Mortality among military participants at the 1957 PLUMBBOB nuclear weapons test series and from leukemia among participants at the SMOKY test.

Health effects following low doses of ionizing radiation are uncertain. Military veterans at the Nevada test site (NTS) during the SMOKY atmospheric nuclear weapons test in 1957 were reported to be at increased risk for leukemia in 1979, but this increase was not evaluated with respect to radiation dose. The SMOKY test was one of 30 tests in 1957 within the PLUMBBOB test series. These early studies led to public laws where atomic veterans could qualify for compensation for presumptive radiogenic diseases. A retrospective cohort study was conducted of 12219 veterans at the PLUMBBOB test series, including 3020 at the SMOKY nuclear test. Mortality follow-up was through 2010 and observed causes of death were compared with expected causes based on general population rates. Radiation dose to red bone marrow was based on individual dose reconstructions, and Cox proportional hazards models were used to evaluate dose response for all leukemias other than chronic lymphocytic leukemia (non-CLL leukemia). Vital status was determined for 95.3% of the 12 219 veterans. The dose to red bone marrow was low (mean 3.2 mGy, maximum 500 mGy). Military participants at the PLUMBBOB nuclear test series remained relatively healthy after 53 years and died at a lower rate than the general population. In contrast, and in comparison with national rates, the SMOKY participants showed significant increases in all causes of death, respiratory cancer, leukemia, nephritis and nephrosis, and accidents, possibly related in part to lifestyle factors common to enlisted men who made up 81% of the SMOKY cohort. Compared with national rates, a statistically significant excess of non-CLL leukemia was observed among SMOKY participants (Standardized Mortality Ratio = 1.89, 95% 1.24-2.75, n = 27) but not among PLUMBBOB participants after excluding SMOKY (SMR = 0.87, 95% 0.64-1.51, n = 47). Leukemia risk, initially reported to be significantly increased among SMOKY participants, remained elevated, but this risk diminished over time. Despite an intense dose reconstruction, the risk for leukemia was not found to increase with increasing levels of radiation dose to the red bone marrow. Based on a linear model, the estimated excess relative risk per mGy is -0.05 (95% CI -0.14, 0.04). An explanation for the observed excess of leukemia remains unresolved but conceivably could be related to chance due to small numbers, subtle biases in the study design and/or high tobacco use among enlisted men. Larger studies should elucidate further the possible relationship between fallout radiation, leukemia and cancer among atomic veterans.

Significant bronchodilator responsiveness and "reversibility" in a population sample.

Chronic Obstructive Pulmonary Disease (COPD) is defined by being "not fully reversible", most guidelines recommend measurement of lung function after the administration of a bronchodilator. The objective of this study was to compare bronchodilator responsiveness (significant improvement in the FEV(1) or FVC) to full-, partial- or "inverse'" reversibility in obstruction status in a population-based sample in Southeastern Kentucky. The study population was selected using random digit dialing of an adult population in Southeastern Kentucky as part of the Burden of Lung disease (BOLD) project. Lung function was assessed using spirometry pre- and post-bronchodilation. Subjects presence and severity of COPD was classified using modified Global Obstructive Lung Disease (GOLD) criteria. We examined the relation between changes in "obstruction" status (based on the FEV(1)/ FVC of 0.7) and the presence of "significant bronchodilator responsiveness" (based on ≥ 12% improvement in the FEV(1) or the FVC). The final population with acceptable pre- and post-bronchodilator spirometry included 440 participants. 32/440 subjects (7.3%) changed from obstructed to unobstructed (full-reversibility), 19/440 (4.3%) changed from unobstructed to obstructed ("inverse"-reversibility), 389/440 (88.4%) had either no-change or partial-reversibility, and 65/440 (14.8%) had bronchodilator responsiveness. Among those with full-reversibility, only 9/32 (28.1%) had bronchodilator responsiveness, whereas among subjects with "inverse"-reversibility, 10/19 (52.6%) had bronchodilator responsiveness. Among all subjects with bronchodilator responsiveness, only 19/65 (29.2%) changed categories. Our findings suggest that significant bronchodilator responsiveness is not the same as "reversibility" of "obstruction", even though these terms are often used interchangeably.

Testing practices and knowledge of HIV among prenatal care providers in a low seroprevalence state.

As the prevalence of heterosexually transmitted HIV increases among women of childbearing age in the United States, so too does the potential for vertical transmission from mother to child. Early maternal diagnosis and appropriate management are critical to minimizing the risk of perinatal infection. We designed a study to evaluate current prenatal care provider testing practices and knowledge of HIV as it relates to pregnancy in a low seroprevalence state. A written questionnaire was mailed to 642 prenatal care providers in Kentucky. Responses were compared to a similar survey conducted in 1998 and to current federal guidelines for HIV management. Nearly all respondents reported to offer HIV testing to all prenatal patients, demonstrating a marked improvement since 1998 (p < 0.001). However, clinicians did not report adequate follow-up when testing is refused and appear to have limited knowledge of the disease as it relates to pregnancy. Only 9.3% of respondents demonstrated proficiency on two knowledge assessment questions. Those with previous experience treating prenatal patients with HIV were more likely to respond correctly (odds ratio [OR] 3.03; 95% confidence interval [CI] 1.08-8.50). Providers with little experience treating patients with HIV may not possess the basic knowledge required to manage the disease during pregnancy. Additional educational interventions are needed in low seroprevalence areas to ensure the appropriate treatment of all HIV-positive pregnant patients and to minimize the risk of preventable perinatal transmission.