A Segmented Regression Analysis of Household Income and Recurrent Falls Among Adults in a National Cohort Study

Falls can have life-altering consequences for older adults, including extended recovery periods and compromised independence. Higher household income may mitigate the risk of falls by providing financial resources for mobility tools, remediation of environmental hazards, and needed supports, or it may buffer the impact of an initial fall on subsequent risk through improved assistance and care. Household income has not had a consistently observed association with falls in older adults; however, a segmented association may exist such that associations are attenuated above a certain income threshold. In this study, we utilized segmented negative binomial regression analysis to examine the association between household income and recurrent falls among 2,302 participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study recruited between 2003 and 2007. Income-fall association segments separated by changes in slope were considered. Model results indicated a 2-segment association between household income and recurrent falls in the past year. In the range below the breakpoint, household income was negatively associated with the rate of recurrent falls across all age groups examined; in a higher income range (from $20,000-$49,999 to ≥$150,000), the association was attenuated (weaker negative trend) or reversed (positive trend). These findings point to potential benefits of ensuring that incomes for lower-income adults exceed the threshold needed to confer a reduced risk of recurrent falls.

Racialized economic segregation and potentially preventable hospitalizations among Medicaid/CHIP-enrolled children

OBJECTIVE

To examine geographic variation in preventable hospitalizations among Medicaid/CHIP-enrolled children and to test the association between preventable hospitalizations and a novel measure of racialized economic segregation, which captures residential segregation within ZIP codes based on race and income simultaneously.

DATA SOURCES

We supplement claims and enrollment data from the Transformed Medicaid Statistical Information System (T-MSIS) representing over 12 million Medicaid/CHIP enrollees in 24 states with data from the Public Health Disparities Geocoding Project measuring racialized economic segregation.

STUDY DESIGN

We measure preventable hospitalizations by ZIP code among children. We use logistic regression to estimate the association between ZIP code-level measures of racialized economic segregation and preventable hospitalizations, controlling for sex, age, rurality, eligibility group, managed care plan type, and state.

DATA EXTRACTION METHODS

We include children ages 0-17 continuously enrolled in Medicaid/CHIP throughout 2018. We use validated algorithms to identify preventable hospitalizations, which account for characteristics of the pediatric population and exclude children with certain underlying conditions.

PRINCIPAL FINDINGS

Preventable hospitalizations vary substantially across ZIP codes, and a quarter of ZIP codes have rates exceeding 150 hospitalizations per 100,000 Medicaid-enrolled children per year. Preventable hospitalization rates vary significantly by level of racialized economic segregation: children living in the ZIP codes that have the highest concentration of low-income, non-Hispanic Black residents have adjusted rates of 181 per 100,000 children, compared to 110 per 100,000 for children in ZIP codes that have the highest concentration of high-income, non-Hispanic white residents (p < 0.01). This pattern is driven by asthma-related preventable hospitalizations.

CONCLUSIONS

Medicaid-enrolled children's risk of preventable hospitalizations depends on where they live, and children in economically and racially segregated neighborhoods-specifically those with higher concentrations of low-income, non-Hispanic Black residents-are at particularly high risk. It will be important to identify and implement Medicaid/CHIP and other policies that increase access to high-quality preventive care and that address structural drivers of children's health inequities.

The Association between Changes in Built Environment and Changes in Walking among Older Women in Portland, Oregon

Some cross-sectional evidence suggests that the objectively measured built environment can encourage walking among older adults. We examined the associations between objectively measured built environment with change in self-reported walking among older women by using data from the Study of Osteoporotic Fractures (SOF). We evaluated the longitudinal associations between built environment characteristics and walking among 1253 older women (median age = 71 years) in Portland, Oregon using generalized estimating equation models. Built environment characteristics included baseline values and longitudinal changes in distance to the closest bus stop, light rail station, commercial area, and park. A difference of 1 km in the baseline distance to the closest bus stop was associated with a 12% decrease in the total number of blocks walked per week during follow-up (e^β = 0.88, 95% CI: 0.78, 0.99). Our study provided limited support for an association between neighborhood transportation and changes in walking among older women. Future studies should consider examining both objective measures and perceptions of the built environment.

