Travel-Time Disparities in Access to Proton Beam Therapy for Cancer Treatment

Importance

Proton beam therapy is an emerging radiotherapy treatment for patients with cancer that may produce similar outcomes as traditional photon-based therapy for many cancers while delivering lower amounts of toxic radiation to surrounding tissue. Geographic proximity to a proton facility is a critical component of ensuring equitable access both for indicated diagnoses and ongoing clinical trials.

Objective

To characterize the distribution of proton facilities in the US, quantify drive-time access for the population, and investigate the likelihood of long commutes for certain population subgroups.

Design, Setting, and Participants

This population-based cross-sectional study analyzed travel times to proton facilities in the US. Census tract variables in the contiguous US were measured between January 1, 2017, and December 31, 2021. Statistical analysis was performed from September to November 2023.

Exposures

Drive time in minutes to nearest proton facility. Population totals and prevalence of specific factors measured from the American Community Survey: age; race and ethnicity; insurance, disability, and income status; vehicle availability; broadband access; and urbanicity.

Main Outcomes and Measures

Poor access to proton facilities was defined as having a drive-time commute of at least 4 hours to the nearest location. Median drive time and percentage of population with poor access were calculated for the entire population and by population subgroups. Univariable and multivariable odds of poor access were also calculated for certain population subgroups.

Results

Geographic access was considered for 327 536 032 residents of the contiguous US (60 594 624 [18.5%] Hispanic, 17 974 186 [5.5%] non-Hispanic Asian, 40 146 994 [12.3%] non-Hispanic Black, and 195 265 639 [59.6%] non-Hispanic White; 282 031 819 [86.1%] resided in urban counties). The median (IQR) drive time to the nearest proton facility was 96.1 (39.6-195.3) minutes; 119.8 million US residents (36.6%) lived within a 1-hour drive of the nearest proton facility, and 53.6 million (16.4%) required a commute of at least 4 hours. Persons identifying as non-Hispanic White had the longest median (IQR) commute time at 109.8 (48.0-197.6) minutes. Multivariable analysis identified rurality (odds ratio [OR], 2.45 [95% CI, 2.27-2.64]), age 65 years or older (OR, 1.09 [95% CI, 1.06-1.11]), and living below the federal poverty line (OR, 1.22 [1.20-1.25]) as factors associated with commute times of at least 4 hours.

Conclusions and Relevance

This cross-sectional study of drive-time access to proton beam therapy found that disparities in access existed among certain populations in the US. These results suggest that such disparities present a barrier to an emerging technology in cancer treatment and inhibit equitable access to ongoing clinical trials.

Geographic variation of HPV-associated cancer incidence in Kentucky using spatial scan statistics

PURPOSE

Populations with high cancer risk that are targeted for screening, education, and vaccination have been shown to increase rates of screening, which ultimately may improve timing of diagnosis and overall outcome for certain cancers. Spatial scan analysis provides a visual representation of areas with higher rates of disease. Limited research has used this methodology to assess HPV-associated cancers. Using, spatial scan statistics, our goal was to identify regions within Kentucky having significantly higher rates of HPV-associated tumors. These regions can be targeted for public health efforts in the form of education, vaccination, screening, and physician recruitment.

METHODS

The Kentucky Cancer Registry data from 1995 to 2016 and spatial scan statistics were used to identify county-level clusters with high-incidence of HPV-associated cancers after adjustment for age and sex. Anatomic sites included in this analysis were oropharynx, cervix, anus, penis, and vulva.

RESULTS

There was one high-rate cluster of oropharyngeal cancer, which was observed in the Louisville metropolitan region (Relative Risk [RR] = 1.24, p < 0.001). One high-rate cluster of anal and penile cancer incidence in men was identified that partially overlapped with the oropharyngeal cluster. There were five clusters of higher cervical, vulvar, and anal cancer incidence in females, one of which overlapped with the oropharyngeal cluster.

CONCLUSION

Overlapping clusters of HPV-associated cancers were identified at the county-level and included both urban and rural counties of Kentucky. Findings can assist in the design of public health interventions to increase screenings, promote vaccination, and recruit physicians in these regions to improve prevention, diagnosis, and early treatment of HPV-associated cancers.

Trends in Oral Tongue Cancer Incidence in the US

Importance

Oral tongue cancer (OTC) incidence has increased rapidly among young (<50 years) non-Hispanic White individuals in the US during the past 2 decades; however, it is unknown if age-associated trajectories have persisted.

Objective

To examine US trends in OTC incidence and project future case burden.

Design, Setting, and Participants

This cross-sectional analysis of OTC incidence trends used the US Cancer Statistics Public Use Database, which covers approximately 98% of the US population, and included individuals with an OTC diagnosis reported to US cancer registries between January 1, 2001, and December 31, 2019.

Exposures

Sex, race and ethnicity, and age.

Main Outcomes and Measures

Estimated average annual percentage change in OTC incidence from 2001 to 2019. Given the substantial incidence rate increases among non-Hispanic White individuals compared with those of racial and ethnic minority groups, subsequent analyses were restricted to non-Hispanic White individuals. Forecasted OTC incidence trends and case burden among non-Hispanic White individuals to 2034.

Results

There were 58 661 new cases of OTC identified between 2001 and 2019. Male individuals (57.6%), non-Hispanic White individuals (83.7%), those aged 60 years or older (58.0%), and individuals with localized stage disease at diagnosis (62.7%) comprised most cases. OTC incidence increased across all age, sex, and racial and ethnic groups, with marked increases observed among non-Hispanic White individuals (2.9% per year; 95% CI, 2.2%-3.7%). Increases among female individuals aged 50 to 59 years were most notable and significantly outpaced increases among younger non-Hispanic White female individuals (4.8% per year [95% CI, 4.1%-5.4%] vs 3.3% per year [95% CI, 2.7%-3.8%]). While all non-Hispanic White birth cohorts from 1925 to 1980 saw sustained increases, rates stabilized among female individuals born after 1980. Should trends continue, the burden of new OTC cases among non-Hispanic White individuals in the US is projected to shift more toward older individuals (from 33.1% to 49.3% among individuals aged 70 years or older) and female individuals (86% case increase vs 62% among male individuals).

Conclusions and Relevance

The results of this cross-sectional study suggest that the period of rapidly increasing OTC incidence among younger non-Hispanic White female individuals in the US is tempering and giving way to greater increases among older female individuals, suggesting a birth cohort effect may have been associated with previously observed trends. Recent increases among non-Hispanic White individuals 50 years or older of both sexes have matched or outpaced younger age groups. Continuing increases among older individuals, particularly female individuals, may be associated with a shift in the OTC patient profile over time.

Diabetes screening among women with Polycystic Ovary Syndrome: A descriptive study of commercial claims, 2011-2019

Background

Polycystic ovary syndrome (PCOS) is a hormonal disorder that affects 6-12% of United States women of reproductive age. Women with PCOS are at an increased risk of developing type 2 diabetes and fall into high-risk groups according to the American College of Obstetricians and Gynecologists (ACOG) screening guidelines. Guidelines further indicate that an oral glucose tolerance test (OGTT) should be used for diabetes screening in women with PCOS instead of an A1C or fasting plasma glucose test. The purpose of this study is two-fold: 1) to estimate rates of diabetes screening among a nationwide sample of commercially insured women with PCOS and 2) to report the percentage of women screened using each test (OGTT, A1C, fasting plasma glucose) among those who were screened.

Methods

We used the MarketScan Commercial Claims database (2011-2019) to identify a sample of women aged 18-64 years with PCOS who were free from diabetes at baseline and had ≥ 5 years of continuous enrollment. PCOS was ascertained using International Classification of Disease diagnosis codes (ICD-9: 256.4; ICD-10: E28.2). Diabetes screening was ascertained using Current Procedural Terminology (CPT) codes (A1C: 83036, 83037; Fasting blood sugar: 82947; OGTT: 82950). Diabetes screening rates were calculated for the overall study sample as well as across subgroups defined by age, overweight/obesity, hypertension, hypercholesterolemia, and vascular disease.

