Epidemiology Commons^™

National Estimates Of Emergency Department Visits For Pediatric Severe Sepsis In The United States, Sara Singhal, Mathias W. Allen, John-Ryan Mcannally, Kenneth S. Smith, John P. Donnelly, Henry E. Wang

Emergency Medicine Faculty Publications

Objective. We sought to determine the characteristics of children presenting to United States (US) Emergency Departments (ED) with severe sepsis.

Study design. Cross-sectional analysis using data from the National Hospital Ambulatory Medical Care Survey (NHAMCS). Using triage vital signs and ED diagnoses (defined by the International Classification of Diseases, Ninth Revision codes), we identified children(triage fever or ICD-9 infection) and organ dysfunction (triage hypotension or ICD-9 organ dysfunction).

Results. Of 28.2 million pediatric patients presenting to US EDs each year, severe sepsis was present in 95,055 (0.34%; 95% CI: 0.29-0.39%). Fever and respiratory infection were the most common indicators of …

The Psychological Impacts Of False Positive Ovarian Cancer Screening: Assessment Via Mixed And Trajectory Modeling, Amanda T. Wiggins

Theses and Dissertations--Epidemiology and Biostatistics

Ovarian cancer (OC) is the fifth most common cancer among women and has the highest mortality of any cancer of the female reproductive system. The majority (61%) of OC cases are diagnosed at a distant stage. Because diagnoses occur most commonly at a late-stage and prognosis for advanced disease is poor, research focusing on the development of effective OC screening methods to facilitate early detection in high-risk, asymptomatic women is fundamental in reducing OC-specific mortality. Presently, there is no screening modality proven efficacious in reducing OC-mortality. However, transvaginal ultrasonography (TVS) has shown value in early detection of OC. TVS presents …

Task-Based Noise Exposures For Farmers Involved In Grain Production, Michael J. Humann, Wayne T. Sanderson, Kelley J. Donham, Kevin M. Kelly

Epidemiology and Environmental Health Faculty Publications

Few studies have been done examining noise exposures associated with agricultural tasks. This study was conducted to address that research gap by calculating the noise exposures for tasks and equipment associated with grain production and assessing the variability in those exposures. An additional aim of this study was to identify tasks and equipment that could be targeted for intervention strategies as a means toward reducing the total noise exposures of farmers and farm workers. Through the use of personal noise dosimetry and direct observation, over 30,000 one-minute noise exposure measurements and corresponding task and equipment data were collected on 18 …

Using Geospatial Technologies To Characterize Relationships Between Travel Behavior, Food Availability, And Health, Warren J. Christian

Theses and Dissertations--Geography

Epidemic obesity in the U.S. has prompted exploration of causal factors related to the built environment. Recent research has noted statistical associations between the spatial accessibility of retail food sources, such as supermarkets, convenience stores, and restaurants, and individual characteristics such as weight, socioeconomic status, and race/ethnicity. These studies typically use residential proximity or neighborhood density to food sources as the measure of accessibility. Assessing food environments in this manner, however, is very limiting. Since most people travel outside of their neighborhood on a daily basis, the retail food sources available to individuals residing in the same area could vary …

Data Mining And Pattern Discovery Using Exploratory And Visualization Methods For Large Multidimensional Datasets, Hsin-Fang Li

Theses and Dissertations--Epidemiology and Biostatistics

Oral health problems have been a major public health concern profoundly affecting people’s general health and quality of life. Given that oral health data is composed of several measurable dimensions including clinical measurements, socio-behavioral factors, genetic predispositions, self-reported assessments, and quality of life measures, strategies for analyzing multidimensional data are neither computationally straightforward nor efficient. Researchers face major challenges to identify tools that circumvent the processes of manually probing the data.

The purpose of this dissertation is to provide applications of the proposed methodology on oral health-related data that go beyond identifying risk factors from a single dimension, and to …

Cattle-Related Injuries And Farm Management Practices On Kentucky Beef Cattle Farms, Steven R. Browning, Susan C. Westneat, Wayne T. Sanderson, Deborah B. Reed

Epidemiology and Environmental Health Faculty Publications

While working on farms with livestock increases the risk of injury among farm workers in comparison to other commodity farms, few studies have examined the role offarm management practices in association with the risk of cattle-related injury. We examined the farm management practices of Kentucky beef cattle farms in association with self-reported rates of cattle-related injuries among workers. We conducted a mail survey of a random sample of 2,500 members of the Kentucky Cattlemen's Association. Results from 1,149 farm operators who were currently raising beef cattle and provided complete survey response are reported. During the busy season, the principal operator …

Does Place Of Residence Affect Risk Of Suicide? A Spatial Epidemiologic Investigation In Kentucky From 1999 To 2008, Daniel M. Saman, Sabrina Walsh, Anna Borówko, Agricola Odoi

Epidemiology and Environmental Health Faculty Publications

BACKGROUND: Approximately 32,000 people take their own lives every year in the United States. In Kentucky, suicide mortality rates have been steadily increasing since 1999. Few studies in the United States have assessed spatial clustering of suicides. The purpose of this study was to identify high-risk clusters of suicide at the county level in Kentucky and assess the characteristics of those suicide cases within the clusters.