Examining Associations between Adverse Childhood Experiences and Posttraumatic Stress Disorder Symptoms among Young Survivors of Urban Violence

Our study examines the association between Adverse Childhood Experience (ACE) exposure and posttraumatic stress disorder (PTSD) symptoms among survivors of violence. In this cross-sectional study, an ACE questionnaire and PTSD Checklist for DSM-5 (PCL-5) were completed by 147 participants ≤ 3 months after presenting to a Philadelphia, PA emergency department between 2014 and 2019 with a violent injury. This study treated ACEs, both separate and cumulative, as exposures and PTSD symptom severity as the outcome. Most participants (63.3%) met criteria for provisional PTSD, 90% reported experiencing ≥ 1 ACE, and 39% reported experiencing ≥ 6 ACEs. Specific ACEs were associated with increasing PCL-5 scores and increased risk for provisional PTSD. Additionally, as participants' cumulative ACE scores increased, their PCL-5 scores worsened (b = 0.16; p < 0.05), and incremental ACE score increases predicted increased odds for a positive provisional PTSD screen. Results provide further evidence that ACEs exacerbate the development of PTSD in young survivors of violence. Future research should explore targeted interventions to treat PTSD among survivors of interpersonal violence.

Spatial predictors of heavy metal concentrations in epiphytic moss samples in Seattle, WA

The use of bio-indicators is an emerging, cost-effective alternative approach to identifying air pollution and assessing the need for additional air monitoring. This community science project explores the use of moss samples as bio-indicators of the distribution of metal air particulates in two residential neighborhoods of the industrial Duwamish Valley located in Seattle, WA (USA). We applied geographically weighted regression to data from 61 youth-collected samples to assess the location-specific area-level spatial predictors of the concentrations of 25 elements with focus on five heavy metals of concern due to health and environmental considerations. Spatial predictors included traffic volume, industrial land uses, major roadways, the airport, dirt roads, the Duwamish River, impervious surfaces, tree canopy cover, and sociodemographics. Traffic volume surrounding sample locations was the most consistent positive predictor of increasing heavy metal concentration. Greater distance from the heavy-industry corridor surrounding the Duwamish River predicted lower concentrations of all metals, with statistically significant associations for chromium and lead in some areas. As the distance from dirt roads increased, the concentration of arsenic and chromium decreased significantly. Percent tree canopy within 200 m of sample locations was a significant protective factor for cadmium concentrations. In addition, percent people of color was significantly positively associated with increasing lead, chromium and nickel concentrations. Our findings underscore the potential influence of heavy industry and mobile sources on heavy metal concentrations, the buffering potential of trees in local environments, and persistent opportunity to improve environmental justice.

Prenatal Diet as a Modifier of Environmental Risk Factors for Autism and Related Neurodevelopmental Outcomes

PURPOSE OF REVIEW

Environmental chemicals and toxins have been associated with increased risk of impaired neurodevelopment and specific conditions like autism spectrum disorder (ASD). Prenatal diet is an individually modifiable factor that may alter associations with such environmental factors. The purpose of this review is to summarize studies examining prenatal dietary factors as potential modifiers of the relationship between environmental exposures and ASD or related neurodevelopmental outcomes.

RECENT FINDINGS

Twelve studies were identified; five examined ASD diagnosis or ASD-related traits as the outcome (age at assessment range: 2-5 years) while the remainder addressed associations with neurodevelopmental scores (age at assessment range: 6 months to 6 years). Most studies focused on folic acid, prenatal vitamins, or omega-3 fatty acids as potentially beneficial effect modifiers. Environmental risk factors examined included air pollutants, endocrine disrupting chemicals, pesticides, and heavy metals. Most studies took place in North America. In 10/12 studies, the prenatal dietary factor under study was identified as a significant modifier, generally attenuating the association between the environmental exposure and ASD or neurodevelopment. Prenatal diet may be a promising target to mitigate adverse effects of environmental exposures on neurodevelopmental outcomes. Further research focused on joint effects is needed that encompasses a broader variety of dietary factors, guided by our understanding of mechanisms linking environmental exposures with neurodevelopment. Future studies should also aim to include diverse populations, utilize advanced methods to optimize detection of novel joint effects, incorporate consideration of timing, and consider both synergistic and antagonistic potential of diet.

Spatially varying racial inequities in cardiovascular health and the contribution of individual- and neighborhood-level characteristics across the United States: The REasons for geographic and racial differences in stroke (REGARDS) study

Black-White inequities in cardiovascular health (CVH) pose a significant public health challenge, with these disparities also varying geographically across the US. There remains limited evidence of the impact of social determinants of health on these inequities. Using a national population-based cohort from the REasons for Geographic and Racial Differences in Stroke study, we assessed the spatial heterogeneity in Black-White differences in CVH and determined the extent to which individual- and neighborhood-level characteristics explain these inequities. We utilized a Bayesian hierarchical statistical framework to fit spatially varying coefficient models. Results showed overall and spatially varying inequities, where Black participants had significantly poorer CVH. The maps of the state level random effects also highlighted how inequities vary. The evidence produced in this study further highlights the importance of multilevel approaches - at the individual- and neighborhood-levels - that need to be in place to address these geographic and racial differences in CVH.