Results

In our sample of 191,110 commercially insured women with PCOS, 73.40% were screened at least once for diabetes during a five-year period. Among the women screened, 19.24% were screened using the Androgen Excess Society (AES)-recommended OGTT, 61.58% were screened using A1C, and 23.37% were screened using fasting blood sugar.

Conclusions

Almost 75% of women with PCOS comply with the ACOG screening guidelines for diabetes. However, while the OGTT is recommended as the preferred screening tool for women with PCOS, it was less commonly used than A1C and fasting blood sugar tests.

Undiagnosed Cancer Cases in the US During the First 10 Months of the COVID-19 Pandemic

Importance

The COVID-19 pandemic disrupted the normal course of cancer screening and detection in the US. A nationwide analysis of the extent of this disruption using cancer registry data has not been conducted.

Objective

To assess the observed and expected cancer rate trends for March through December 2020 using data from all 50 US states and the District of Columbia.

Design, Settings, and Participants

This was a population-based cross-sectional analysis of cancer incidence trends using data on cases of invasive cancer diagnosis reported to the US Cancer Statistics from January 1, 2018, through December 31, 2020. Data analyses were performed from July 6 to 28, 2023.

Exposure(s)

Age, sex, race, urbanicity, and state-level response to the COVID-19 pandemic at the time of cancer diagnosis.

Main Outcomes and Measures

Used time-series forecasting methods to calculate expected cancer incidence rates for March 1 through December 31, 2020, from prepandemic trends (January 2018-February 2020). Measured relative difference between observed and expected cancer incidence rates and numbers of potentially missed cancer cases.

Results

This study included 1 297 874 cancer cases reported in the US from March 1 through December 31, 2020, with an age-adjusted incidence rate of 326.5 cases per 100 000 population. Of the observed cases, 657 743 (50.7%) occurred in male patients, 757 106 (58.3%) in persons 65 years or older, and 1 066 566 (82.2%) in White individuals. Observed rates of all-sites cancer incidence in the US were 28.6% (95% prediction interval [PI], 25.4%-31.7%) lower than expected during the height of the COVID-19 pandemic response (March-May 2020); 6.3% (95% PI, 3.8%-8.8%) lower in June to December 2020; and overall, 13.0% (95% PI, 11.2%-14.9%) lower during the first 10 months of the pandemic. These differences indicate that there were potentially 134 395 (95% PI, 112 544-156 680) undiagnosed cancers during that time frame. Prostate cancer accounted for the largest number of potentially missed cases (22 950), followed by female breast (16 870) and lung (16 333) cancers. Screenable cancers saw a total rate reduction of 13.9% (95% PI, 12.2%-15.6%) compared with the expected rate. The rate of female breast cancer showed evidence of recovery to previous trends after the first 3 months of the pandemic, but levels remained low for colorectal, cervical, and lung cancers. From March to May 2020, states with more restrictive COVID-19 responses had significantly greater disruptions, yet by December 2020, these differences were nonsignificant for all sites except lung, kidney, and pancreatic cancer.

Conclusions and Relevance

This cross-sectional analysis of cancer incidence trends found a substantial disruption to cancer diagnoses in the US during the first 10 months of the COVID-19 pandemic. The overall and differential findings can be used to inform where the US health care system should be looking to make up ground in cancer screening and detection.

Geographic and temporal trends in pediatric and young adult brain tumors in Kentucky, 1995-2019

INTRODUCTION

Pediatric and young adult brain tumors (PYBT) account for a large share of cancer-related morbidity and mortality among children in the United States, but their etiology is not well understood. Previous research suggests the Appalachian region of Kentucky has high rates of PYBT. This study explored PYBT incidence over 25 years in Kentucky to identify geographic and temporal trends and generate hypotheses for future research.

METHODS

The Kentucky Cancer Registry contributed data on all PYBT diagnosed among those aged 0-29 during years 1995-2019. Age- and sex-adjusted spatio-temporal scan statistics-one for each type of PYBT, and one for all types-comprised the primary analysis. These results were mapped along with environmental and occupational data.

RESULTS

Findings indicated that north-central Kentucky and the Appalachian region experienced higher rates of some PYBT. High rates of astrocytomas were clustered in a north-south strip of central Kentucky toward the end of the study period, while high rates of other specified types of intracranial and intraspinal neoplasms were significantly clustered in eastern Kentucky. The area where these clusters overlapped, in north-central Kentucky, had significantly higher rates of PYBT generally.

DISCUSSION

This study demonstrates north-central Kentucky and the Appalachian region experienced higher PYBT risk than the rest of the state. These regions are home to some of Kentucky's signature industries, which should be examined in further research. Future population-based and individual-level studies of genetic factors are needed to explore how the occupations of parents, as well as prenatal and childhood exposures to pesticides and air pollutants, impact PYBT incidence.

Recent and Projected Trends in Oral Tongue Cancer in the United States: A Demographic Shift in Case Burden as Early Onset Increases Among Females Subside

Background

Oral tongue cancer (OTC) incidence has increased rapidly among young (< 50 years) non-Hispanic White (NHW) individuals in the United States (U.S.) over the last two decades; however, it is unknown if age-associated trajectories have persisted. Furthermore, incidence trends for all 50 U.S. states and the District of Columbia have never been investigated.

Materials and methods

Using U.S. Cancer Statistics data, we investigated incidence trends from 2001-2019, overall and according to age, sex, race/ethnicity, and state of residence. We used age-period-cohort analysis to explore temporal patterns among birth cohorts and to project future trends and case counts.

Results

OTC incidence increased across all age, sex, and racial/ethnic groups, with marked increases observed among the NHWs (2.9%/year; 95%CI, 2.2%-3.7%). Incidence among NHWs increased in most U.S. states, particularly in the Southeast. Increases were significantly greater among NHW females compared to males (3.6%/year vs 2.6%/year; P = 0.022). Increases among females aged 50-59 years were most notable and significantly outpaced increases among younger females (4.8%/year [95% CI, 4.1%-5.4%] vs. 3.3%/year [95% CI, 2.7%-3.8%]; P < .001). While both NHW male and female birth cohorts from 1925 to 1980 saw sustained increases, rates stabilized among females born after 1980. Should trends continue, the burden of new OTC cases among NHWs in the U.S. is projected to shift to older individuals (33.1% versus 49.3% aged ≥ 70) and females (86% case increase versus 62% among males).

Conclusion

The period of rapidly increasing OTC incidence among younger NHW females in the U.S. is tempering and giving way to greater increases among older females, suggesting that a birth cohort effect may have influenced previously observed trends. Recent increases among NHWs aged ≥ 50 of both sexes have matched or outpaced younger age groups. Continuing increases among older individuals, particularly females, will lead to a shift in the OTC patient profile over time.

Environmental exposures and pulmonary function among adult residents of rural Appalachian Kentucky

BACKGROUND

Estimated residential exposures of adults to roadway density and several metrics of resource extraction, including coal mining and oil and gas drilling, were hypothesized to contribute to the prevalence of respiratory disease in rural Appalachia.

OBJECTIVE

Determine how small-area geographic variation in residential environmental exposures impacts measures of pulmonary function among adults in a community-based study.

METHODS

We examined associations between residential environmental respiratory exposures and pulmonary function among 827 adult participants of the "The Mountain Air Project", a community-based, cross-sectional study in Southeastern Kentucky during 2016-2018. Exposures characterized the density of roadways, oil/gas wells, or current/past surface and underground coal mining at the level of 14-digit hydrologic unit code (HUC), or valley "hollow" where participants resided. Each participant completed an in-person interview to obtain extensive background data on risk factors, health history, and occupational and environmental exposures, as well as a spirometry test administered by experienced study staff at their place of residence. Multivariable linear regression was used to model the adjusted association between each environmental exposure and percent predicted forced expiratory volume in one second (FEV1PP) and forced vital capacity (FVCPP).

