Risk of invasive pneumococcal disease in people admitted to hospital with selected immune-mediated diseases: record linkage cohort analyses
- Correspondence to Professor Michael J Goldacre, Unit of Health-Care Epidemiology, Department of Public Health, University of Oxford, Old Road Campus, Oxford OX3 7LF, UK;
Contributors MJG designed the study. CJW undertook the analyses. CJW and MJG contributed to the interpretation and discussion of findings. CJW wrote the first draft and MJG contributed to the final manuscript.
- Accepted 5 March 2012
- Published Online First 6 April 2012
Background Invasive pneumococcal disease is a serious infection, and it is an important cause of morbidity and mortality in certain groups of ‘at-risk’ people. Those considered ‘at-risk’ in the UK include very young children, people aged 65 years and older and people with certain serious chronic diseases, asplenia or immunosuppression. There is little evidence about whether people with immune-mediated diseases are at increased risk of pneumococcal disease and therefore may benefit from pneumococcal vaccination.
Methods Retrospective cohort studies, using linked hospital data, from the longstanding Oxford Record Linkage Study (1963–2008) and from recent English national linked Hospital Episode Statistics (1999–2008); analysis of whether people with immune-mediated diseases are more likely than others to be admitted to hospital for pneumococcal disease; calculation of rate ratio for pneumococcal disease in cohorts with immune-mediated disease compared with control cohorts.
Results There were elevated rate ratios for many of the immune-mediated diseases, for example, Addison's disease in England 3.8 (95% CI 3.4 to 4.2), autoimmune haemolytic anaemia 4.9 (4.4 to 5.3), Crohn's disease 2.2 (2.1 to 2.3), diabetes mellitus 3.7 (3.4 to 4.1), multiple sclerosis 3.7 (3.5 to 3.8), myxoedema 1.60 (1.58 to 1.63), pernicious anaemia 1.74 (1.66 to 1.83), primary biliary cirrhosis 3.3 (2.9 to 3.7), polyarteritis nodosa 5.0 (4.0 to 6.0), rheumatoid arthritis 2.47 (2.41 to 2.52), scleroderma 4.2 (3.8 to 4.7), Sjogren's syndrome 3.2 (2.9 to 3.5) and systemic lupus erythematosus 5.0 (4.6 to 5.4). Findings in the Oxford and all England data sets were similar.
Conclusions People admitted to hospital with immune-mediated diseases are at higher risk than those with invasive pneumococcal disease. Vaccination should be considered in this group of patients.
- Invasive pneumococcal disease
- multiple sclerosis
- systemic lupus erythematosus
- immune-mediated disease
- record linkage
- public health
- public health policy
- health services
- access to healthcare
Funding The Unit of Health-Care Epidemiology is funded by the English National Institute for Health Research to analyse the linked data. The views expressed in this paper do not necessarily reflect those of the funding body.
Competing interests None.
Ethics approval Ethical approval for analysis of the record linkage study data was obtained from the Central and South Bristol Multi-Centre Research Ethics Committee (04/Q2006/176).
Provenance and peer review Not commissioned; externally peer reviewed.