Judith R. Rager

Fine particulate matter and the risk of autism spectrum disorder

The causes of autism spectrum disorder (ASD) are not well known. Recent investigations have suggested that air pollution, including PM2.5, may play a role in the onset of this condition. The objective of the present work was to investigate the association between prenatal and early childhood exposure to fine particulate matter (PM2.5) and risk for childhood ASD. A population-based case-control study was conducted in children born between January 1, 2005 and December 31, 2009 in six counties in Southwestern Pennsylvania. ASD cases were recruited from specialty autism clinics, local pediatric practices, and school-based special needs services. ASD cases were children who scored 15 or above on the Social Communication Questionnaire (SCQ) and had written documentation of an ASD diagnosis. Controls were children without ASD recruited from a random sample of births from the Pennsylvania state birth registry and frequency matched to cases on birth year, gender, and race. A total of 217 cases and 226 controls were interviewed. A land use regression (LUR) model was used to create person- and time-specific PM2.5 estimates for individual (pre-pregnancy, trimesters one through three, pregnancy, years one and two of life) and cumulative (starting from pre-pregnancy) key developmental time periods. Logistic regression was used to investigate the association between estimated exposure to PM2.5 during key developmental time periods and risk of ASD, adjusting for mothers age, education, race, and smoking. Adjusted odds ratios (AOR) were elevated for specific pregnancy and postnatal intervals (pre-pregnancy, pregnancy, and year one), and postnatal year two was significant, (AOR=1.45, 95% CI=1.01-2.08). We also examined the effect of cumulative pregnancy periods; noting that starting with pre-pregnancy through pregnancy, the adjusted odds ratios are in the 1.46-1.51 range and significant for pre-pregnancy through year 2 (OR=1.51, 95% CI=1.01-2.26). Our data indicate that both prenatal and postnatal exposures to PM2.5 are associated with increased risk of ASD. Future research should include multiple pollutant models and the elucidation of the biological mechanism for PM2.5 and ASD.

The Relationship of Ambient Ozone and PM 2.5 Levels and Asthma Emergency Department Visits: Possible Influence of Gender and Ethnicity

ABSTRACT An investigation of the relationship of air pollution and emergency department (ED) visits for asthma was an opportunity to assess environmental risks for asthma exacerbations in an urban population. A total of 6,979 individuals with a primary discharge diagnosis of asthma presented to 1 of 6 EDs in the Pittsburgh, Pennsylvania, area between 2002 and 2005. Using a case-crossover methodology, which controls for the effects of subject-specific covariates such as gender and race, a 2.5% increase was observed in asthma ED visits for each 10 ppb increase in the 1-hour maximum ozone level on day 2 (odds ratio [OR] = 1.025, p < .05). Particulate matter with an aerodynamic diameter ≤2.5 μm (PM2.5) had an effect both on the total population on day 1 after exposure (1.036, p < .05), and on African Americans on days 1, 2, and 3. PM2.5 had no significant effect on Caucasian Americans alone. The disparity in risk estimates by race may reflect differences in residential characteristics, exposure to ambient air pollution, or a differential effect of pollution by race.

A case-crossover analysis of the impact of PM2.5 on cardiovascular disease hospitalizations for selected CDC tracking states