RESULTS

Adjusted regression models indicate persons living in HUCs with the highest level of roadway density experienced a reduction in both FEV1PP (-4.3: 95% CI: -7.44 -1.15;) and FVCPP (-3.8: 95% CI: -6.38, -1.21) versus persons in HUCs with the lowest roadway density. No associations were detected between the metrics associated with mining and oil and gas operations and individual pulmonary function.

IMPACT STATEMENT

Our work demonstrates the potential adverse impact of roadway-related exposures on the respiratory health of rural Appalachia residents. We employed a novel method of small-area exposure classification based on the hydrologic unit code (HUC), representing potential exposure levels per hollow occurring  in proximity to the residence, and controlled for individual-level risk factors for reduced respiratory health. We highlight an overlooked yet ubiquitous source of residential exposure from motor vehicles that may contribute to the regionally high prevalence of respiratory disease in rural Appalachia.

PFAS soil concentrations surrounding a hazardous waste incinerator in East Liverpool, Ohio, an environmental justice community

Per- and polyfluoroalkyl substances (PFAS) are a class of synthetic compounds widely used in industrial and consumer products. While PFAS provide product durability, these chemicals are ubiquitous, persistent, bioaccumulative, and toxic. These characteristics make the ultimate disposal of PFAS a challenge. One current disposal method is incineration; however, little research has been conducted on the safety and effectiveness of PFAS incineration. The characteristics of communities with hazardous waste incinerators that have received PFAS shipments indicate that more individuals with lower incomes and individuals with less education than the US average are at higher risk of exposure, which presents important environmental justice and health equity concerns of PFAS incineration. Situated in eastern Ohio, East Liverpool is an Appalachian community that is home to a large hazardous-waste incinerator, operated by Heritage WTI, that began accepting PFAS in 2019. Residents are concerned that the disposal lacks the research necessary to assure safety for the residents. Due to both community interest and data gaps regarding PFAS incineration, our research team conducted a pilot study to examine the distribution and concentration of PFAS in soil samples surrounding the incinerator. All 35 soil samples had measurable amounts of PFAS including perfluorobutanesulfonic acid (PFBS), perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and hexafluoropropylene oxide dimer acid (HFPO-DA)/GenX. PFOS was measured in the majority of soil samples (97%) with a range of 50-8,300 ng/kg. PFOA was measured in 94% of soil samples with a range of 51 ng/kg to 1300 ng/kg. HFPO-DA/GenX was measurable in 12 soil samples with concentrations of ranging from 150 ng/kg to 1500 ng/kg. Further research on PFAS disposal will advance knowledge and action related to regulatory requirements and exposure prevention, ultimately improving individual and community protections and health equity.

County incidence and geospatial trends of early-onset hypertensive disorders of pregnancy in Kentucky, 2008-2017

BACKGROUND

Early-onset hypertensive disorders of pregnancy (eHDP) are associated with more severe maternal and infant outcomes than later-onset disease. However, little has been done to evaluate population-level trends. Therefore, in this paper, we seek to address this understudied area by describing the geospatial and temporal patterns of county-level incidence of eHDP and assessing county-level demographics that may be associated with an increased incidence of eHDP.

METHODS

Employing Kentucky certificates of live and stillbirth from 2008-2017, this ecological study detected county-level clusters of early-onset hypertensive disorders of pregnancy using SaTScan, calculated average annual percent change (AAPC) with a join point analysis, and identified county-level covariates (% of births to women ≥ 35 years of age, % with BMI ≥ 30 kg/m², % currently smoking, % married, and % experienced eHDP) with a fixed-effects negative binomial regression model for longitudinal data with an autoregressive (AR) correlation structure offset with the natural log of the number of births in each county and year.

RESULTS

County-level incidence of eHDP had a non-statistically significant increase of almost 3% (AAPC: 2.84, 95% CI: -4.26, 10.46), while maternal smoking decreased by almost 6% over the study period (AAPC:-5.8%, 95%CI: -7.5, -4.1), Risk factors for eHDP such as pre-pregnancy BMI ≥ 30 and proportion of births to women ≥ 35 years of age increased by 2.3% and 3.4% respectively (BMI AAPC:2.3, 95% CI: 0.94, 3.7; ≥ 35 years AAPC:3.4, 95% CI: 0.66, 6.3). After adjusting for race, county-level proportions of college attainment, and maternal smoking throughout pregnancy, counties with the highest proportion of births to women with BMI ≥ 30 kg/m² reported an eHDP incidence 20% higher than counties with a lower proportion of births to mothers with a BMI ≥ 30 kg/m² and a 20% increase in eHDP incidence (aRR = 1.20, 95% CI: 1.00, 1.44). We also observed that counties with the highest proportion vs. the lowest of mothers ≥ 35 years old (> 6.1%) had a 26% higher incidence of eHDP (RR = 1.26, 95%CI: 1.04, 1.50) compared to counties with the lowest incidence (< 2.5%). We further identified two county-level clusters of elevated eHDP rates. We also observed that counties with the highest vs. lowest proportion of mothers ≥ 34 years old (> 6.1% vs. < 2.5%) had a 26% increase in the incidence of eHDP (RR = 1.26, 95% CI: 1.04, 1.50). We further identified two county-level clusters of elevated incidence of eHDP.

CONCLUSIONS

This study identified two county-level clusters of eHDP, county-level covariates associated with eHDP, and that while increasing, the average rate of increase for eHDP was not statistically significant. This study also identified the reduction in maternal smoking over the study period and the concerning increase in rates of elevated pre-pregnancy BMI among mothers. Further work to explore the population-level trends in this understudied pregnancy complication is needed to identify community factors that may contribute to disease and inform prevention strategies.

Adult asthma associated with roadway density and housing in rural Appalachia: the Mountain Air Project (MAP)

BACKGROUND

Appalachian Kentucky is a rural area with a high prevalence of asthma among adults. The relative contribution of environmental exposures in the etiology of adult asthma in these populations has been understudied.

OBJECTIVE

This manuscript describes the aims, study design, methods, and characteristics of participants for the Mountain Air Project (MAP), and focuses on associations between small area environmental exposures, including roadways and mining operations, and lifetime and current asthma in adults.

METHODS

A cohort of residents, aged 21 and older, in two Kentucky counties, was enrolled in a community-based, cross-sectional study. Stratified cluster sampling was used to select small geographic areas denoted as 14-digit USGS hydrologic units (HUCs). Households were enumerated within selected HUCs. Community health workers collected in-person interviews. The proximity of nearby active and inactive coal mining operations, density of oil and gas operations, and density of roadways were characterized for all HUCs. Poisson regression analyses were used to estimate adjusted prevalence ratios.

RESULTS

From 1,459 eligible households contacted, 1,190 individuals were recruited, and 972 persons completed the interviews. The prevalence of lifetime asthma was 22.8%; current asthma was 16.3%. Adjusting for covariates, roadway density was positively associated with current asthma in the second (aPR = 1.61; 95% CI 1.04-2.48) and third tertiles (aPR = 2.00; 95% CI 1.32-3.03). Increased risk of current asthma was associated with residence in public, multi-unit housing (aPR = 2.01; 95% CI 1.27-3.18) compared to a residence in a single-family home. There were no notable associations between proximity to coal mining and oil and gas operations and asthma prevalence.

