Elevated chronic bronchitis diagnosis risk among women in a local emergency department patient population associated with the 2012 heatwave and drought in Douglas county, NE USA.

BACKGROUND: Concerns about global climate change force local public health agencies to assess potential local disease risk. OBJECTIVE: Determine if risk of an emergency department chronic bronchitis diagnosis in Douglas County, NE, was higher during the 2012 heatwave compared to the same calendar period in 2011. METHODS: Retrospective, observational, case-control design selecting subjects from 2011 and 2012 emergency department (ED) admissions. Risk was estimated by conditional logistic regression. RESULTS: The odds of an ED chronic bronchitis diagnosis among females was 3.77 (95% CI =1.37-10.21) times higher during the 2012 risk period compared to females admitted to the ED during the 2011 risk period. Chronic bronchitis ED diagnosis odds were 1.05 (95%CI=1.04 - 1.06) times higher for each year of age. ED, gender, and race modified the risk (i.e., effect). The overall chronic bronchitis ED risk estimate was 1.61 (95%CI=0.81 - 3.21) times higher during the 2012 risk period compared to the 2011 risk period. The mean ambient absolute humidity upon admission was 11.44 gr/m3 (95%CI; 10.40 - 12.47) among chronic bronchitis cases and 12.67 gr/m3 (95%CI; 12.63 - 12.71) among controls. CONCLUSION: The odds of ED chronic bronchitis diagnosis was higher among female subjects admitted during the 2012 risk period compared to females admitted during the 2011 risk period.  Age also increased chronic bronchitis ED diagnosis risk among 2012 risk period admissions compared to 2011 risk period admissions.

Emergency department asthma diagnosis risk associated with the 2012 heat wave and drought in Douglas County NE, USA.

BACKGROUND: Global climate change concerns are forcing local public health agencies to assess potential disease risk. OBJECTIVE: Determine if risk of an emergency department asthma diagnosis in Douglas County, NE, was higher during the 2012 heatwave compared to 2011. METHODS: Retrospective, observational, case-control design selecting subjects from 2011 and 2012 emergency department (ED) admissions. Risk was estimated by conditional logistic regression. RESULTS: The asthma ED risk estimate was 1.23 (95%CI = 0.96-1.57) times higher in 2012 than 2011, for the same calendar period. Asthma ED diagnosis risk was 3.37 (95%CI = 2.27-4.17) times higher among subjects <19years old compared to older subjects, and 3.25 (95%CI = 2.63-4.02) times higher among African-Americans than non-African-Americans, adjusted for heatwave exposure. Absolute humidity appears inversely related to asthma diagnosis risk ( χ2 = 16.6; p < 0.001). CONCLUSION: Asthma ED diagnosis risk was not significantly higher in 2012 compared to 2011. Risk was elevated among subjects less than 19years old, and among African Americans; adjusted for heatwave exposure.

The relationship between school absence, academic performance, and asthma status.

BACKGROUND: Children with asthma experience more absenteeism from school compared with their nonasthma peers. Excessive absenteeism is related to lower student grades, psychological, social, and educational adjustment. Less is known about the relationship between the presence of asthma and the academic achievement in school-aged children. Since students with asthma miss more days from school, this may negatively impact their academic achievement. The goal of this study was to investigate the relationships between absenteeism, presence of asthma, and asthma severity level with standardized test level performance in a predominantly African American urban school district. METHODS: A cross-sectional analysis was conducted of 3812 students (aged 8-17 years) who took the Missouri Assessment Program (MAP) standardized test during the 2002-2003 academic year. RESULTS: After adjustment for covariates, a significant inverse relationship was found between absenteeism and test level performance on the MAP standardized test in all children (F = 203.9, p < .001). There was no overall difference in test level achievement between those with and without asthma (p = .12). Though not statistically different, those with persistent asthma showed a modestly increased likelihood of scoring below Nearing Proficient compared with those with mild intermittent asthma (adjusted odds ratio = 1.93, 95% confidence intervals = 0.93-4.01, p = .08). CONCLUSIONS: A negative impact of absenteeism on standardized test level achievement was demonstrated in children from an urban African American school district. Children with asthma perform the same academically as their nonasthma peers. However, those with persistent asthma show a trend of performing worse on MAP standardized test scores and have more absence days compared with other students. More research is warranted on the effects of persistent asthma on academic achievement.

Epidemiology of environmental tobacco smoke exposure.

The health hazards due to exposure to environmental tobacco smoke (ETS) are increasingly established. ETS contains thousands of chemicals including 43 known carcinogens. One of the most important known health effects of ETS exposure is lung cancer in non-smokers, based on epidemiologic evidence and knowledge of the uptake and metabolism of ETS. Epidemiologic studies need to carefully take into account confounding and potential errors in exposure assessment. More research is needed to understand the genetic factors that influence ETS-induced lung cancer. Studies of the patterns of ETS exposure suggest higher rates of exposure in people employed as blue collar workers, in service occupations, earning lower incomes, and among the less educated. Certain racial/ethnic groups (e.g. Blacks, American Indians) may be at higher risk of ETS exposure. Despite substantial progress in protecting individuals from ETS exposure, additional efforts are needed in improving and enforcing policies to reduce exposure.

