Low Dose Ionizing Radiation and Cancer Mortality Among Enlisted Men Stationed on Nuclear-Powered Submarines in the United States Navy

s / Annals of Epidemiology 24 (2014) 682e702 687 Conclusions: Men who serve on nuclear-powered submarines are selected to be healthier than the general public and have lower mortality rates for nearly all causes of death. The excess suicide among menwith short duration of service on nuclear-powered submarines is notable. The increasing trend of mortality from ischemic heart disease with duration of submarine duty may reflect, in part, an effect of environmental tobacco smoke, although confounding by individual tobacco smoking cannot be excluded. P19. Low Dose Ionizing Radiation and Cancer Mortality Among Enlisted Men Stationed on Nuclear-Powered Submarines in the United States Navy George Friedman-Jimenez MD, DrPH, Ikuko Kato MD, PhD, Yelena Afanasyeva MS, Roy E. Shore PhD, DrPH. NYU School of Medicine Purpose: Men stationed on nuclear-powered submarines are occupationally exposed to external ionizing radiation at very low levels. Radiation dose for each individual is closely monitored. Little is known about the cancer mortality experience of this group. Methods: This historical cohort study followed 85,033 enlisted men who served on nuclear-powered submarines in the U.S. Navy between 1969 and 1982 to determine patterns of cancer mortality. Occupational radiation doses were measured by badge dosimeters for each individual for all periods of Navy service potentially involving radiation exposure. Deaths were ascertained through searches of multiple national mortality databases. Within-cohort dose-response relationships were estimated using linear and loglinear Poisson regression models to adjust for multiple confounders. Results: A total of 584 cancer deaths occurred in 1,805,581 person years (up to 27 years) of follow-up. The mean occupational radiation dose received while in the Navy was 5.7 millisieverts (mSv). Excess Relative Risks per 10 mSv and 95% Confidence Intervals are 0.052(-0.03,0.18) for all solid cancers, 0.003(-0.29,0.30) for leukemias excluding chronic lymphocytic leukemia, 0.052(-0.07,0.17) for cancers previously associated with smoking, and 0.012 (-0.10,0.12) for cancers not previously associated with smoking. The 95 percent Confidence Intervals include the null value for all cause-of-death categories analyzed. Conclusions: The Excess Relative Risk and Relative Risk point estimates for most cancers are similar to those reported in previous published studies, however, the 95% Confidence Intervals are wide. Confounding of these estimates by tobacco smoking cannot be excluded for cancers that are associated with smoking. P20. Association Between Work-Related Discrimination and Low Back Pain Among Korean Employees: Role of Labor Union Status as an Effect Modifier Hyoju Sung, Seung-Sup Kim ScD. Korea University Purpose: To investigate the association between work-related discrimination (WRD) and low back pain (LBP) and to explore the role of labor union as an effect modifier. Methods: We analyzed 29,608 employees from the 3rd wave of Korean Working Condition Survey (2011). WRDs from five different reasons were assessed using questions: “Have you ever experienced work-related discrimination during the past 12 months based on your: (1) age, (2) education, (3) birth region, (4) sex, and (5) employment status?” Labor union status was assessed in three categories: (1) employees in a workplace without labor union, (2) employees did not have a union membership in a workplace with labor union, and (3) employees had union membership. Results: In a workplace without labor union, LBP was significantly associated with WRD based on age (OR: 2.08, 95% CI: 1.69, 2.55), education (OR: 1.31, 95% CI: 1.04, 1.64), birth region (OR: 1.44, 95% CI: 1.02, 2.05), sex (OR: 2.89, 95% CI: 2.18, 3.84), and employment status (OR: 2.03, 95% CI: 1.64, 2.51) among female employees after controlling covariates including self-reported ergonomic strains. Similar significant associations were observed among male employees except WRD based on birth region (OR: 1.37, 95% CI: 0.95, 1.97). However, no significant association was observed for both male and female employee in a workplace with labor union regardless of whether or not employee had union membership except sex discrimination among female employees with union membership (OR: 3.77, 95% CI: 1.45, 9.83). Conclusions: WRD was associated with LBP only in workplaces without labor union. P21. Police Stress and Posttraumatic Stress Disorder: The Role of Coping Claudia C. Ma MS, MPH, Michael E. Andrew PhD, Anna Mnatsakanova MS, Tara A. Hartley PhD, Desta Fekedulegn PhD, Erin McCanlies PhD, Ja K. Gu MSPH, John M. Violanti PhD, Cecil M. Burchfiel PhD. NIOSH Purpose: We investigated the cross-sectional associations between police stress and posttraumatic stress disorder (PTSD) symptoms, and the role of coping. Methods: A total score from PTSD Checklist-Civilian Version (PCL-C), a 17item self-report questionnaire, was used for PTSD assessment in 342 officers. Job stress was assessed using the 60-item Spielberger Police Stress Survey. Mean stress indices were computed by averaging the products of the stress rating (0-100) and frequency (events occurring in the previous year to the date of examination) for total and stress subscales including administrative pressure, physical/psychological threats, and lack of support. Active and passive coping scores were derived from the Brief COPE. Simple and multiple linear regression models were used in the analyses. Results: PTSD symptoms were positively associated with total stress (B1⁄40.016, p 75th percentiles). Relative risk (RR) and 95% confidence limits (CI) were calculated using generalized linear models adjusting for site, age, race, and diabetes. Interactions between pollutants and maternal asthma were explored. Results: Preeclampsia was not associated with air pollutants in nulliparas except for a protective effect of ozone observed for themid-range of exposure (25th -75th percentile) compared to the lowest quartile (reference), RR1⁄40.9907, 95% CI: 0.9858, 0.9956. Asthma was associated with a small increased risk (w1%) in all models. Significant interactions with maternal asthmawere observed for PM10 andNOx. Pollutant effect sizes for asthmatics were often greater but not significantly different from non-asthmatics. Conclusion: Air pollutants did not appear to increase preeclampsia beyond the risk associated with nulliparity. Asthma independently increased risk but without substantive interaction with exposure. P23. Disaster-Related Exposures and Health Effects Among U.S. Coast Guard Responders to Hurricanes Katrina and Rita: A Cross-Sectional Study Jennifer Rusiecki PhD, Dana L. Thomas MD, MPH, Ligong Chen MD, MS, Renee Funk DVM, MPH&TM, Jodi McKibben PhD, Melburn R. Dayton MPH. Uniformed Services University