Modeling epilepsy disparities among ethnic groups in Philadelphia, PA

Identifying Area-Level Disparities in Human Papillomavirus Vaccination Coverage Using Geospatial Analysis

BACKGROUND

Human papillomavirus (HPV) is the most common sexually transmitted infection within the United States (US). Despite clinical agreement on the effectiveness and widespread availability of the prophylactic HPV vaccine, vaccination coverage in the US is suboptimal and varies by geographic region and area-level variables. The goals of this article were to model the variation in vaccination rates among boys and girls within ZIP Codes in Virginia, determine whether neighborhood sociodemographic variables explain variation in HPV vaccination, and identify areas with significantly depressed vaccination coverage.

METHODS

We used Bayesian hierarchical spatial regression models with statewide immunization registry data to consider the correlation in vaccination among boys and girls, as well as the spatial correlation in vaccination for each sex.

RESULTS

The results showed low vaccination coverage in our birth cohort (28.9% in girls and 23.8% in boys) relative to the national level (56.8% and 51.8%, respectively). Several area-level variables were significantly and positively associated with vaccination coverage, including population density, percentage of Hispanic population, and average number of vehicles. In addition, there were several areas of significantly lowered vaccination coverage, including predominantly rural ones, and overall large geographic disparities in HPV vaccination.

CONCLUSIONS

Determining the geospatial patterning and area-level factors associated with HPV vaccination within a prescribed geographic area helps to inform future planning efforts.

IMPACT

The results of this study will help inform future planning efforts for geographically targeted interventions and policies, as well as drive new research to implement clinical and community strategies to increase HPV vaccination.

Spatial Analysis of the Impact of a School-Level Youth Violence Prevention Program on Violent Crime Incidents in the Community

This study investigated the effect of a school-based violence prevention program on community rates of violence for youth aged 10 to 18 in three urban communities with high rates of crime and poverty. We evaluated the impact of the Olweus Bully Prevention Program (OBPP) combined with a family intervention using a multiple baseline design in which we randomized the order and timing of intervention activities across three schools. Outcomes were police reports of violent crime incidents involving offenders aged 10 to 18 years (N = 2859 incidents) across a 6-year period. We used Bayesian hierarchical regression modeling to estimate the reduction of youth violence in the census blocks of the intervention middle school zones. Models controlled for percent female head-of-household, median household income, and percent renter-occupied housing units. Block groups within the attendance zones of schools receiving the intervention had a reduced risk of violence compared with those that did not (relative risk = 0.83, 95% credible interval = 0.71, 0.99). Our findings suggest that the school-level intervention was associated with a significant reduction in community-level youth violence. Public health professionals, program planners, and policy-makers should be aware of the potential community-wide benefit of school-level interventions.

Decomposition of the US black/white inequality in premature mortality, 2010-2015: an observational study

OBJECTIVE

Decompose the US black/white inequality in premature mortality into shared and group-specific risks to better inform health policy.

SETTING

All 50 US states and the District of Columbia, 2010 to 2015.

PARTICIPANTS

A total of 2.85 million non-Hispanic white and 762 639 non-Hispanic black US-resident decedents.

PRIMARY AND SECONDARY OUTCOME MEASURES

The race-specific county-level relative risks for US blacks and whites, separately, and the risk ratio between groups.

RESULTS

There is substantial geographic variation in premature mortality for both groups and the risk ratio between groups. After adjusting for median household income, county-level relative risks ranged from 0.46 to 2.04 (median: 1.03) for whites and from 0.31 to 3.28 (median: 1.15) for blacks. County-level risk ratios (black/white) ranged from 0.33 to 4.56 (median: 1.09). Half of the geographic variation in white premature mortality was shared with blacks, while only 15% of the geographic variation in black premature mortality was shared with whites. Non-Hispanic blacks experience substantial geographic variation in premature mortality that is not shared with whites. Moreover, black-specific geographic variation was not accounted for by median household income.

CONCLUSION

Understanding geographic variation in mortality is crucial to informing health policy; however, estimating mortality is difficult at small spatial scales or for small subpopulations. Bayesian joint spatial models ameliorate many of these issues and can provide a nuanced decomposition of risk. Using premature mortality as an example application, we show that Bayesian joint spatial models are a powerful tool as researchers grapple with disentangling neighbourhood contextual effects and sociodemographic compositional effects of an area when evaluating health outcomes. Further research is necessary in fully understanding when and how these models can be applied in an epidemiological setting.