Association of Maternal-Clinician Ethnic Concordance With Latinx Youth Receipt of Family-Centered Care

IMPORTANCE

Disparities in medical home provisions, including receipt of family-centered care (FCC), have persisted for Latinx youths in the US.

OBJECTIVE

To examine the association between maternal-clinician ethnic concordance and receipt of FCC among US-born Latinx youths.

DESIGN, SETTING, AND PARTICIPANTS

A cross-sectional secondary analysis of data from the Medical Expenditure Panel Survey from January 1, 2010, to December 31, 2017, was conducted. Data analysis was performed from January 6 to February 3, 2020. Latinx youths (age, ≤17 years) born in the US who had a usual source of care and used care in the past year, their Latina mothers (age, 18-64 years), and youths' health care clinician characteristics (eg, race, ethnicity, and sex) were evaluated using χ2 tests and propensity-score matching methods.

MAIN OUTCOMES AND MEASURES

Maternal reports on whether their youths' clinician listened carefully to the parent, explained things in a way the parent could understand, showed respect, and spent enough time with the patient.

RESULTS

There were 2515 US-born Latinx youths with linked maternal characteristics during the study period; 51.67% (95% CI, 48.87%-54.45%) of the youths were male, mean (SD) age was 8.48 (0.17) years (30.86% [95% CI, 28.39%-33.44%] were between ages 5 and 9 years), 61.53% (95% CI, 57.15%-65.74%) had public insurance coverage, and 39.89% (95% CI, 32.33%-47.89%) had mothers who were ethnically concordant with the youths' medical care clinician. We found that for youths with maternal-clinician ethnic concordance, the probabilities of reporting FCC were significantly higher than they would have been in the absence of concordance: that the medical care clinician listened carefully to the parent (average treatment effect on the treated [ATET], 5.44%; 95% CI, 2.14%-8.74%), explained things in a way the parent could understand (ATET, 4.82%; 95% CI, 1.60%-8.03%), showed respect for what the parent had to say (ATET, 5.51%; 95% CI, 2.58%-8.45%), and spent enough time with the patient (ATET, 5.28%; 95% CI, 1.68%-8.88%).

CONCLUSIONS AND RELEVANCE

Given the increase of Latinx populations and the simultaneous shortage of underrepresented minority health care clinicians, the findings of this study suggest that increasing the number of clinicians from underrepresented minority backgrounds and ethnic-concordant parental-clinician relationships may help reduce disparities in receipt of medical home provision among US-born Latinx youths.

Posttraumatic Stress, Depression, and Sleep Among Young Survivors of Violence

Survivors of violence often suffer psychological harm in addition to physical wounds. This study explored (1) the prevalence of Posttraumatic Stress Disorder (PTSD) symptoms, depression symptoms, and disordered sleep among young, violently injured, emergency department patients; and (2) how PTSD and depression symptoms are associated with sleep quality. Clinical scales for PTSD (PCL-5), depression (PHQ-8), and sleep (PROMIS®) were completed by 88 survivors of violent assault (gunshot, stabbing or assault) one month or less after presenting to an urban emergency department. High proportions of participants met criteria for prospective PTSD (59.1%), major depression (44.3%) or disordered sleep (34.1%), with 27.3% meeting criteria for all three conditions. Poorer sleep quality was correlated with higher levels of depression symptoms and PTSD symptoms. Survivors of violence experience symptoms that may further impair their sleep and behavioral health. Emergency providers should ask survivors about sleep/trauma symptoms and consider referral to trauma-informed behavioral health care.

Examining the Geospatial Distribution of Health and Support Services for Transgender, Gender Nonbinary, and Other Gender Diverse People in New York City

A geospatial analysis of services that support transgender and gender diverse ("trans") people in New York City (NYC) was conducted to investigate associations with neighborhood-level sociodemographic characteristics. In June 2019, there were 5.3 services for every 100,000 of the general NYC population; controlling for other covariates, they were more commonly located in neighborhoods with larger populations of non-Hispanic Black (rate ratio [RR]=1.02, 95% confidence interval [CI]: 1.00-1.04), Hispanic/Latino (RR=1.03, 95% CI: 1.00-1.06), and gay/lesbian people (RR=1.53, 95% CI: 1.03-2.34). These findings suggest that the distribution of trans-focused services in NYC is proximal to communities that are most in need, but research should examine proximity to trans people specifically and distribution in nonurban areas.