METHODS: A spatial epidemiological study was undertaken using suicide data for the period January 1, 1999 to December 31, 2008, obtained from the Kentucky Office of Vital Statistics. Descriptive analyses using Pearson's chi-square test …

A Spatial Cluster Analysis Of Tractor Overturns In Kentucky From 1960 To 2002, Daniel M. Saman, Henry P. Cole, Agricola Odoi, Melvin L. Myers, Daniel I. Carey, Susan C. Westneat

Epidemiology and Environmental Health Faculty Publications

BACKGROUND: Agricultural tractor overturns without rollover protective structures are the leading cause of farm fatalities in the United States. To our knowledge, no studies have incorporated the spatial scan statistic in identifying high-risk areas for tractor overturns. The aim of this study was to determine whether tractor overturns cluster in certain parts of Kentucky and identify factors associated with tractor overturns.

METHODS: A spatial statistical analysis using Kulldorff's spatial scan statistic was performed to identify county clusters at greatest risk for tractor overturns. A regression analysis was then performed to identify factors associated with tractor overturns.

RESULTS: The spatial analysis …

Atrazine Exposure In Public Drinking Water And Preterm Birth, Jessica L. Rinsky, Claudia Hopenhayn, Vijay Golla, Steven R. Browning, Heather M. Bush

Epidemiology and Environmental Health Faculty Publications

Objectives

Approximately 13% of all births occur prior to 37 weeks gestation in the U.S. Some established risk factors exist for preterm birth, but the etiology remains largely unknown. Recent studies have suggested an association with environmental exposures. We examined the relationship between preterm birth and exposure to a commonly used herbicide, atrazine, in drinking water.

Methods

We reviewed Kentucky birth certificate data for 2004–2006 to collect duration of pregnancy and other individual-level covariates. We assessed existing data sources for atrazine levels in public drinking water for the years 2000–2008, classifying maternal county of residence into three atrazine exposure groups. …

Evaluating Retention In Medical Care And Its Impact On The Health Outcomes Of Individuals Living With Human Inmmunodeficiency Virus, Timothy N. Crawford

Theses and Dissertations--Epidemiology and Biostatistics

In the last few years, engagement in medical care among individuals living with HIV has become a major priority among HIV medical providers and public health researchers. Engagement in medical care is an important concept as it involves the process of linking newly diagnosed individuals into medical care and retaining those individuals in care throughout the course of their infection. Although there have been major advances in the management of HIV, like the advent of Highly Active Antiretroviral Therapy, morbidity and mortality due to HIV cannot be fully reduced if the individual does not optimally retain in care. Retention in …

Exploration And Comparison Of Methods For Combining Population- And Family-Based Genetic Association Using The Genetic Analysis Workshop 17 Mini-Exome, David W. Fardo, Anthony R. Druen, Jinze Liu, Lucia Mirea, Claire Infante-Rivard, Patrick Breheny

Biostatistics Faculty Publications

We examine the performance of various methods for combining family- and population-based genetic association data. Several approaches have been proposed for situations in which information is collected from both a subset of unrelated subjects and a subset of family members. Analyzing these samples separately is known to be inefficient, and it is important to determine the scenarios for which differing methods perform well. Others have investigated this question; however, no extensive simulations have been conducted, nor have these methods been applied to mini-exome-style data such as that provided by Genetic Analysis Workshop 17. We quantify the empirical power and false-positive …

Farmwork-Related Injury Among Farmers 50 Years Of Age And Older In Kentucky And South Carolina: A Cohort Study, 2002-2005, Jennifer L. Marcum, Steven R. Browning, Deborah B. Reed, Richard Charnigo

Epidemiology and Environmental Health Faculty Publications

Farmers in the U.S. are becoming more diverse; the average age of the farmer is increasing, as is the number of women and minority farm operators. There is limited research on injury risk factors in these special populations of farmers. It is especially important to study the risk factors for injury in these growing and at-risk groups. A longitudinal survey was conducted of farmers (n = 1,394) age 50 and older who resided in Kentucky and South Carolina. The questionnaire was administered by telephone and mail surveys four times between 2002 and 2005 to the fixed cohort of farmers, obtained …

Does Comorbidity Explain The Ethnic Inequalities In Cervical Cancer Survival In New Zealand? A Retrospective Cohort Study, Naomi Brewer, Barry Borman, Diana Sarfati, Mona Jeffreys, Steven T. Fleming, Soo Cheng, Neil Pearce

Epidemiology and Environmental Health Faculty Publications

BACKGROUND: There are large ethnic differences in cervical cancer survival in New Zealand that are only partly explained by stage at diagnosis. We investigated the association of comorbidity with cervical cancer survival, and whether comorbidity accounted for the previously observed ethnic differences in survival.

