Deaths certified as asthma and use of medical services: a national case-control study
- P M Sturdy2,
- B K Butland1,
- H R Anderson1,
- J G Ayres3,
- J M Bland4,
- B D W Harrison5,
- C Peckitt6,
- C R Victor7,
- on behalf of the National Asthma Campaign Mortality and Severe Morbidity Group
- 1Division of Public Health Sciences, St George’s, London SW17 0RE, UK
- 2Institute of Community Health Sciences, Barts and the London, Queen Mary’s School of Medicine and Dentistry, London, UK
- 3Department of Environmental and Occupational Medicine, Liberty Safe Work Research Centre, University of Aberdeen, UK
- 4Department of Health Sciences, University of York, York, UK
- 5Department of Respiratory Medicine, Norfolk and Norwich University Hospital NHS Trust, Norfolk, UK
- 6Institute of Cancer, University of London, UK
- 7Professor of Gerontology and Health Services Research, Head of School of Health and Social Care, University of Reading, UK
- Correspondence to:
Professor H R Anderson
Division of Community Health Sciences, St George’s, University of London, London SW17 0RE, UK;
- Received 25 March 2004
- Accepted 14 July 2005
- Published Online First 29 July 2005
Background: Studies have linked asthma death to either increased or decreased use of medical services.
Methods: A population based case-control study of asthma deaths in 1994–8 was performed in 22 English, six Scottish, and five Welsh health authorities/boards. All 681 subjects who died were under the age of 65 years with asthma in Part I on the death certificates. After exclusions, 532 hospital controls were matched to 532 cases for age, district, and date of asthma admission/death. Data were extracted blind from primary care records.
Results: The median age of the subjects who died was 53 years; 60% of cases and 64% of controls were female. There was little difference in outpatient attendance (55% and 55%), hospital admission for asthma (51% and 54%), and median inpatient days (20 days and 15 days) in the previous 5 years. After mutual adjustment and adjustment for sex, using conditional logistic regression, three variables were independently associated with asthma death: fewer general practice contacts (odds ratio 0.82 (95% confidence interval (CI) 0.74 to 0.91) per 5 contacts) in the previous year, more home visits (1.14 (95% CI 1.08 to 1.21) per visit) in the previous year, and fewer peak expiratory flow recordings (0.83 (95% CI 0.74 to 0.92) per occasion) in the previous 3 months. These associations were similar after adjustment for markers of severity, psychosocial factors, systemic steroids, short acting bronchodilators and antibiotics, although the association with peak flow was weakened and just lost significance.
Conclusion: Asthma death is associated with less use of primary care services. Both practice and patient factors may be involved and a better understanding of these may offer possibilities for reducing asthma death.
This study was funded jointly between the National Research and Development Asthma Management Programme (contract number AM1/05/002) and the National Asthma Campaign through a grant from Glaxo Wellcome (now GlaxoSmithKline).
Competing interests: none declared
Patricia Sturdy was responsible for coordinating the study, undertaking field work, data extraction and drafting the paper. Barbara Butland supervised and contributed to the statistical analyses, advised on interpretation and undertook drafting. Ross Anderson, as the principal investigator, designed and supervised the whole project and contributed to the drafting. Jon Ayres and Brian Harrison helped design the study, undertook validation, and contributed to drafting. Martin Bland was partly responsible for the design of the study and for the statistical analysis and interpretation. Clare Peckitt carried out the statistical analysis. Christina Victor advised on study design.
Published Online First 29 July 2005