CONCLUSIONS

This study suggests that residents in rural areas with higher roadway density and those residing in public housing units may be at increased risk for current asthma after accounting for other known risk factors. Confirming the role of traffic-related particulates in producing high asthma risk among adults in this study contributes to the understanding of the multiple environmental exposures that influence respiratory health in the Appalachia region.

Investigating the Relation between Electronic Cigarette Use and Sleep Duration in Kentucky Using the BRFSS, 2016-2017

OBJECTIVES

Like traditional cigarettes, electronic cigarettes (e-cigarettes) contain nicotine, which is known to negatively influence sleep quality. Few studies, however, have examined the relation between e-cigarettes and sleep quality using population-based survey data because of the relatively recent appearance of these products on the market. This study investigated the relation between e-cigarette and cigarette use and sleep duration in Kentucky, a state with high rates of nicotine dependence and related chronic diseases.

METHODS

Data from two consecutive years of the Behavioral Risk Factor Surveillance System survey-2016 and 2017-were analyzed using χ² statistics and multivariable Poisson regression analyses to control for socioeconomic and demographic variables, the presence of other chronic diseases, and traditional cigarette use.

RESULTS

This study was conducted using responses from 18,907 Kentucky adults aged 18 years and older. Overall, almost 40% reported short (<7 hours) sleep duration. After adjusting for other covariates, including the presence of chronic diseases, those who had currently or formerly used both traditional and e-cigarettes had the highest risk of short sleep duration. Those who currently or formerly smoked only traditional cigarettes also had significantly higher risk, unlike those who had only used e-cigarettes.

CONCLUSIONS

Survey respondents who used e-cigarettes were more likely to report short sleep duration, but only if they currently or formerly smoked traditional cigarettes. Those who used both products, regardless of whether current or former, were more likely to report short sleep duration than those who had used just one of these tobacco products.

A cross-sectional examination of the early-onset hypertensive disorders of pregnancy and industrial emissions of toxic metals using Kentucky birth records, 2008–2017

This cross-sectional study assessed geospatial patterns of early-onset hypertensive disorders of pregnancy (eHDP) in primiparous mothers and exposure to industrial emissions using geocoded residential information from Kentucky live (N = 210,804) and still (N = 1,247) birth records (2008–2017) and census block group estimates of aerosol concentrations of arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), selenium (Se), and zinc (Zi) from the Risk Screening Environmental Indicators (RSEI) model. A latent class analysis allowed for the identification of four district exposure classes—As, Cd, and Pb (12.6%); Se and Zi (21.4%); Pb and Cr (8%); and low or no exposures (57.9%). Women classified as having a high probability of exposure to both Pb and Cr had a statistically significantly greater prevalence of eHDP after adjusting for demographic factors (aPR = 1.22, 95% CI: 1.04, 1.44) relative to those with low or no exposure. Our findings contribute to the emerging literature on the association of metal exposures with pregnancy outcomes.

Examining Adult E-cigarette Use in Kentucky and Its Appalachian Region Using the Behavioral Risk Factor Surveillance System, 2016-2017

OBJECTIVES

Electronic cigarette (e-cigarette) use has increased steadily in the United States, but little research has examined its prevalence in states comprising Appalachia, a rural region known for high rates of tobacco use. This study assessed lifetime and current e-cigarette use among adults by sociodemographic characteristics, geographic region, and cigarette smoking in Kentucky, with a focus on the Appalachian region.

METHODS

We used data from the 2016-2017 Behavioral Risk Factor Surveillance System (BRFSS) surveys to calculate the prevalence of lifetime and current e-cigarette use, and we used weighted multivariable logistic regression analyses to examine the relative influence of other factors.

RESULTS

Among adults in Kentucky, 5.8% (95% CI, 5.2%-6.4%) were current e-cigarette users and 27.0% (95% CI, 25.9%-28.0%) were lifetime users, compared with state medians of 4.6% (95% CI, 4.0%-5.1%) and 21.4% (95% CI, 19.4%-23.5%) for the United States. Multivariable regression models showed similar patterns for all regions: higher prevalence odds of current e-cigarette use among adults aged 18-24, current conventional smokers, and adults unable to work. Generally, Appalachian residents of Kentucky did not have significantly higher rates of lifetime or current e-cigarette use as compared with other non-Appalachian residents of Kentucky. Hispanic residents of Appalachian Kentucky, however, had higher rates of e-cigarette use than Hispanic residents of other regions of Kentucky.

CONCLUSIONS

Rates of e-cigarette use were higher in Kentucky than in the United States but were not further elevated in Kentucky's Appalachian region. High rates of e-cigarette use among Hispanic residents of Appalachia indicate a need to focus future interventions in the region.

Geocoding precision of birth records from 2008 to 2017 in Kentucky, USA

Maternal address information captured on birth records is increasingly used to estimate residential environmental exposures during pregnancy. However, there has been limited assessment of the geocoding precision of birth records, particularly since the adoption of the 2003 standard birth certificate in 2015. To address this gap, this study evaluated the geocoding precision of live and stillbirth records of Kentucky residents over ten years, from 2008 through 2017. This study summarized the demographic characteristics of imprecisely geocoded records and, using a bivariate logistic regression, identified covariates associated with poor geocoding precision among three population density designations-metro, non-metro, and rural. We found that in metro areas, after adjusting for area deprivation, education, and the race, age and education of both parents, records for Black mothers had 48% lower odds of imprecise geocoding (aOR=0.52, 95% CI: 0.48, 0.56), while Black women in rural areas had 96% higher odds of imprecise geocoding (aOr=1.96, 95% CI: 1.68, 2.28). This study also found that over the study period, rural and non-metro areas began with a high proportion of imprecisely geocoded records (38% in rural areas, 19% in non-metro), but both experienced an 8% decline in imprecisely geocoded records over the study period (aOr=0.92, 95% CI: 0.92, 0.94). This study shows that, while geocoding precision has improved in Kentucky, further work is needed to improve geocoding in rural areas and address racial and ethnic disparities.

Exploring COVID-19 Case Fatality in Relation to the Prevalence of Chronic Conditions and Health Behaviors in Appalachian Kentucky

Background

Research has demonstrated that common chronic conditions, especially those related to cardiovascular health, are important risk factors for severe COVID-19 symptoms or hospitalization. Population prevalence rates of such conditions have not previously been examined in relation to COVID-19 case fatality rates in the Central Appalachian region.

Purpose

This study examined prevalence rates of selected chronic conditions and COVID-19 case fatality rates to determine whether the relationship between them is consistent across Appalachian and non-Appalachian regions of Kentucky.

Methods

Data from Kentucky's Behavioral Risk Factor Survey (KyBRFS) were used to calculate prevalence rates of asthma, diabetes, influenza vaccination, hypertension, obesity, having a personal doctor, physical inactivity, and cigarette smoking. Publicly available COVID-19 case and death counts by county were used to calculate incidence and case fatality rates. Units of analysis were 41 single- and multi-county areas developed to visualize KyBRFS prevalence rates. Analysis included t-tests to compare Appalachian and non-Appalachian regions, and correlations characterizing associations between COVID-19 case fatality and rates of chronic conditions and behaviors.

Results

Incidence and case fatality rates for COVID-19 were slightly lower in the Appalachian region, but not significantly. Significant correlations between COVID-19 case fatality and the prevalence of chronic conditions and behaviors were more common in the non-Appalachian region.

Implications

Case fatality rates in Appalachia appear lower than expected, given the high prevalence of important chronic conditions and behaviors known to be associated with poor COVID-19 outcomes. This phenomenon merits further research and should be considered by public health researchers when examining COVID-19 outcomes in Kentucky and neighboring states.