Mapping Geographic Variation in Infant Mortality and Related Black-White Disparities in the US

BACKGROUND

In the US, black infants remain more than twice as likely as white infants to die in the first year of life. Previous studies of geographic variation in infant mortality disparities have been limited to large metropolitan areas where stable estimates of infant mortality rates by race can be determined, leaving much of the US unexplored.

METHODS

The objective of this analysis was to describe geographic variation in county-level racial disparities in infant mortality rates across the 48 contiguous US states and District of Columbia using national linked birth and infant death period files (2004-2011). We implemented Bayesian shared component models in OpenBUGS, borrowing strength across both spatial units and racial groups. We mapped posterior estimates of mortality rates for black and white infants as well as relative and absolute disparities.

RESULTS

Black infants had higher infant mortality rates than white infants in all counties, but there was geographic variation in the magnitude of both relative and absolute disparities. The mean difference between black and white rates was 5.9 per 1,000 (median: 5.8, interquartile range: 5.2 to 6.6 per 1,000), while those for black infants were 2.2 times higher than for white infants (median: 2.1, interquartile range: 1.9-2.3). One quarter of the county-level variation in rates for black infants was shared with white infants.

CONCLUSIONS

Examining county-level variation in infant mortality rates among black and white infants and related racial disparities may inform efforts to redress inequities and reduce the burden of infant mortality in the US.

Adherence to antiepileptic drugs among diverse older Americans on Part D Medicare

INTRODUCTION

Older minority groups are more likely to have poor AED adherence. We describe adherence to antiepileptic drugs (AEDs) among older Americans with epilepsy.

METHODS

In retrospective analyses of 2008-2010 Medicare claims for a 5% random sample of beneficiaries augmented by minority representation, epilepsy cases in 2009 were those with ≥1 claim with ICD-9345.x or ≥2 with 780.3x, and ≥1 AED. New-onset cases had no such claims or AEDs in the year before the 2009 index event. We calculated the Proportion of Days Covered (PDC) (days with ≥1 AED over total follow-up days) and used logistic regression to estimate associations of non-adherence (PDC <0.8) with minority group adjusting for covariates.

RESULTS

Of 36,912 epilepsy cases (19.2% White, 62.5% African American (AA), 11.3% Hispanic, 5.0% Asian and 2% American Indian/Alaskan Native), 31.8% were non-adherent (range: 24.1% Whites to 34.3% AAs). Of 3706 new-onset cases, 37% were non-adherent (range: 28.7% Whites to 40.5% AAs). In adjusted analyses, associations with minority group were significant among prevalent cases, and for AA and Asians vs. Whites among new cases. Among other findings, beneficiaries from high-poverty ZIP codes were more likely to be non-adherent than their counterparts, and those in cost-sharing drug benefit phases were less likely to be non-adherent than those in deductible phases.

CONCLUSION

About a third of older adults with epilepsy have poor AED adherence; minorities are more likely than Whites. Investigations of reasons for non-adherence, and interventions to promote adherence, are needed with particular attention to the effect of cost-sharing and poverty.

An examination of disparities in cancer incidence in Texas using Bayesian random coefficient models

Disparities in cancer risk exist between ethnic groups in the United States. These disparities often result from differential access to healthcare, differences in socioeconomic status and differential exposure to carcinogens. This study uses cancer incidence data from the population based Texas Cancer Registry to investigate the disparities in digestive and respiratory cancers from 2000 to 2008. A Bayesian hierarchical regression approach is used. All models are fit using the INLA method of Bayesian model estimation. Specifically, a spatially varying coefficient model of the disparity between Hispanic and Non-Hispanic incidence is used. Results suggest that a spatio-temporal heterogeneity model best accounts for the observed Hispanic disparity in cancer risk. Overall, there is a significant disadvantage for the Hispanic population of Texas with respect to both of these cancers, and this disparity varies significantly over space. The greatest disparities between Hispanics and Non-Hispanics in digestive and respiratory cancers occur in eastern Texas, with patterns emerging as early as 2000 and continuing until 2008.

