Amber H. Sinclair

Associations and Lags between Air Pollution and Acute Respiratory Visits in an Ambulatory Care Setting: 25-Month Results from the Aerosol Research and Inhalation Epidemiological Study

Abstract Particulate matter (PM) has been associated with adverse respiratory outcomes in numerous studies that utilized data from emergency room visits, hospital admissions, and mortality records. This study is unique in its investigation of associations of air pollution measures, including components of PM, with health outcomes in an ambulatory-care setting. Visit data were collected from Kaiser Permanente, a not-for-profit health maintenance organization in the metropolitan Atlanta, GA, area. Kaiser Permanente collaborated on the Aerosol Research Inhalation Epidemiological Study (ARIES), which provided detailed information on the characteristics of air pollutants. The Kaiser Permanente study was a time-series investigation of the possible associations between daily levels of suspended PM, inorganic gases, and polar volatile organic compounds and ambulatory care acute visit rates during the 25-month period from August 1, 1998, to August 31, 2000. For this interim analysis, the a priori 0–2 days lagged moving average, as well as the 3–5 days and 6–8 days lagged moving averages, of air quality measures were investigated. Single-pollutant Poisson general linear modeling was used to model daily visit counts for asthma and upper and lower respiratory infections (URI and LRI) by selected air quality metrics, controlling for temporal trends and meteorological variables. Most of the statistically significant positive associations were for the 3–5 days lagged air quality metrics with child asthma and LRI.

Methods for Characterizing Fine Particulate Matter Using Ground Observations and Remotely Sensed Data: Potential Use for Environmental Public Health Surveillance

Abstract This study describes and demonstrates different techniques for surface fitting daily environmental hazards data of particulate matter with aerodynamic diameter less than or equal to 2.5 μm (PM2.5) for the purpose of inte grating respiratory health and environmental data for the Centers for Disease Control and Prevention (CDC) pilot study of Health and Environment Linked for Information Exchange (HELIX)–Atlanta. It presents a methodology for estimating daily spatial surfaces of ground-level PM2.5 concentrations using the B-Spline and inverse distance weighting (IDW) surface-fitting techniques, leveraging National Aeronautics and Space Administration (NASA) Moderate Resolution Imaging Spectrometer (MODIS) data to complement U.S. Environmental Protection Agency (EPA) ground observation data. The study used measurements of ambient PM2.5 from the EPA database for the year 2003 as well as PM2.5 estimates derived from NASA’s satellite data. Hazard data have been processed to derive the surrogate PM2.5 exposure estimates. This paper shows that merging MODIS remote sensing data with surface observations of PM2.5 not only provides a more complete daily representation of PM2.5 than either dataset alone would allow, but it also reduces the errors in the PM2.5- estimated surfaces. The results of this study also show that although the IDW technique can introduce some numerical artifacts that could be due to its interpolating nature, which assumes that the maxima and minima can occur only at the observation points, the daily IDW PM2.5 surfaces had smaller errors in general, with respect to observations, than those of the B-Spline surfaces. Finally, the methods discussed in this paper establish a foundation for environmental public health linkage and association studies for which determining the concentrations of an environmental hazard such as PM2.5 with high accuracy is critical.

Gender differences in asthma experience and disease care in a managed care organization.

The purpose of this study was to describe gender differences in asthma in a managed care organization. We collected data from a patient survey, electronic administrative data, and hard-copy chart reviews. Women reported significantly lower general health status, more symptoms and greater severity of asthma, more activity limitations, more use of asthma-relieving medications, and more acute visits for asthma than men. Conversely, women tended to report better asthma care measures. These gender disparities warrant further study to support appropriate adjustment of clinical care and health-care-related services for women.

A Two-Time-Period Comparison of the Effects of Ambient Air Pollution on Outpatient Visits for Acute Respiratory Illnesses

