Acute myocardial infarction: a comparison of short-term survival in national outcome registries in Sweden and the UK.
BACKGROUND
International research for acute myocardial infarction lacks comparisons of whole health systems. We assessed time trends for care and outcomes in Sweden and the UK.


METHODS
We used data from national registries on consecutive patients registered between 2004 and 2010 in all hospitals providing care for acute coronary syndrome in Sweden and the UK. The primary outcome was all-cause mortality 30 days after admission. We compared effectiveness of treatment by indirect casemix standardisation. This study is registered with ClinicalTrials.gov, number NCT01359033.


RESULTS
We assessed data for 119,786 patients in Sweden and 391,077 in the UK. 30-day mortality was 7·6% (95% CI 7·4-7·7) in Sweden and 10·5% (10·4-10·6) in the UK. Mortality was higher in the UK in clinically relevant subgroups defined by troponin concentration, ST-segment elevation, age, sex, heart rate, systolic blood pressure, diabetes mellitus status, and smoking status. In Sweden, compared with the UK, there was earlier and more extensive uptake of primary percutaneous coronary intervention (59% vs 22%) and more frequent use of β blockers at discharge (89% vs 78%). After casemix standardisation the 30-day mortality ratio for UK versus Sweden was 1·37 (95% CI 1·30-1·45), which corresponds to 11,263 (95% CI 9620-12,827) excess deaths, but did decline over time (from 1·47, 95% CI 1·38-1·58 in 2004 to 1·20, 1·12-1·29 in 2010; p=0·01).


CONCLUSIONS
We found clinically important differences between countries in acute myocardial infarction care and outcomes. International comparisons research might help to improve health systems and prevent deaths.


BACKGROUND
Seventh Framework Programme for Research, National Institute for Health Research, Wellcome Trust (UK), Swedish Association of Local Authorities and Regions, Swedish Heart-Lung Foundation.
Farr Institute of Health Informatics Research at UCL Partners, University College London, London, UK.
Sheng-Chia
SC
Chung
Uppsala Clinical Research Centre, Uppsala University, Uppsala, Sweden.
Rolf
R
Gedeborg
National Institute for Clinical Outcomes Research, University College London, London, UK.
Owen
O
Nicholas
Uppsala Clinical Research Centre, Uppsala University, Uppsala, Sweden; Department of Medical Sciences, Cardiology, Uppsala University, Uppsala, Sweden.
Stefan
S
James
Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Gothenburg, Sweden.
Anders
A
Jeppsson
Division of Health and Social Care Research, King's College London, London, UK; National Institute of Health Research Comprehensive Biomedical Research Centre, Guy's & St Thomas' NHS Foundation Trust and King's College London, London, UK.
Charles
C
Wolfe
Institute for Clinical Epidemiology and Biometry and Comprehensive Heart Failure Centre, University of Würzburg, Würzburg, Germany.
Peter
P
Heuschmann
Uppsala Clinical Research Centre, Uppsala University, Uppsala, Sweden; Department of Medical Sciences, Cardiology, Uppsala University, Uppsala, Sweden.
Lars
L
Wallentin
Centre for Cardiovascular Prevention and Outcomes, University College London, London, UK.
John
J
Deanfield
National Institute for Health Research, Biomedical Research Unit, Bart's Health London, London, UK.
Adam
A
Timmis
Department of Medicine, Huddinge, Section of Cardiology, Karolinska Institute, Stockholm, Sweden. Electronic address: tomas.jernberg@karolinska.se.
Tomas
T
Jernberg
Farr Institute of Health Informatics Research at UCL Partners, University College London, London, UK. Electronic address: h.hemingway@ucl.ac.uk.
Harry
H
Hemingway
D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000401:mortality* / Q000628:therapy; D012042:Registries; D012307:Risk Factors; D016019:Survival Analysis; D013548:Sweden / Q000453:epidemiology; D006113:United Kingdom / Q000453:epidemiology