BACKGROUND Information is currently being collected by the CDC Environmental Public Health Tracking (EPHT) network on hospitalizations due to Acute Myocardial Infarction (AMI) and there is interest by CDC in exploring the relationship between fine particulate matter (PM2.5) and other cardiovascular (CVD) outcomes in the context of the EPHT program. The goal of this study was to assess the short term effects of daily PM(2.5) air pollution levels on hospitalizations for CVD for seven states within the CDC EPHT network (Florida, Massachusetts, New Hampshire, New Jersey, New Mexico, New York, and Washington). METHODS Hospitalization data was obtained for 2001-2008 admissions for circulatory disease (primary discharge diagnosis of ICD-9 codes 390-459) from data stewards in those states and included admission date, age, gender, and zip code of residence. We used CMAQ-derived predicted daily PM2.5 data as estimated by EPA at the centroid of each Census Bureau Zip Code Tabulation Area (ZCTA) and linked to zip code of patient residence. A time-stratified case-crossover study design with conditional logistic regression was used to evaluate the short-term association of PM2.5 on risk of non-elective hospitalizations for CVD. Specifically, we considered all circulatory disease, ischemic heart disease, acute myocardial infarction, heart failure, cardiac arrhythmia, cerebrovascular disease and peripheral vascular disease endpoints. RESULTS Data were obtained on over 7,500,000 hospitalizations for this time period. Mean annual PM2.5 exposure levels were lowest for New Mexico and Washington (6.5 μg/m3 PM2.5 and 8.4 μg/m3 PM2.5). New Jersey, New York and Massachusetts exhibited the highest annual averages for PM2.5, (12.8 μg/m3, 11.1 μg/m3 and 10.8 μg/m3), respectively. The Northeast states (Massachusetts, New Jersey, New Hampshire and New York) exhibited significant effects of PM2.5 during the cooler months across most disease categories after adjustment for ozone and maximum apparent temperature. Ischemic heart disease risk per 10 μg/m3 increase in PM2.5 varied from 1.02 to 1.05 for the cooler months. The largest lag effect was noted on lag days 0 and 1. New Mexico and Washington exhibited no cool or warm month significant effects. Although Florida showed no cooler month effects, significant increases were noted in odds ratios for the warm weather months for all outcomes except peripheral vascular disease. This study is one of the first large scale applications of linkage of hospitalization data by state with national US EPA statistically modeled air pollution data. The results demonstrate that state-wide, there are multiple cardiovascular outcomes in addition to AMI which may be impacted by particulate air pollution.

Association of exposure to particulate matter (PM2.5) air pollution and biomarkers of cardiovascular disease risk in adult NHANES participants (2001–2008)

BACKGROUND AND OBJECTIVES Exposure to particulate matter (PM2.5) has been associated with increased cardiovascular outcomes, mediated by a hypothesized biological mechanism of systemic inflammation and oxidation. Although PM10 has been linked to inflammatory markers in a nationally representative sample (NHANES) using data from earlier cycles (1989-1994); no study has considered these relationships for PM2.5 in more recent time periods. We examined the association of ambient PM2.5 exposure and inflammatory markers in adult NHANES participants for cycles 2001-2008. METHODS We linked each of the adult NHANES participants address with meteorological and modeled air pollution data for each census tract in conterminous United States. The effects of short and long term PM2.5 on C-reactive protein, white blood cells, fibrinogen and homocysteine were analyzed using multiple linear regression, adjusting for cardiovascular risk factors, temperature and ozone. SAS SURVEYREG was used to account for the complex survey design of NHANES. RESULTS In the overall population, no significant positive associations were noted for either short or long term PM2.5 exposures for any of the biomarkers after controlling for confounders. However, stronger associations were found among obese, diabetics, hypertensive and smokers. For every 10μg/m(3) increase in PM2.5, there was an increase of (a) 36.9% (95% CI: 0.1%, 87.2%) in CRP at annual average PM2.5 (adjusting for short term exposure) among diabetics (b) 2.6% (95% CI: 0.1%, 5.1%) in homocysteine at lag 0 among smokers. CONCLUSIONS In a nationally representative sample of individuals we noted no overall association between PM2.5 and biomarkers of cardiovascular risk. However, sensitive subgroups manifested increases in these markers to PM2.5 exposure. Further studies should concentrate on the impact of PM2.5 on these biomarkers in those with multiple cardiovascular risk factors.

