Mortality among British asbestos workers undergoing regular medical examinations (1971–2005)
- 1 Health and Safety Laboratory, Buxton, Derbyshire, UK
- 2 Health and Safety Executive, Bootle, Merseyside, UK
- 3 Department of Epidemiology and Genetics, Westlakes Research Institute, Moor Row, Cumbria, UK
- 4 Faculty of Health and Social Care, University of Central Lancashire, Preston, Lancashire, UK
- A-H Harding, Health and Safety Laboratory, Harpur Hill, Buxton, Derbyshire SK17 6RN, UK;
- Accepted 7 February 2009
- Published Online First 1 March 2009
Objectives: The Great Britain Asbestos Survey was established to monitor mortality among workers covered by regulations to control occupational exposure to asbestos. This study updates the estimated burden of asbestos-related mortality in the cohort, and identifies risk factors associated with mortality.
Methods: From 1971, workers were recruited during initially voluntary and later statutory medical examinations. A brief questionnaire was completed during the medical, and participants were flagged for death registrations. Standardised mortality ratios (SMRs) and proportional mortality ratios (PMRs) were calculated for deaths occurring before 2006. Poisson regression analyses were undertaken for diseases with significant excess mortality.
Results: There were 15 496 deaths among 98 117 workers followed-up for 1 779 580 person-years. The SMR for all cause mortality was 141 (95% CI 139 to 143) and for all malignant neoplasms 163 (95% CI 159 to 167). The SMRs for cancers of the stomach (166), lung (187), peritoneum (3730) and pleura (968), mesothelioma (513), cerebrovascular disease (164) and asbestosis (5594) were statistically significantly elevated, as were the corresponding PMRs. In age and sex adjusted analysis, birth cohort, age at first exposure, year of first exposure, duration of exposure, latency and job type were associated with the relative risk of lung, pleural and peritoneal cancers, asbestosis and mesothelioma mortality.
Conclusions: Known associations between asbestos exposure and mortality from lung, peritoneal and pleural cancers, mesothelioma and asbestosis were confirmed, and evidence of associations with stroke and stomach cancer mortality was observed. Limited evidence suggested that asbestos-related disease risk may be lower among those first exposed in more recent times.
Competing interests: None.
Funding: The Health and Safety Executive funded the study.
Authors’ contributions: JW and A-HH had full access to the study data and take responsibility for the integrity of the data. A-HH, AD and DM conceptualised this analysis. A-HH was responsible for the data analysis, data interpretation and the first draft of the manuscript. All authors contributed to subsequent drafts, and have seen and approved the final version.
Ethics approval: This study was approved by the British Medical Association Research Ethics Committee.