PT  - JOURNAL ARTICLE
AU  - J E Hart
AU  - F Laden
AU  - E A Eisen
AU  - T J Smith
AU  - E Garshick
TI  - Chronic obstructive pulmonary disease mortality in railroad workers
AID  - 10.1136/oem.2008.040493
DP  - 2009 Apr 01
TA  - Occupational and Environmental Medicine
PG  - 221--226
VI  - 66
IP  - 4
4099  - http://oem.bmj.com/content/66/4/221.short
4100  - http://oem.bmj.com/content/66/4/221.full
SO  - Occup Environ Med2009 Apr 01; 66
AB  - Background: There is little information describing the risk of non-malignant respiratory disease and occupational exposure to diesel exhaust.Methods: US railroad workers have been exposed to diesel exhaust since diesel locomotives were introduced after World War II. In a retrospective cohort study we examined the association of chronic obstructive pulmonary disease (COPD) mortality with years of work in diesel-exposed jobs. To examine the possible confounding effects of smoking, multiple imputation was used to model smoking history. A Cox proportional hazards model was used to estimate an incidence rate ratio, adjusted for age, calendar year, and length of follow-up after leaving work (to reduce bias due to a healthy worker survivor effect).Results: Workers in jobs with diesel exhaust exposure had an increased risk of COPD mortality relative to those in unexposed jobs. Workers hired after the introduction of diesel locomotives had a 2.5% increase in COPD mortality risk for each additional year of work in a diesel-exposed job. This risk was only slightly attenuated after adjustment for imputed smoking history.Conclusions: These results support an association between occupational exposure to diesel exhaust and COPD mortality.