to help improve outcomes in cardiovascular diseases: 33 studies using methods from epidemiology, informatics, economics and social science in the ClinicAl disease research using LInked Bespoke studies and Electronic health Records (CALIBER) programme

Background

Electronic health records (EHRs), when linked across primary and secondary care and curated for research use, have the potential to improve our understanding of care quality and outcomes.

Objective

To evaluate new opportunities arising from linked EHRs for improving quality of care and outcomes for patients at risk of or with coronary disease across the patient journey.

Design

Epidemiological cohort, health informatics, health economics and ethnographic approaches were used.

Setting

230 NHS hospitals and 226 general practices in England and Wales.

Participants

Up to 2 million initially healthy adults, 100,000 people with stable coronary artery disease (SCAD) and up to 300,000 patients with acute coronary syndrome.

Main outcome measures

Quality of care, fatal and non-fatal cardiovascular disease (CVD) events.

Data platform and methods

We created a novel research platform [ClinicAl disease research using LInked Bespoke studies and Electronic health Records (CALIBER)] based on linkage of four major sources of EHR data in primary care and national registries. We carried out 33 complementary studies within the CALIBER framework. We developed a web-based clinical decision support system (CDSS) in hospital chest pain clinics. We established a novel consented prognostic clinical cohort of SCAD patients.

Results

CALIBER was successfully established as a valid research platform based on linked EHR data in nearly 2 million adults with > 600 EHR phenotypes implemented on the web portal (seehttps://caliberresearch.org/portal). Despite national guidance, key opportunities for investigation and treatment were missed across the patient journey, resulting in a worse prognosis for patients in the UK compared with patients in health systems in other countries. Our novel, contemporary, high-resolution studies showed heterogeneous associations for CVD risk factors across CVDs. The CDSS did not alter the decision-making behaviour of clinicians in chest pain clinics. Prognostic models using real-world data validly discriminated risk of death and events, and were used in cost-effectiveness decision models.

Conclusions

Emerging ‘big data’ opportunities arising from the linkage of records at different stages of a patient’s journey are vital to the generation of actionable insights into the diagnosis, risk stratification and cost-effective treatment of people at risk of, or with, CVD.

Future work

The vast majority of NHS data remain inaccessible to research and this hampers efforts to improve efficiency and quality of care and to drive innovation. We propose three priority directions for further research. First, there is an urgent need to ‘unlock’ more detailed data within hospitals for the scale of the UK’s 65 million population. Second, there is a need for scaled approaches to using EHRs to design and carry out trials, and interpret the implementation of trial results. Third, large-scale, disease agnostic genetic and biological collections linked to such EHRs are required in order to deliver precision medicine and to innovate discovery.

Study registration

CALIBER studies are registered as follows: study 2 – NCT01569139, study 4 – NCT02176174 and NCT01164371, study 5 – NCT01163513, studies 6 and 7 – NCT01804439, study 8 – NCT02285322, and studies 26–29 – NCT01162187. Optimising the Management of Angina is registered as Current Controlled Trials ISRCTN54381840.

Funding

The National Institute for Health Research (NIHR) Programme Grants for Applied Research programme (RP-PG-0407-10314) (all 33 studies) and additional funding from the Wellcome Trust (study 1), Medical Research Council Partnership grant (study 3), Servier (study 16), NIHR Research Methods Fellowship funding (study 19) and NIHR Research for Patient Benefit (study 33).

Depression as a Risk Factor for the Initial Presentation of Twelve Cardiac, Cerebrovascular, and Peripheral Arterial Diseases: Data Linkage Study of 1.9 Million Women and Men

BACKGROUND

Depression is associated with coronary heart disease and stroke, but associations with a range of pathologically diverse cardiovascular diseases are not well understood. We examine the risk of 12 cardiovascular diseases according to depression status (history or new onset).

METHODS

Cohort study of 1,937,360 adult men and women, free from cardiovascular disease at baseline, using linked UK electronic health records between 1997 and 2010. The exposures were new-onset depression (a new GP diagnosis of depression and/or prescription for antidepressants during a one-year baseline), and history of GP-diagnosed depression before baseline. The primary endpoint was initial presentation of 12 cardiovascular diseases after baseline. We used disease-specific Cox proportional hazards models with multiple imputation adjusting for cardiovascular risk factors (age, sex, socioeconomic status, smoking, blood pressure, diabetes, cholesterol).