Estimating the Population Attributable Fraction of Asthma Due to Electronic Cigarette Use and Other Risk Factors Using Kentucky Behavioral Risk Factor Survey Data, 2016-2017

Introduction: Electronic nicotine delivery systems ENDS have become popular in the United States among both new users of nicotine and those seeking less harmful alternatives to traditional cigarettes. Users often perceive ENDS as being less harmful than traditional cigarettes. This study investigated the relationship between use of ENDS and asthma in a representative sample of adults. Methods: For this cross-sectional study, we used data from the Kentucky Behavioral Risk Factor Surveillance System telephone survey data from 2016-2017. Using a weighted multivariable logistic regression analysis, we identified important covariates to adjust for to calculate the population attributable fraction (PAF) of asthma due to ENDS and other modifiable risk factors factors (cigarette use, obesity, education, and employment). The confidence intervals for the PAFs were estimated using bootstrap methods of variance estimation. Results: We found that 10.6% of those aged 18-30 reported currently had asthma. After adjusting for noted covariates, ENDS use did not significantly increase the odds of asthma. In the final PAF model, the PAF of asthma due to ENDS was 0.4% (95% CI: -5.41, 6.21). Conclusion: While these findings suggest only modest effects of ENDS use on asthma prevalence, future research including older age groups and more long-term users might produce different results.

Using residential histories in case-control analysis of lung cancer and mountaintop removal coal mining in Central Appalachia

Population-based ecological and cross-sectional studies have observed high risk for several cancers in areas of Central Appalachia where mountaintop removal coal mines operate. Case-control studies could provide stronger evidence of such relationships, but misclassification of exposure is likely when based on current residence, since individuals could have inhabited several residences with varying environmental exposures over many years. To address this, we used residential histories for individuals enrolled in a previous case-control study of lung cancer to assess residential proximity to mountaintop removal coal mining over a 30-year period, using both survey data and proprietary data from LexisNexis, Inc. Supplementing the survey data with LexisNexis data improved precision and completeness of geographic coordinates. Final logistic regression models revealed higher odds of high exposure among cases. These findings suggest that living in close proximity to mountaintop removal coal mining sites could increase risk for lung cancer, after adjusting for other relevant factors.

Hollows as Sampling Units for Community-Based Participatory Research in Appalachia: The Mountain Air Project

BACKGROUND

In rural Appalachia, numerous geographical, historical, and socioeconomic barriers undermine health. We describe a community/academic partnership that leveraged local assets to implement an on-the-ground enumeration approach to enrolling participants, ultimately achieving an 82.1% response rate in a cross-sectional study of adult respiratory disease. We sought to discuss challenges addressed while establishing an accurate sample frame and a broadly accepted data collection procedure.

METHODS

Innovative and established epidemiologic methods (household enumeration) were combined within a community-based participatory research (CBPR) framework. Community members partnered with researchers to identify an appropriate, novel sampling unit: hollows. Members of two community advisory boards (CABs) provided extensive guidance, and community health workers (CHWs) administered surveys and spirometry from randomly selected households.

RESULTS

Most hollows (28/40) had participation rates of more than 80%. The sample (N = 972) was representative of the study area.

CONCLUSIONS

Investigators seeking to recruit hard-to-reach populations may consider on-the-ground enumeration guided by community partners.

Appalachian Environmental Health Literacy: Building Knowledge and Skills to Protect Health

Environmental health literacy (EHL) is an emerging, multidisciplinary field that promotes understanding of how environmental exposures can affect human health. After discussing the regional relevance of environmental health knowledge and skills, this article describes three ongoing Appalachian projects that are focused on measuring and building EHL.

Informatics Methods and Infrastructure Needed to Study Factors Associated with High Incidence of Pediatric Brain and Central Nervous System Tumors in Kentucky

Pediatric brain and central nervous system tumors (PBCNSTs) are the most common solid tumors and are the leading cause of disease-related death in US children. PBCNST incidence rates in Kentucky are significantly higher than in the United States as a whole, and are even higher among Kentucky's Appalachian children. To understand and eventually eliminate such disparities, population-based research is needed to gain a thorough understanding of the epidemiology and etiology of the disease. This multi-institutional population-based retrospective cohort study is designed to identify factors associated with the high incidence of PBCNST in Kentucky, leveraging the infrastructure provided by the Kentucky Cancer Registry, its Virtual Tissue Repository (VTR), and the National Institutes of Health Gabriella Miller Kids First Data Resource Center (DRC). Spatiotemporal scan statistics have been used to explore geographic patterns of risk measured by standardized incidence ratios (SIRs) with 95% confidence intervals. The VTR is being used to collect biospecimens for the population-based cohort of PBCNST tissues that are being sequenced by Center for Data Driven Discovery in Biomedicine (D3b) at the Children's Hospital of Philadelphia (CHOP) with support from the Kids First DRC. After adjusting for demographic factors, we assess their potential relationship to environmental factors. We have identified regions in north-central and eastern Appalachian Kentucky where children experienced a significant increased risk of developing PBCNST from 1995-2017 (SIR, 1.48; 95% CI, 1.34-1.62). The VTR has been successful in the collection of a population-based cohort of 215 PBCNST specimens. Timely establishment of legal agreements for data sharing and tissue acquisition proved to be challenging which has been somewhat mitigated by the adoption of national agreement templates. Coronavirus disease 2019 (COVID-19) severely limited the generation of sequencing results due to laboratory shutdowns. However, tissue specimens processed before the shutdown indicated that punches were inferior to scrolls for generating enough quality material for DNA and RNA extraction. Informatics infrastructures that were developed have demonstrated the feasibility of our approach to generate and retrieve molecular results. Our study shows that population-based studies using historical tissue specimens are feasible and practical, but require significant investments in technical infrastructures.

Spatiotemporal Analysis of Lung Cancer Histological Types in Kentucky, 1995-2014

Recent metabolic and genetic research has demonstrated that risk for specific histological types of lung cancer varies in relation to cigarette smoking and obesity. This study investigated the spatial and temporal distribution of lung cancer histological types in Kentucky, a largely rural state with high rates of smoking and obesity, to discern population-level trends that might reflect variation in these and other risk factors. The Kentucky Cancer Registry provided residential geographic coordinates for lung cancer cases diagnosed from 1995 through 2014. We used multinomial and discrete Poisson spatiotemporal scan statistics, adjusted for age, gender, and race, to characterize risk for specific histological types—small cell, adenocarcinoma, squamous cell, and other types—throughout Kentucky and compared to maps of risk factors. Toward the end of the study period, adenocarcinoma was more common among all population subgroups in north-central Kentucky, where smoking and obesity are less prevalent. During the same time frame, squamous cell, small cell, and other types were more common in rural Appalachia, where smoking and obesity are more prevalent, and in some high poverty urban areas. Spatial and temporal patterns in the distribution of histological types of lung cancer are likely related to regional variation in multiple risk factors. High smoking and obesity rates in the Appalachian region, and likely in high poverty urban areas, appeared to coincide with high rates of squamous cell and small cell lung cancer. In north-central Kentucky, environmental exposures might have resulted in higher risk for adenocarcinoma specifically.

Effect of Local Smoke-Free Ordinances on Smoking Prevalence in Kentucky, 2002-2009

OBJECTIVES

Many local communities in Kentucky, a state with one of the highest smoking prevalence rates in the United States, have enacted smoke-free ordinances that prohibit smoking in workplaces and enclosed buildings open to the public. Research has shown that such ordinances are clearly beneficial for public health, but their influence on smoking prevalence in the populations they cover remains unclear. This study explores the effect of local smoke-free ordinances on smoking prevalence in Kentucky.

METHODS

We used a database of smoke-free ordinances maintained by the Kentucky Center for Smoke-Free Policy, Kentucky Behavioral Risk Factor Surveillance System survey data, and US Census data. We estimated the proportion of Kentucky adults living in counties with smoke-free ordinances of varying strength; examined bivariate associations between smoke-free ordinances and smoking prevalence; and fit regression models that adjusted for various county-level demographic, socioeconomic, and geographic factors.