Trends in Acute Myocardial Infarction Hospitalization Rates for US States in the CDC Tracking Network

Objectives We examined temporal trends, spatial variation, and gender differences in rates of hospitalization due to acute myocardial infarction. Methods We used data from the Centers for Disease Control National Environmental Public Health Tracking Network to evaluate temporal trends, geographic variation, and gender differences in 20 Environmental Public Health Tracking Network states from 2000 to 2008. A longitudinal linear mixed effects model was fitted to the acute myocardial infarction hospitalization rates for the states and counties within each state to examine the overall temporal trend. Results There was a significant overall decrease in age-adjusted acute myocardial infarction hospitalization rates between 2000 and 2008, with most states showing over a 20% decline during the period. The ratio of male/female rates for acute myocardial infarction hospitalization rates remained relatively consistent over time, approximately two-fold higher in men compared to women. A large geographic variability was found for age-adjusted acute myocardial infarction hospitalization rates, with the highest rates found in the Northeastern states. Results of two ecological analyses revealed that the NE region remained significantly associated with increased AMI hospitalization rates after adjustment for socio-demographic factors. Conclusions This investigation is one of the first to explore geographic differences in AMI age adjusted hospital rates in individuals 35+ years of age for 2000–2008. We showed a decreasing trend in AMI hospitalization rates in men and women. A large geographic variability in rates was found with particularly higher rates in the New England/Mid-Atlantic region of the US and lower rates in the mountain and Pacific states of the tracking network. It appeared that over time this disparity in rates became less notable.

Do US Ambient Air Lead Levels Have a Significant Impact on Childhood Blood Lead Levels: Results of a National Study

Introduction. Although lead paint and leaded gasoline have not been used in the US for thirty years, thousands of US children continue to have blood lead levels (BLLs) of concern. Methods. We investigated the potential association of modeled air lead levels and BLLs ≥ 10 μg/dL using a large CDC database with BLLs on children aged 0–3 years. Percent of children with BLLs ≥ 10 μg/dL (2000–2007) by county and proportion of pre-50 housing and SES variables were merged with the US EPAs National Air Toxics Assessment (NATA) modeled air lead data. Results. The proportion with BLL ≥ 10 μg/dL was 1.24% in the highest air lead counties, and the proportion with BLL ≥ 10 μg/dL was 0.36% in the lowest air lead counties, resulting in a crude prevalence ratio of 3.4. Further analysis using multivariate negative binomial regression revealed that NATA lead was a significant predictor of % BLL ≥ 10 μg/dL after controlling for percent pre-l950 housing, percent rural, and percent black. A geospatial regression revealed that air lead, percent older housing, and poverty were all significant predictors of % BLL ≥ 10 μg/dL. Conclusions. More emphasis should be given to potential sources of ambient air lead near residential areas.

Cigarette smoking and the risk of adult leukemia: results from the Three Mile Island cohort study.

Smoking is an unconfirmed risk factor for the development of leukemia. The authors examined the potential link using data from the Three Mile Island cohort for the period 1979-1995. Eligible for analysis were 24,539 individuals aged 14 years or older who were followed up over 16 years from the Three Mile Island cohort. The authors identified all incident leukemia cases through the Pennsylvania Department of Health Cancer Registry. They used the Cox proportional hazards model to evaluate the relationships and observed 42 incident leukemia cases, including 15 acute myeloid leukemia (AML) cases, in the cohort. After controlling for other confounding factors, the authors found current smoking to be associated with an increased risk of adult AML (relative risk = 3.47; 95% confidence interval = 1.002-11.99). The authors also observed a marginally significant linear trend of risk of AML associated with the number of years smoked (p = .06). The results from this study suggested that cigarette smoking was associated with an increased risk of adult AML. Further investigation is required to confirm these findings.

Using spatio-temporal modeling for exposure assessment in an investigation of fine particulate air pollution and cardiovascular mortality.