Abstract Concentrations of numerous ambient air pollutants have declined in recent years across the United States. Although it can be expected that reductions in air pollutants are associated with reductions in health effects, it is unclear whether this is actually the case. The purpose of this analysis was to compare the levels of and relationships between air pollutants and acute respiratory outpatient visits for two consecutive time periods totaling 53 mo. Air pollution data were collected at a centrally located monitor in Atlanta, GA, and include 24-hr averages of particulate matter (PM) less than 2.5 μm in aerodynamic diameter (PM2.5) and its components; coarse PM (PM10-2.5); PM less than 10 μm in aerodynamic diameter (PM10); oxygenated volatile organic compounds (OVOCs); 8-hr maximum ozone (O3); and 1-hr maximum nitrogen dioxide (NO2), carbon monoxide (CO), and sulfur dioxide (SO2). In addition, several metals and fractions of elemental carbon (EC) and organic carbon (OC) were investigated. Daily outpatient visit data were obtained from the electronic data warehouse of the Atlanta-based region of a nonprofit managed care organization. Poisson general linear modeling determined associations between daily levels of acute visits for four diagnosis groups (adult and child asthma, upper and lower respiratory infection) and air pollution measurements. Overall declining trends were observed in air pollutants and acute visits over the study period. Childhood asthma had the greatest number of significant associations with air pollutants, namely zinc and EC. The significant lag time between pollutant measurement and visit occurrence changed from 3-5 days in the first time period to 6-8 days in the later time period, but there was general consistency in several childhood asthma and pollutant associations over both time periods. The greatest evidence for a reduction in pollution being associated with an improvement in health response was for lower respiratory disease visits, but even in this case changes in other factors that influence health responses make it difficult to demonstrate that changes in pollutant levels influence health outcomes.

Childhood Asthma Acute Primary Care Visits, Traffic, and Traffic-Related Pollutants

UNLABELLED Previous studies have found associations between traffic-related air pollution and asthma exacerbation in children, where exacerbations were measured according to emergency department visits and hospital admissions. Fewer studies have been undertaken that look at asthma exacerbations in a less severe primary care setting. Therefore, the authors sought to examine the associations between childhood asthma exacerbations, measured as acute visits to a primary care setting, and vehicular-traffic measures in a population of children aged 18 and under in the metropolitan Atlanta area. Statistical tests for differences of mean monthly visits for members with traffic measures above the median compared with below the median and for the upper quartile compared with the lower quartile were conducted. We also compared the odds of having one or more visits in a month for those who lived closer to a major roadway were compared with those who lived farther (greater than 300 m) from a major roadway. Poisson general linear modeling was used to determine associations between daily levels of acute visits for childhood asthma and traffic-related pollutants (zinc, EC [elemental carbon], and PM10 and PM2.5 [particulate matter with an aerodynamic diameter of < or = 10 and < or = 2.5 microm, respectively]) for different levels of traffic and distance measures. This analysis found that both larger traffic volumes and smaller distances to the nearest major roadway were positively and significantly associated with larger numbers of childhood asthma visits, when compared with less traffic and larger distances. Our findings point to motor vehicle traffic as an important contributor to childhood asthma exacerbations. IMPLICATIONS Previous studies have found associations between traffic-related air pollution and asthma exacerbation in children. However, these studies were mainly conducted in emergency department or hospital admission settings; little is known regarding less acute health effects. This analysis of the association between vehicular traffic measures and childhood asthma in a primary care setting suggests that motor vehicle traffic is a contributor to less acute asthma episodes in children. The present analysis of traffic-related air pollutants and childhood asthma were less conclusive, likely due to methods limitations outlined in the paper. The implication is that further evidence of adverse respiratory health effects in children due to motor vehicle traffic can be found in a primary care setting and similar studies should be considered.

A Comparison of the Effects of Ambient Air Pollution on Outpatient Visits for Acute Respiratory Illnesses Over Two Time Periods

Abstracts published in EPIDEMIOLOGY have been reviewed by the organizations of EPIDEMIOLOGY. Affliate Societies at whose meetings the abstracts have been accepted for presentation. These abstracts have not undergone review by the Editorial Board of EPIDEMIOLOGY.s published in EPIDEMIOLOGY have been reviewed by the organizations of EPIDEMIOLOGY. Affliate Societies at whose meetings the abstracts have been accepted for presentation. These abstracts have not undergone review by the Editorial Board of EPIDEMIOLOGY. ISEE 21st Annual Conference, Dublin, Ireland, August 25–29, 2009

Feasibility of conducting a large, randomized controlled trial for STD counseling in a managed care setting.

Background: Screening for, and prevention of, sexually transmitted diseases requires access to the adolescent, which is often difficult. The primary care visit can offer an opportunity to provide prevention counseling to adolescents. The objective of this study was to determine the feasibility of conducting a large randomized, controlled trial of sexually transmitted diseases counseling intervention in a managed care setting. Methods: A randomized, controlled trial of a counseling intervention was compared with usual care in a managed care organization in a southeastern United States urban area. Members aged 14- to 25-years old who tested positive for gonorrhea or chlamydia during the study period were randomized to receive either a two-part brief counseling intervention or usual care. Results: Among 93 members who tested chlamydia- or gonorrhea-positive and who were eligible to enroll, contact could not be made for 47 members, and only 12 of the remaining members enrolled in the study. Conclusions: It would be problematic to implement a full-scale trial of this intervention in this practice environment without significant changes in clinical and intervention processes. The need for counseling services for sexually transmitted diseases remains great.