Micronucleus frequency and proliferation in human lymphocytes after exposure to herbicide 2,4-dichlorophenoxyacetic acid in vitro and in vivo.

Widespread use of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) and its association with non-Hodgkin's lymphoma (NHL) and other cancers has raised public concern. Here, micronucleus (MN) formation has been used as a biomarker of genotoxicity, and replicative and mitotic indices (MIs) as biomarkers of cell cycle kinetics in human lymphocytes. Cells were cultured either as whole blood or isolated lymphocytes and treated with pure or commercial forms of 2,4-D at doses between 0.001 and 1 mM for 48 h. Exposure to 2,4-D produced a minimal increase in MN in whole blood and even smaller one in isolated lymphocyte cultures. This induction took place only at levels approaching cytotoxicity and was accompanied by a significant inhibition of replicative index (RI). At a low (0.005 mM) dose of commercial 2,4-D, a small, marginally significant increase in RI (12-15%) was found in two independent sets of experiments (P=0.052). Additionally, we found that lymphocyte RI was more affected by commercial 2,4-D containing 9.4% of the chemically pure 2,4-D, than with an equal concentration of the latter suggesting that other ingredients present in the commercial pesticide may be responsible or may enhance the effect of 2,4-D. Mitotic index, however, did not show any significant change with either commercial or pure 2,4-D. The lymphocytes of 12 male applicators exposed solely to 2,4-D during a 3-month period had a significantly higher RI than the same group prior to exposure and than a control group (P<0.01), in accordance with the in vitro finding of increased RI at low doses.

Predictors of 2,4-dichlorophenoxyacetic acid exposure among herbicide applicators.

To determine the major factors affecting the urinary levels of 2,4-dichlorophenoxyacetic acid (2,4-D) among county noxious weed applicators in Kansas, we used a regression technique that accounted for multiple days of exposure. We collected 136 12-h urine samples from 31 applicators during the course of two spraying seasons (April to August of 1994 and 1995). Using mixed-effects models, we constructed exposure models that related urinary 2,4-D measurements to weighted self-reported work activities from daily diaries collected over 5 to 7 days before the collection of the urine sample. Our primary weights were based on an earlier pharmacokinetic analysis of turf applicators; however, we examined a series of alternative weighting schemes to assess the impact of the specific weights and the number of days before urine sample collection that were considered. The derived models accounting for multiple days of exposure related to a single urine measurement seemed robust with regard to the exact weights, but less to the number of days considered; albeit the determinants from the primary model could be fitted with marginal losses of fit to the data from the other weighting schemes that considered a different numbers of days. In the primary model, the total time of all activities (spraying, mixing, other activities), spraying method, month of observation, application concentration, and wet gloves were significant determinants of urinary 2,4-D concentration and explained 16% of the between-worker variance and 23% of the within-worker variance of urinary 2,4-D levels. As a large proportion of the variance remained unexplained, further studies should be conducted to try to systematically assess other exposure determinants.

Breast cancer research among African-American women: accurate racial categories?

This essay questions the appropriateness of racial categories in breast cancer research and recommends the discontinuation of "African-American" as a valid racial category in breast cancer research until better categories can be developed.

Existing data on breast cancer in African-American women: what we know and what we need to know.

BACKGROUND: Much of what is known about breast cancer in African-American (AA) women is based on existing cancer surveillance data. Thus, it is important to consider the accuracy of these resources in describing the impact of breast cancer in AA populations. METHODS: National cancer surveillance data bases are described, their most recent findings are presented, their limitations are outlined, and recommendations are made for improving their utility. RESULTS: Breast cancer characteristics have been studied well in urban (but not in rural) and Southern AA populations. The recent Surveillance, Epidemiology, and End Results (SEER) Program expansion and the continued improvement of state cancer registry operations will provide opportunities to study larger and more diverse AA subpopulations. Recommendations for improving the utility of surveillance data bases include adding new items to better describe correlates of advanced stage at diagnosis and reduced survival of AA women with breast cancer by linking surveillance data bases with other large data bases to provide area-level socioeconomic status, health insurance status, and retrieving new information about patient comorbidities and biomarkers from medical records; improving the completeness and accuracy of treatment and survival information already collected for all patients; working to improve the dissemination of appropriate cancer data to nonresearch consumer communities, including clinicians, patients, advocates, politicians, and health officials; and the development of new training programs for cancer registrars and researchers. CONCLUSIONS: The continued improvement of cancer surveillance systems should be considered important activities in this research agenda, because these data will play a far-reaching role in the prevention and control of breast cancer in AA women.