METHODS: The study involved 1,594 cervical cancer cases registered during 1994-2005. Comorbidity was measured using hospital events data and was classified using the Elixhauser instrument; effects on survival of individual comorbid conditions from the Elixhauser instrument were also assessed. Cox regression was used to estimate adjusted cervical cancer mortality hazard ratios (HRs).

RESULTS: Comorbidity during the …

Kriged And Modeled Ambient Air Levels Of Benzene In An Urban Environment: An Exposure Assessment Study, Kristina W. Whitworth, Elaine Symanski, Dejian Lai, Ann L. Coker

CRVAW Faculty Journal Articles

Background. There is increasing concern regarding the potential adverse health effects of air pollution, particularly hazardous air pollutants (HAPs). However, quantifying exposure to these pollutants is problematic. Objective. Our goal was to explore the utility of kriging, a spatial interpolation method, for exposure assessment in epidemiologic studies of HAPs. We used benzene as an example and compared census tract-level kriged predictions to estimates obtained from the 1999 U.S. EPA National Air Toxics Assessment (NATA), Assessment System for Population Exposure Nationwide (ASPEN) model. Methods. Kriged predictions were generated for 649 census tracts in Harris County, Texas using estimates of annual benzene …

Preventing Cardiovascular Disease In Kentucky: Epidemiology, Trends, And Strategies For The Future, Sarah Sartini Rugg, Alison L. Bailey, Steven R. Browning

Internal Medicine Faculty Publications

Cardiovascular disease (CVD) is the leading cause of death in the United States despite dramatic improvements in the treatment of heart disease in recent years. Kentucky leads the nation in the prevalence of several individual risk factors for cardiovascular disease, the prevalence of multiple risk factors, and in cardiovascular mortality. While trends in the prevalence of some of these cardiac risk factors have shown improvement, others have remained unchanged or have worsened. The increased prevalence of obesity and diabetes, especially among young persons, is one of the most worrisome trends. The prevalence of smoking in Kentucky remains high, and has …

Suicides Among Farmers In Three Southeastern States, 1990-1998, Steven R. Browning, Susan C. Westneat, Robert H. Mcknight

Epidemiology and Environmental Health Faculty Publications

Several studies have documented higher rates of suicide among farmers in comparison to other occupational groups, both in the U.S. and internationally. The purpose of this study is to describe the epidemiology of farmer suicides in three southeastern states (Kentucky, North Carolina, and South Carolina) during the nine-year period 1990-1998. Electronic death certificate data were obtained from the National Center for Health Statistics. Over the nine-year period, there were 590 deaths related to suicide (E-codes: 950-959) among farmers (occupation codes: 473, 474, 475, 477, and 479) in the states of Kentucky, North Carolina, and South Carolina. The results of this …

Tractor Driving Among Kentucky Farm Youth: Results From The Farm Family Health And Hazard Surveillance Project, Steven R. Browning, Susan C. Westneat, Raeanne Szeluga

Epidemiology and Environmental Health Faculty Publications

This article documents the extent of children's involvement in tractor operations among a representative sample of Kentucky children living and working on family farms. Specifically, we describe children's exposures to tractor-related work activities, profile their use of the tractor (number of days worked), and assess compliance with generally recommended safety measures, such as using tractors equipped with ROPS (rollover protective structures), avoiding riding as passengers on tractors, and operating tractors on public roadways. Data for this study were collected in 1994 and 1995 as part of the NIOSH-sponsored Farm Family Health and Hazard Surveillance Project (FFHHSP). Despite recognition in the …

Chronic Arsenic Exposure And Risk Of Infant Mortality In Two Areas Of Chile, Claudia Hopenhayn-Rich, Steven R. Browning, Irva Hertz-Picciotto, Catterina Ferreccio, Cecilia Peralta, Herman Gibb

Preventive Medicine and Environmental Health Faculty Publications

Chronic arsenic exposure has been associated with a range of neurologic, vascular, dermatologic, and carcinogenic effects. However, limited research has been directed at the association of arsenic exposure and human reproductive health outcomes. The principal aim of this study was to investigate the trends in infant mortality between two geographic locations in Chile: Antofagasta, which has a well-documented history of arsenic exposure from naturally contaminated water, and Valparaíso, a comparable low-exposure city. The arsenic concentration in Antofagasta's public drinking water supply rose substantially in 1958 with the introduction of a new water source, and remained elevated until 1970. We used …