Moshammer en Neuberger concluderen dat de verslechtering van de conditie van de longen een betere voorspeller is van de levensverwachting is dan de kennis over de hoeveelheid asbest waaraan iemand is blootgesteld. Volgens Christensen et al. is er een relatie tussen het aantal asbestvezels dat in de longen aangetroffen wordt en de levensverwachting van een mesothelioompatiënt.
Bron: Moshammer, H. & Neuberger, M. (2008). Lung function predicts survival in a cohort of asbestos cement workers. Int Arch Occup Environ Health. 2008 Apr 12. ABSTRACT
PURPOSE: To study the predictive power of respiratory screening examinations a cohort of asbestos workers was followed from active work in an asbestos cement plant until death.
METHODS: From a cohort with data on individual exposure since first employment 309 workers who had a preventive medical examination in 1989/1990 were observed until death or the end of 2006. The impact of asbestos exposure (fibre years) and of smoking history on lung function was examined by linear regression, on specific causes of death and total mortality by Cox regression. The prognostic value of lung function, chest X-ray, and various clinical findings regarding total mortality was also examined by Cox regression.
RESULTS: Lung function proved to be the best predictor of survival apart from current smoking. Depending on the lung function variable an impairment by the interquartile range resulted in a hazard ratio of 1.5-1.6 while for current smokers it was 2.3. An increase of 70 fibre years (interquartile range) led to a hazard ratio of only 1.1. Lung function was influenced by asbestos exposure, current (but not former) smoking, and by pathological X-ray findings. The risk for pleural mesothelioma was dominated by time since first exposure to crocydolite in the pipe factory while the risk for bronchial cancer increased with smoking and total fibre years. An unexpected finding was an increase of gastric cancer in asbestos cement workers.
CONCLUSION: Lung function decrease predicts risk of premature death better than exposure history and regular spirometry should therefore be offered as primary screening to all former asbestos workers. In workers with a history of high cumulative exposure or rapid lung function decrease or radiological signs (diffuse pleural thickening or small irregular opacities) more sensitive techniques (high resolution computer tomography) need to be applied. All smokers with a history of asbestos exposure should be given free smoking cessation therapy to prevent premature death and lung cancer in particular.
Bron: Christensen, B.C. et. al. (2008). Asbestos burden predicts survival in pleural mesothelioma. Environmental Health Perspectives, Jun;116(6):723-6.
Abstract
Background: Malignant pleural mesothelioma (MPM) is a rapidly fatal asbestos-associated malignancy with a median survival time of <1 year following diagnosis. Treatment strategy is determined in part using known prognostic factors. OBJECTIVE: The aim of this study was to examine the relationship between asbestos exposure and survival outcome in MPM in an effort to advance the understanding of the contribution of asbestos exposure to MPM prognosis. Methods: We studied incident cases of MPM patients enrolled through the International Mesothelioma Program at Brigham and Women's Hospital in Boston, Massachusetts, using survival follow-up, self-reported asbestos exposure (n=128), and a subset of cases (n=80) with quantitative asbestos fiber burden measures. Results: Consistent with the established literature, we found independent, significant associations between male sex and reduced survival (p<0.04), as well as between nonepithelioid tumor histology and reduced survival (p<0.02). Although self-reported exposure to asbestos was not predictive of survival among our cases, stratifying quantitative asbestos fiber burden [number of asbestos bodies per gram of lung (wet weight)] into groups of low (0-99 asbestos bodies), moderate (100-1,099), and high fiber burden (>1,099), suggested a survival duration association among these groups (p=0.06). After adjusting for covariates in a Cox model, we found that patients with a low asbestos burden had a 3-fold elevated risk of death compared to patients with a moderate fiber burden [95% confidence interval (CI), 0.95-9.5; p=0.06], and patients with a high asbestos burden had a 4.8-fold elevated risk of death (95% CI, 1.5-15.0; p<0.01) versus those with moderate exposure. Conclusion: Our data suggest that patient survival is associated with asbestos fiber burden in MPM and is perhaps modified by susceptibility.