RESULTS

Over a median [IQR] 6.9 [2.1-10.5] years of follow-up, 18.9% had a history of depression and 94,432 incident cardiovascular events occurred. After adjustment for cardiovascular risk factors, history of depression was associated with: stable angina (Hazard Ratio = 1.38, 95%CI 1.32-1.45), unstable angina (1.70, 1.60-1.82), myocardial infarction (1.21, 1.16-1.27), unheralded coronary death (1.23, 1.14-1.32), heart failure (1.18, 1.13-1.24), cardiac arrest (1.14, 1.03-1.26), transient ischemic attack (1.31, 1.25-1.38), ischemic stroke (1.26, 1.18-1.34), subarachnoid haemorrhage (1.17, 1.01-1.35), intracerebral haemorrhage (1.30, 1.17-1.45), peripheral arterial disease (1.24, 1.18-1.30), and abdominal aortic aneurysm (1.12,1.01-1.24). New onset depression developed in 2.9% of people, among whom 63,761 cardiovascular events occurred. New onset depression was similarly associated with each of the 12 diseases, with no evidence of stronger associations compared to history of depression. The strength of association between depression and these cardiovascular diseases did not differ between women and men.

CONCLUSION

Depression was prospectively associated with cardiac, cerebrovascular, and peripheral diseases, with no evidence of disease specificity. Further research is needed in understanding the specific pathophysiology of heart and vascular disease triggered by depression in healthy populations.

Long-term prognostic role of cerebrovascular disease and peripheral arterial disease across the spectrum of acute coronary syndromes

BACKGROUND

In acute coronary syndromes (ACS), the influence of cerebro-vascular disease (CVD) and/or peripheral artery disease (PAD) on short-midterm outcome has been well established. Data on long-term outcome however, are limited. Our study aimed to explore the effect of CVD and PAD on long-term outcome in a cohort of unselected ACS patients, including ST-elevation (STE-ACS) and non-ST-elevation (NSTE-ACS).

METHODS AND RESULTS

The population consisted of 2046 consecutive patients with a confirmed final diagnosis of ACS; 896 (44%) had STE-ACS and 1150 (66%) NSTE-ACS. CVD alone was present in 98 patients (5%), 282 (14%) had PAD alone, and 30 (1.5%) had both. All cause mortality at 5 years was lowest in patients without CVD/PAD (33%), intermediate in patients with either CVD or PAD (62% and 63%, respectively) reaching 80% in those with both CVD and PAD. These findings were confirmed in the STE-ACS and NSTE-ACS subgroups. CVD and PAD remained independent predictors of mortality after multivariable analysis, the combined presence of both carrying the highest risk within each ACS type (HR 4.15, 95% CI 1.83-9.44 for STE-ACS; HR 2.14, 1.29-3.54 for NSTE-ACS). Patients with CVD and/or PAD were less likely to be treated invasively and received less evidence-based treatment at discharge.

CONCLUSIONS

Across the spectrum of ACS, extracardiac vascular disease harbors a negative long-term prognosis that worsens progressively with the number of affected arterial beds.

Association between clinical presentations before myocardial infarction and coronary mortality: a prospective population-based study using linked electronic records

Background

Ischaemia in different arterial territories before acute myocardial infarction (AMI) may influence post-AMI outcomes. No studies have evaluated prospectively collected information on ischaemia and its effect on short- and long-term coronary mortality. The objective of this study was to compare patients with and without prospectively measured ischaemic presentations before AMI in terms of infarct characteristics and coronary mortality.

Methods and results

As part of the CALIBER programme, we linked data from primary care, hospital admissions, the national acute coronary syndrome registry and cause-specific mortality to identify patients with first AMI (n = 16,439). We analysed time from AMI to coronary mortality (n = 5283 deaths) using Cox regression (median 2.6 years follow-up), comparing patients with and without recent ischaemic presentations. Patients with ischaemic presentations in the 90 days before AMI experienced lower coronary mortality in the first 7 days after AMI compared with those with no prior ischaemic presentations, after adjusting for age, sex, smoking, diabetes, blood pressure and cardiovascular medications [HR: 0.64 (95% CI: 0.57–0.73) P < 0.001], but subsequent mortality was higher [HR: 1.42 (1.13–1.77) P = 0.001]. Patients with ischaemic presentations closer in time to AMI had the lowest seven day mortality (P-trend = 0.001).

Conclusion

In the first large prospective study of ischaemic presentations prior to AMI, we have shown that those occurring closest to AMI are associated with lower short-term coronary mortality following AMI, which could represent a natural ischaemic preconditioning effect, observed in a clinical setting.

Clinical trials registration

Clinicaltrials.gov identifier NCT01604486.