RESULTS

Smoking prevalence was approximately 5% lower in counties with smoke-free ordinances, even after adjusting for other relevant factors, including a trend in decreasing prevalence throughout the study region. There was a slight dose-response effect related to the strength of smoke-free ordinances after adjustment for these covariates. Smoke-free ordinances appear to have a modest effect on smoking prevalence across the span of several years.

CONCLUSIONS

Findings demonstrate that although smoking prevalence fell throughout the state during the study period, counties with smoke-free ordinances experienced a greater decline. Future research should examine the strength of smoke-free ordinances in greater detail to better understand their influence on smoking prevalence.

Collaborative response to arsenic-contaminated soil in an Appalachian Kentucky neighborhood

The aim of this study was to identify factors associated with an increased exposure to arsenic-contaminated soil in a Kentucky neighborhood as part of collaborative public health response. An exposure assessment survey was administered to residents and toenail clippings and soil samples analyzed for arsenic concentration. The associations between exposure variables and arsenic concentrations were evaluated using a multivariate-generalized estimating equation. An ecological assessment of cancer incidence in the community was also conducted using standardized incidence ratio maps. Median toenail arsenic was 0.48 micrograms/gram (µg/g), twice the expected regional level of 0.2 µg/g. Mean residence surface soil arsenic level was 64.8 ppm. An increase of 1 ppm of residence concentration was significantly associated with a 0.003 µg/g rise in toenail levels. Concentrations for respondents who engaged in digging were 0.68 µg/g significantly higher compared to individuals who did not. No significantly elevated rates of lung or bladder cancer were observed in the affected ZIP codes. Living in areas with high soil arsenic contamination might lead to (1) increased exposure; (2) elevated residence soil arsenic concentrations and (3) the action of digging in the soil was associated with elevated toenail arsenic levels. Based upon elevated soil levels identified, residents were recommended to move from the contaminated environment until remediation was complete. Additional recommendations included regular health-care follow-up.

Alcohol sale status and homicide victimization in Kentucky, 2005-2012: Is there a spatial association?

To date, the association between the alcohol sale status of decedents' residence and alcohol-related homicide victimization have not been studied as far as we know. The current study aims to: i) determine whether homicide victims who were residents of wet counties had higher odds of testing positive for alcohol than their counterparts in moist or dry counties after adjusting for confounders; ii) determine whether homicides and alcohol-related homicides tend to cluster spatially; iii) determine whether the aforementioned associations exist only in highly-populated counties. A multilevel logistic regression analysis was used to analyze the data on homicide victims in the Kentucky Violent Death Reporting System from 2005 to 2012. Spatial statistics were used to determine the spatial autocorrelation in rates of homicides and alcohol-related homicides. Overall, 944 homicide victims were included. The male to female ratio was 3:1. About 32.8% of homicide victims tested positive for alcohol. About 33.0% of homicide decedents who were residents in wet counties tested positive for alcohol compared to 32.5% of their counterparts in moist/dry counties. Residence in wet counties was associated with a statistically insignificant increase in the unadjusted odds ratio (OR) of alcohol-related homicide victimization (OR=1.20, 95% CI=0.81-1.77) as well as the adjusted odds (aOR=1.33, 95% CI=0.83-2.12). There was no association between population size and alcohol-related homicide rate.

A case-control study of trace-element status and lung cancer in Appalachian Kentucky

Appalachian Kentucky (App KY) leads the nation in lung cancer incidence and mortality. Trace elements, such as As, have been associated with lung cancers in other regions of the country and we hypothesized that a population-based study would reveal higher trace element concentrations in App KY individuals with cancer compared to controls. Using toenail and drinking water trace element concentrations, this study investigated a possible association between lung cancer incidence and trace-element exposure in residents of this region. This population-based case-control study had 520 subjects, and 367 subjects provided toenail samples. Additionally, we explored the relationship between toenail and fingernail trace-element concentrations to determine if fingernails could be used as a surrogate for toenails when patients are unable to provide toenail samples. We found that, contrary to our initial hypothesis, trace element concentrations (Al, As, Cr, Mn, Co, Fe, Ni, Cu, Se, and Pb) were not higher in cancer cases than controls with the exception of Zn where concentrations were slightly higher in cases. In fact, univariate logistic regression models showed that individuals with lower concentrations of several elements (Al, Mn, Cr, and Se) were more likely to have lung cancer, although only Mn was significant in multivariate models which controlled for confounding factors. While drinking water concentrations of Al, Cr and Co were positively related to cancer incidence in univariate models, only Co remained significant in multivariate models. However, since the drinking water concentrations were extremely low and not reflected in the toenail concentrations, the significance of this finding is unclear. We also found that fingernail concentrations were not consistently predictive of toenail concentrations, indicating that fingernails should not be used as surrogates for toenails in future studies.

Spatial Distribution of Partner-Seeking Men Who Have Sex With Men Using Geosocial Networking Apps: Epidemiologic Study

Background

Geosocial networking apps have made sexual partner-seeking easier for men who have sex with men, raising both challenges and opportunities for human immunodeficiency virus and sexually transmitted infection prevention and research. Most studies on men who have sex with men geosocial networking app use have been conducted in large urban areas, despite research indicating similar patterns of online- and app-based sex-seeking among men who have sex with men in rural and midsize cities.

Objective

The goal of our research was to examine the spatial distribution of geosocial networking app usage and characterize areas with increasing numbers of partner-seeking men who have sex with men in a midsize city in the South.

Methods

Data collection points (n=62) were spaced in 2-mile increments along 9 routes (112 miles) covering the county encompassing the city. At each point, staff logged into 3 different geosocial networking apps to record the number of geosocial networking app users within a 1-mile radius. Data were collected separately during weekday daytime (9:00 AM to 4:00 PM) and weekend nighttime (8:00 PM to 12:00 AM) hours. Empirical Bayesian kriging was used to create a raster estimating the number of app users throughout the county. Raster values were summarized for each of the county's 208 Census block groups and used as the outcome measure (ie, geosocial networking app usage). Negative binomial regression and Wilcoxon signed rank sum tests were used to examine Census block group variables (eg, median income, median age) associated with geosocial networking app usage and temporal differences in app usage, respectively.

Results

The number of geosocial networking app users within a 1-mile radius of the data collection points ranged from 0 to 36 during weekday daytime hours and 0 to 39 during weekend nighttime hours. In adjusted analyses, Census block group median income and percent Hispanic ethnicity were negatively associated with geosocial networking app usage for all 3 geosocial networking apps during weekday daytime and weekend nighttime hours. Population density and the presence of businesses were positively associated with geosocial networking app usage for all 3 geosocial networking apps during both times.

Conclusions

In this midsize city, geosocial networking app usage was highest in areas that were more population-dense, were lower income, and had more businesses. This research is an example of how geosocial networking apps’ geospatial capabilities can be used to better understand patterns of virtual partner-seeking among men who have sex with men.

Obesity, metabolic factors and risk of different histological types of lung cancer: A Mendelian randomization study

BACKGROUND

Assessing the relationship between lung cancer and metabolic conditions is challenging because of the confounding effect of tobacco. Mendelian randomization (MR), or the use of genetic instrumental variables to assess causality, may help to identify the metabolic drivers of lung cancer.