Spatial patterns of epilepsy-related emergency department visits in california

Background

Socio-demographic factors are associated with increased emergency department (ED) use among patients with epilepsy. However, there has been limited spatial analysis of such visits.

Design and methods

California ED visit at the patient ZIP Code level were examined using Kulldorf’s spatial scan statistic to identify clusters of increased risk for epilepsy-related visits. Logistic regression was used to examine the relative importance of patient socio-demographics, Census-based and hospital measures.

Results

During 2009-2011 there were 29,715,009 ED visits at 330 hospitals, of which 139,235 (0.5%) had epilepsy (International Classification of Disease-9 345.xx) as the primary diagnosis. Three large urban clusters of high epilepsy-related ED visits were centred in the cities of Los Angeles, Oakland and Stockton and a large rural cluster centred in Kern County. No consistent pattern by age, race/ethnicity, household structure, and income was observed among all clusters. Regression found only the Los Angeles cluster significant after adjusting for other measures.

Conclusions

Geospatial analysis within a large and geographically diverse region identified a cluster within its most populous city having an increased risk of ED visits for epilepsy independent of selected socio-demographic and hospital measures. Additional research is necessary to determine whether elevated rates of ED visits represent increased prevalence of epilepsy or an inequitable system of epilepsy care.

Variation in antiepileptic drug adherence among older patients with new-onset epilepsy

BACKGROUND

Medication adherence among patients with epilepsy remains a significant challenge, even for patients prescribed newer antiepileptic drugs (AEDs), leading to increased risks of seizures, hospitalizations, and higher treatment costs. Despite substantial research identifying numerous risk factors, the role of specific medications has been neglected.

OBJECTIVE

To analyze adherence to 9 different AEDs in a national clinical sample of elderly patients with new-onset epilepsy.

METHODS

Patients over age 66 receiving care in the Veterans Health Administration were eligible if they met criteria for new-onset epilepsy with AED monotherapy of at least 3 months. A cross-sectional study design was used to assess adherence as defined by the medication possession ratio (MPR) and a 90-day or longer medication gap. Multivariable logistic regression modeled each dichotomous adherence outcome as a function of clinical and demographic measures.

RESULTS

The sample (N = 6373) was primarily male (98%), white (79%), and exempt from medication copayments due to disability status; nearly 40% had a prior psychiatric or dementia diagnosis. Nearly half of the patients were poorly adherent, with rates ranging from 42% to 63% across AEDs. In multivariable models, patients on phenobarbital, valproate, and gabapentin were significantly less likely to be adherent on both outcomes, while lamotrigine and levetiracetam were positively associated with adherence per the MPR.

CONCLUSIONS

Adherence difficulty in this elderly cohort is attributable to several factors, yet specific AEDs substantially increased this risk. Drugs that produce adverse effects such as cognitive difficulty or weight gain may prove detrimental to maintaining appropriate adherence early in the treatment course. Given comparable efficacy among AEDs, providers should be aware that certain medications impart differential risks of poor adherence in older patients with epilepsy.

Health behaviors and conditions of persons with epilepsy: a bivariate analysis of 2006 BRFSS data

Using amalgamated Behavioral Risk Factor Surveillance System (BRFSS) data from nine states in 2006, this study examined the differences in demographics, health conditions, health behaviors, and quality of life among persons with active epilepsy (PWAE) and persons with a lifetime prevalence of epilepsy (PWLE), compared with persons without epilepsy (PWOE). Frequencies for PWAE, PWLE, and PWOE by selected health behaviors, health conditions, quality of life, and demographic variables were produced. Differences between persons with and without epilepsy were analyzed. Results indicated smoking and unemployment rates were significantly higher among PWLE/PWAE than among PWOE. PWLE/PWAE were also less likely than PWOE to report advanced educational attainment, and more likely to report suffering physical, mental, or emotional limitations that affected their activities in some way. Hispanics were less likely to report a lifetime or active prevalence of epilepsy than people without epilepsy. PWLE/PWAE report several differences in demographics, health conditions, health behaviors, and quality of life compared to people without epilepsy.