BACKGROUND U.S. urban air quality has improved dramatically over the past decades. We evaluated acute effects of fine particulate matter (PM2.5) on cardiovascular (CVD) mortality among residents of Allegheny County in SW Pennsylvania (1999-2011) using spatio-temporal modeling of air pollutants (AP) to reduce misclassification error in exposure assessment. METHODS Spatio-temporal kriging of daily PM2.5 and ozone (O3) was used to produce daily exposure estimates at the residence ZIP code. Time-stratified case-crossover analysis was conducted to examine short-term effects of PM2.5 on CVD mortality, adjusting for O3 and apparent mean temperature. We studied both single and distributed lags for days 0-5. All CVD mortality and subcategories of ischemic heart disease (IHD), acute myocardial infarction, cerebrovascular disease, peripheral vascular disease (PVD), heart failure and cardiac arrhythmia were examined. RESULTS A total of 62,135 deaths were identified. We found significant associations of PM2.5 with IHD and PVD mortality at lag day 5: (2.1% (95% CI, 0.2-4.1%) and (7.6%, 95% CI, 0.05-15.7%) per 10µg/m3 increase of PM2.5 in single lag models and for IHD in distributed lag models. There were no statistically significant associations with PM2.5 for any of the other outcomes. CONCLUSIONS The application of finer scale geographically resolved AP exposures made it possible to study acute effects of PM2.5 on CVD mortality in a large metropolitan area. Our study results demonstrated the continued presence of a dose response relationship of increased risk of CVD mortality within this lower range of PM2.5 exposure.

Characterization of the concentration-response curve for ambient ozone and acute respiratory morbidity in 5 US cities

Although short-term exposure to ambient ozone (O3) can cause poor respiratory health outcomes, the shape of the concentration-response (C-R) between O3 and respiratory morbidity has not been widely investigated. We estimated the effect of daily O3 on emergency department (ED) visits for selected respiratory outcomes in 5 US cities under various model assumptions and assessed model fit. Population-weighted average 8-h maximum O3 concentrations were estimated in each city. Individual-level data on ED visits were obtained from hospitals or hospital associations. Poisson log-linear models were used to estimate city-specific associations between the daily number of respiratory ED visits and 3-day moving average O3 levels controlling for long-term trends and meteorology. Linear, linear-threshold, quadratic, cubic, categorical, and cubic spline O3 C-R models were considered. Using linear C-R models, O3 was significantly and positively associated with respiratory ED visits in each city with rate ratios of 1.02–1.07 per 25 ppb. Models suggested that O3-ED C-R shapes were linear until O3 concentrations of roughly 60 ppb at which point risk continued to increase linearly in some cities for certain outcomes while risk flattened in others. Assessing C-R shape is necessary to identify the most appropriate form of the exposure for each given study setting.

Mobility and Vitality Lifestyle Program (MOVE UP): A Community Health Worker Intervention for Older Adults With Obesity to Improve Weight, Health, and Physical Function

Abstract Background and Objectives Obesity rates in adults ≥65 years have increased more than other age groups in the last decade, elevating risk for chronic disease and poor physical function, particularly in underserved racial and ethnic minorities. Effective, sustainable lifestyle interventions are needed to help community-based older adults prevent or delay mobility disability. Design, baseline recruitment, and implementation features of the Mobility and Vitality Lifestyle Program (MOVE UP) study are reported. Research Design and Methods MOVE UP aimed to recruit 26 intervention sites in underserved areas around Allegheny County, Pennsylvania and train a similar number of community health workers to deliver a manualized intervention to groups of approximately 12 participants in each location. We adapted a 13-month healthy aging/weight management intervention aligned with several evidence-based lifestyle modification programs. A nonrandomized, pre–post design was used to measure intervention impact on physical function performance, the primary study endpoint. Secondary outcomes included weight, self-reported physical activity and dietary changes, exercise self-efficacy, health status, health-related quality of life, and accelerometry in a subsample. Results Of 58 community-based organizations approached, nearly half engaged with MOVE UP. Facilities included neighborhood community centers (25%), YMCAs (25%), senior service centers (20%), libraries (18%), senior living residences (6%), and churches (6%). Of 24 site-based cohorts with baseline data completed through November 2017, 21 community health workers were recruited and trained to implement the standardized intervention, and 287 participants were enrolled (mean age 68 years, 89% female, 33% African American, other, or more than one race). Discussion and Implications The MOVE UP translational recruitment, training, and intervention approach is feasible and could be generalizable to diverse aging individuals with obesity and a variety of baseline medical conditions. Additional data regarding strategies for program sustainability considering program cost, organizational capacity, and other adaptations will inform public health dissemination efforts.