METHODS AND FINDINGS

We identified genetic instruments for potential metabolic risk factors and evaluated these in relation to risk using 29,266 lung cancer cases (including 11,273 adenocarcinomas, 7,426 squamous cell and 2,664 small cell cases) and 56,450 controls. The MR risk analysis suggested a causal effect of body mass index (BMI) on lung cancer risk for two of the three major histological subtypes, with evidence of a risk increase for squamous cell carcinoma (odds ratio (OR) [95% confidence interval (CI)] = 1.20 [1.01-1.43] and for small cell lung cancer (OR [95%CI] = 1.52 [1.15-2.00]) for each standard deviation (SD) increase in BMI [4.6 kg/m2]), but not for adenocarcinoma (OR [95%CI] = 0.93 [0.79-1.08]) (Pheterogeneity = 4.3x10-3). Additional analysis using a genetic instrument for BMI showed that each SD increase in BMI increased cigarette consumption by 1.27 cigarettes per day (P = 2.1x10-3), providing novel evidence that a genetic susceptibility to obesity influences smoking patterns. There was also evidence that low-density lipoprotein cholesterol was inversely associated with lung cancer overall risk (OR [95%CI] = 0.90 [0.84-0.97] per SD of 38 mg/dl), while fasting insulin was positively associated (OR [95%CI] = 1.63 [1.25-2.13] per SD of 44.4 pmol/l). Sensitivity analyses including a weighted-median approach and MR-Egger test did not detect other pleiotropic effects biasing the main results.

CONCLUSIONS

Our results are consistent with a causal role of fasting insulin and low-density lipoprotein cholesterol in lung cancer etiology, as well as for BMI in squamous cell and small cell carcinoma. The latter relation may be mediated by a previously unrecognized effect of obesity on smoking behavior.

Geographical Clusters and Predictors of Rabies in Three Southeastern States

The rabies virus causes progressive encephalomyelitis that is fatal in nearly 100% of untreated cases. In the United States, wildlife act as the primary reservoir for rabies; prevention, surveillance, and control costs remain high. The purpose of this study is to understand the current distribution of wildlife rabies in three southeastern states, with particular focus on raccoons as the primary eastern reservoir, as well as identify demographic and geographic factors which may affect the risk of human exposure. This ecologic study obtained county-level rabies surveillance data from state health departments and the United States Department of Agriculture Wildlife services for North Carolina, Virginia, and West Virginia from 2010 to 2013. A spatial statistical analysis was performed to identify county clusters with high or low rates of raccoon rabies in the three states. Potential demographic and geographic factors associated with these varying rates of rabies were assessed using a multivariable negative binomial regression model. In North Carolina, raccoons constituted 50% of positive tests, in Virginia, 49%, and in West Virginia, 50%. Compared to persons residing in West Virginia counties, persons in North Carolina counties had 1.67 times the risk of exposure (p < 0.0001) to a rabid raccoon and those in Virginia counties had 1.82 times the risk of exposure (p < 0.0001) to a rabid raccoon. Compared to those counties where farmland makes up less than 17% of the total area, persons residing in counties with 17-28% farmland had a 32% increased risk of exposure to a rabid raccoon. In counties with 28-39% farmland, there was an 84% increased risk of exposure. State, rurality, and percent of area designated as farmland were the best predictors of risk of raccoon rabies exposure. Further research is needed to better understand the effect of the oral rabies vaccine program in controlling the risk of human exposure to raccoon rabies.

Rural-Urban Differences in Alzheimer's Disease and Related Disorders Diagnostic Prevalence in Kentucky and West Virginia

PURPOSE

Older adults living in rural areas may face barriers to obtaining a diagnosis of Alzheimer's disease and related disorders (ADRD). We sought to examine rural-urban differences in prevalence of ADRD among Medicare beneficiaries in Kentucky and West Virginia, 2 contiguous, geographically similar states with large rural areas and aged populations.

METHODS

We used Centers for Medicare and Medicaid Services Public Use Files data from 2007 to 2013 to assess prevalence of ADRD at the county level among all Medicare beneficiaries in each state. Rural-Urban Continuum Codes were used to classify counties as rural or urban. We used Poisson regression to estimate unadjusted and adjusted prevalence ratios. Primary analyses focused on 2013 data and were repeated for 2007 to 2012. This study was completely ecologic.

FINDINGS

After adjusting for state, average beneficiary age, percent of female beneficiaries, percent of beneficiaries eligible for Medicaid in each county, Central Appalachian county, percent of age-eligible residents enrolled in Medicare, and percent of residents under age 65 enrolled in Medicare in our adjusted models, we found that 2013 ADRD diagnostic prevalence was 11% lower in rural counties (95% CI: 9%-13%).

CONCLUSIONS

Medicare beneficiaries in rural counties in Kentucky and West Virginia may be underdiagnosed with respect to ADRD. However, due to the ecologic design, and evidence of a younger, more heavily male beneficiary population in some rural areas, further studies using individual-level data are needed to confirm the results.

Abstract 2526: Coal mining and cancer risk: important gaps in public health knowledge

Coal fueled 42% of electricity generation in the US in 2011 with &gt;1 billion tons mined across 27 states. Considering that 33% of petroleum used in the US comes from Arab States and Venezuela, coal will remain a critical component of US energy policy with national production expected to increase 7.6% by 2035. Given the large spatial extent of coal bearing formations, substantial proportions of the population are now, with more likely to be, exposed to coal mining (CM) activities, e.g. dust from mining and processing, leachates from mine tailings, and smoke from coal combustion. While CM activities are known to release carcinogens such as crystalline silica dust, polyaromatic hydrocarbons, and trace elements (e.g. Cd, As), a systematic review of literature published since 1980 regarding resultant impacts upon cancer rates in potentially exposed populations is equivocal. Occupational studies are designed to provide data concerning the effects of acute or long term exposure. Of 11 such studies identified, 7 found an increased risk of cancer in coal miners (digestive/gastric, lung, all cancers) but 4 found no increased risk (gastric, lung, all cancers). Another 17 studies compared miners to other populations, or examined CM as a risk factor. Nine found associations between CM and increased cancer risk (bladder, gastric, larynx, lung, nasal, all cancers), but 8 found no increased risk (gastric, lung). Finally, 6 studies were identified which examined associations between CM and cancer in the general population. Three found associations between community cancer rates and CM, with those living near CM at increased risk (male colorectal, lung), 2 used spatial statistics to identify cancer clusters associated with CM (breast, lung, respiratory, all cancers), and 1 used community surveys to identify increased self-reported cancer in mining areas. While the strength of these latter studies is limited by weaknesses inherent in ecological and cross-sectional designs, evidence exists to support the biological plausibility that populations near CM activities are at increased risk. Environmental studies have shown that lignite bed leachates are associated with renal pelvic cancer and induce kidney cell culture proliferation; rodents captured from CM areas had greater DNA damage than non-exposed controls; and crystalline silica may be found in coal at high levels and released by burning. In sum, the data are too weak to conclude there is an increased risk of cancer to the general population, to identify which specific populations suffer that risk, or indicate which mitigation strategies may be effectively implemented. While prospective cohort studies might provide such data, the long lag time between exposure and cancer may preclude practicality and other measures of exposure (e.g. toenail clippings, wind patterns) and potential pre-cancerous cellular conditions (e.g. DNA methylation, histone modifications) should be investigated as interim outcomes.

Citation Format: Wiley D. Jenkins, Georgia Mueller, W. Jay Christian. Coal mining and cancer risk: important gaps in public health knowledge. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2526. doi:10.1158/1538-7445.AM2013-2526

Exploring geographic variation in lung cancer incidence in Kentucky using a spatial scan statistic: elevated risk in the Appalachian coal-mining region

OBJECTIVES

We examined geographic patterns of lung cancer incidence in Kentucky. Recent research has suggested that the coal-mining industry contributes to lung cancer risk in Appalachia. We focused on the southeastern portion of the state, which has some of the highest lung cancer rates in the nation.

METHODS

We implemented a spatial scan statistic to identify areas with lung cancer incidence rates that were higher than expected, after adjusting for age, gender, and smoking. The Kentucky Cancer Registry supplied information on cases (1995-2007). The U.S. Census (2000) and several years of Behavioral Risk Factor Surveillance System data (1996-2006) provided county-level population and smoking data. We compared the results with coal-mining data from the Mining Safety and Health Administration and public water utility data from the Kentucky Division of Water.

