PT - JOURNAL ARTICLE AU - Hart, J E AU - Laden, F AU - Eisen, E A AU - Smith, T J AU - Garshick, E 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.