RESULTS

We identified three clusters of counties with higher-than-expected rates. Cluster 1 (relative risk [RR] = 1.21, p<0.01) included 12 counties in southeastern Kentucky. Cluster 2 (RR=1.17, p<0.01) included three nearby counties in the same region. Several of the 15 counties in Cluster 3 (RR=1.04, p=0.01) were part of the Louisville, Kentucky, or Cincinnati, Ohio, metropolitan areas. All of the counties in Clusters 1 and 2 produced significant amounts of coal.

CONCLUSION

Environmental exposures related to the coal-mining industry could contribute to the high incidence of lung cancer in southeastern Kentucky. Lack of evidence for this effect in western Kentucky could be due to regional differences in mining practices and access to public water utilities. Future research should collect biological specimens and environmental samples to test for the presence of trace elements and other lung carcinogens.

Viral hepatitis and injection drug use in Appalachian Kentucky: a survey of rural health department clients

OBJECTIVES

We identified correlates of exposure to hepatitis B and C viruses among health department clients in Appalachian Kentucky, a rural region noted for high poverty and low education. Additionally, we investigated risk factors for transmission, and the frequency of use of preventive measures.

METHODS

Patients screened for hepatitis B or C at four county health departments in Appalachian Kentucky were administered a routine prescreening questionnaire and an additional survey designed to obtain detailed personal and behavioral risk factor data. These data were linked to produce a more comprehensive dataset for analysis, including test results, which were attached to the prescreening questionnaire.

RESULTS

In total, 92 health department clients participated in the study survey. Of these, test results were available for 80 of the clients. Very few subjects who enrolled in this study tested positive for hepatitis B. Twelve out of 80 participants (15%) tested positive for previous exposure to hepatitis C. No participants reported having human immunodeficiency virus.

CONCLUSIONS

Transmission of hepatitis C in these rural Appalachian communities is predominantly due to injection drug use. Patients with hepatitis C exposure are similar in their demographic and risk profiles as those seen in urban areas and, despite small numbers, can have a serious impact on small, rural public health systems.

Acceptance of the HPV vaccine for adolescent girls: analysis of state-added questions from the BRFSS

PURPOSE

Previous research regarding human papillomavirus (HPV) awareness and vaccine acceptance has relied on convenience or other selected samples of the population. To assess the prevalence of HPV awareness and vaccine acceptance in Kentucky we added questions to the 2006 Kentucky Behavioral Risk Factor Survey System (BRFSS), a population-based survey of health behaviors.

METHODS

Women who participated in the statewide BRFSS were asked two HPV-related questions: one assessed previous awareness of HPV, and another assessed vaccine acceptance for girls 10 to 15 years old. We used crosstabulations and multivariate logistic regression to determine which factors were associated with HPV awareness and vaccine acceptance. Because the HPV vaccine Gardasil was approved in June 2006, we conducted an analysis of pre- and postapproval HPV awareness and vaccine acceptance. We also compared results across Appalachian and non-Appalachian counties, two distinct regions of Kentucky.

RESULTS

Overall, 57.6% of women had heard of HPV, and 70.2% accepted vaccination for girls. HPV awareness increased after Gardasil's approval, but the increase was much smaller among Appalachian women. Prevalence of vaccine acceptance was unchanged in both regions. Awareness of HPV was not associated with vaccine acceptance, and factors significantly associated with vaccine acceptance in multivariate analysis differed by Appalachian status.

CONCLUSIONS

This population-based survey of Kentucky women found relatively high vaccine acceptance for girls. Also, many respondents reported not knowing whether they accept vaccination, and factors associated with vaccine acceptance varied by Appalachian status. These findings suggest that acceptance of the HPV vaccine for girls may improve with targeted interventions.

Human papillomavirus vaccine: knowledge and attitudes in two Appalachian Kentucky counties

OBJECTIVE

A vaccine against common high-risk types of human papillomavirus (HPV) associated with cervical cancer risk was recently approved. We assessed women's acceptance of HPV vaccination for themselves and for adolescent girls, in an Appalachian population with cervical cancer incidence and mortality rates among the highest in the United States.

METHODS

We conducted a population-based, random-digit telephone survey of over 600 adult women residing in two Appalachian Kentucky counties. The analysis focused on questions of HPV vaccine acceptance, and their relationship to several factors.

RESULTS

The majority of women indicated an interest in HPV vaccination for themselves (85.2%), but they were less accepting of a vaccine being administrated to girls of ages 10-15 (67.6%). Women who were younger, lower-income and smokers were more likely to support vaccination.

CONCLUSIONS

Although a relatively high percentage of women found the HPV vaccination acceptable for their own use, there was less enthusiasm for supporting vaccination to girls. This finding is of concern since the vaccine is being recommended for adolescent girls and young women, prior to sexual initiation. Educational campaigns will be needed for a successful vaccine implementation.

Perceived risk and interest in screening for lung cancer among current and former smokers

Factors associated with perceived risk, interest in screening information, and interest in being screened for lung cancer were examined among current and recent former smokers. Cross-sectional data were analyzed from 585 current and former smokers who participated in 12-month follow-up telephone interviews as part of a population-based cessation intervention trial. Current smokers who were thinking about or preparing to quit were more likely to perceive risk of lung cancer and be interested in lung cancer screening information than those who were not motivated to quit or who were in the process of actively quitting or maintaining abstinence. Smokers who participate in lung cancer screening may be motivated to participate in a broad range of tobacco dependence treatment options.

Distribution of urinary selenium and arsenic among pregnant women exposed to arsenic in drinking water

Inorganic arsenic (In-As) is a well-known toxicant and carcinogen found naturally in surface and groundwater around the world. Exposure can cause skin lesions, adverse reproductive outcomes, and cancer. There are two main pathways of arsenic (As) metabolism in humans: the reduction reactions, and the oxidative methylation reactions, where methyl groups are attached to As compounds to form monomethylarsenate (MMA) and dimethylarsenate (DMA). MMA, DMA, and In-As are excreted in urine. Urinary levels of another metalloid, selenium (Se), have recently been shown to be associated with increased As excretion and altered metabolite distribution. This study investigates this association, using data collected in a larger prospective study of arsenic and reproductive effects in Chile. This analysis included 93 pregnant women from Antofagasta. Data on demographic, behavioral, and other characteristics were obtained via interviews conducted by trained midwives, and spot urine samples were analyzed for As and Se concentration using inductively coupled plasma-mass spectrometry (ICP-MS). Urinary Se levels were found to be correlated with urinary As levels in bivariate analysis (r = 0.68, P < 0.01). Multiple linear regression analyses revealed that higher urinary Se levels were associated with increased urinary As excretion, increased %DMA, and decreased %In-As. The results of this study suggest that in populations exposed to arsenic, Se intake may be correlated with urinary As excretion, and may alter As methylation.

Motorcycle helmets and head injuries in Kentucky, 1995-2000

Motorcycle crashes are common occurrences in Kentucky, and often result in injury or death. The use of motorcycle helmets may improve injury outcomes. Data collected from University of Louisville Hospital trauma center were used to investigate the association between motorcycle helmet use and traumatic brain injuries (TBI), severe head injuries, and acute care hospital charges. Multiple logistic and linear regression models were used for analysis. Motorcycle drivers who did not wear helmets were more likely to incur a TBI (OR = 4.33, 95% CI: 2.60-7.20), severe head injuries (OR = 4.36, 95% CI: 2.58-7.37), and higher acute care hospital charges (beta = $26,618, 95% CI: $8670-$44,565). Kentucky's failure to require mandatory helmet use may increase incidence of TBI and severe head injuries among motorcyclists, and cost state government millions of dollars to pay for care for uninsured or Medicaid patients.