Evaluating the informativeness of the Besag-York-Mollié CAR model

The use of the conditional autoregressive framework proposed by Besag, York, and Mollié (1991; BYM) is ubiquitous in Bayesian disease mapping and spatial epidemiology. While it is understood that Bayesian inference is based on a combination of the information contained in the data and the information contributed by the model, quantifying the contribution of the model relative to the information in the data is often non-trivial. Here, we provide a measure of the contribution of the BYM framework by first considering the simple Poisson-gamma setting in which quantifying the prior's contribution is quite clear. We then propose a relationship between gamma and lognormal priors that we then extend to cover the framework proposed by BYM. Following a brief simulation study in which we illustrate the accuracy of our lognormal approximation of the gamma prior, we analyze a dataset comprised of county-level heart disease-related death data across the United States. In addition to demonstrating the potential for the BYM framework to correspond to a highly informative prior specification, we also illustrate the sensitivity of death rate estimates to changes in the informativeness of the BYM framework.

Creating and sustaining effective pipeline initiatives to increase diversity in biostatistics: the ENAR Fostering Diversity in Biostatistics Workshop

Biostatisticians with advanced degrees are highly sought after. Employment opportunities in the fields of mathematics and statistics are expected to increase dramatically by 2028. Underrepresentation of minorities in biostatistics has been a persistent problem, yielding a demographic landscape that differs substantially from the general US population. In some instances, students may have the appropriate quantitative skills, but are unaware of biostatistics and in other instances, students may not yet have the appropriate quantitative background, but are intellectually capable and willing to shore up those skills once they learn about biostatistics as a viable, exciting career option. Therefore, in order to ensure robust scientific advancement, there must be a concerted effort to increase the pipeline of intellectually talented persons available with exposure to the appropriate quantitative skills who are interested in careers in biostatistics. The overarching goal of this paper is to discuss the development, implementation, and impact of a federally funded pipeline initiative aimed at increasing the number of underrepresented minorities successful in graduate training and professional careers in biostatistics as well as establishing effective mentoring and networking relationships. Our findings provide a roadmap for the development of sustainable initiatives to promote diversity in biostatistics and STEM fields more broadly.

Association of Maternal Citizenship and State-Level Immigrant Policies With Health Insurance Coverage Among US-Born Latino Youths

IMPORTANCE

The association of state-level immigrant policies with uninsurance among Latino youths remains unknown.

OBJECTIVE

To assess the association of state-level immigrant integration and criminalization policies with health insurance coverage among US-born Latino youths by maternal citizenship.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study analyzed secondary data from the American Community Survey, January 1, 2016, to December 31, 2018, for US-born Latino youths (age, ≤17 years) and their mothers (age, 18-64 years) as well as state-level indicators of immigrant integration and criminalization policies (in all 50 states and the District of Columbia).

EXPOSURES

Immigrant integration and criminalization policies.

MAIN OUTCOMES AND MEASURES

The main outcome was maternal reports of youth uninsurance status at the time of the American Community Survey interview. Variation in youth uninsurance by maternal citizenship, state immigrant integration policy context, and state immigrant criminalization policy context were examined. All analyses were conducted with weighted survey data.

RESULTS

Of the 226 691 US-born Latino youths (115 431 [50.92%] male; mean [SD] age, 7.66 [4.92] years) included in the study, 36.64% (95% CI, 36.21%-36.92%) had noncitizen mothers. Overall, 7.09% (95% CI, 6.78%-7.41%) of noncitizen mothers reported that their youths were uninsured compared with 4.68% (95% CI, 4.49%-4.88%) of citizen mothers. Of uninsured youths who resided in states with a low level of immigrant integration policies, 9.10% (8.22%-10.06%) had noncitizen mothers and 4.75% (95% CI, 4.19%-5.37%) had citizen mothers; of uninsured youths who resided in states with high criminalization policies, 9.37% (95% CI, 8.90%-9.87%) had noncitizen mothers and 5.91% (95% CI, 5.64%-6.20%) had citizen mothers. In states with few immigrant integration policies, the probability of uninsurance among youths with noncitizen mothers was 3.3% (95% CI, 2.3%-4.4%) higher than that among youths with citizen mothers. Among youths with noncitizen mothers, the difference in the probability of uninsurance between those residing in states with a low level vs a high level of immigrant integration policies was 2.1% (95% CI, 0.6%-3.6%). Among youths residing in states with high levels of immigrant criminalization policies, those with noncitizen mothers had a 2.6% (95% CI, 1.9%-3.0%) higher probability of being uninsured compared with those whose mothers were citizens. Among youths with noncitizen mothers, the difference in the probability of uninsurance between those who resided in a state with a low level vs a state with a high level of immigrant criminalization policies was 1.7% (95% CI, 0.7%-2.7%).

CONCLUSIONS AND RELEVANCE

The findings of this cross-sectional study suggest that among US-born Latino youths, disparities in uninsurance by maternal citizenship are associated with state-level immigrant integration and criminalization policies and that anti-immigrant policies may be associated with disparities in health care access for US-born Latino youths.

Association of maternal characteristics with latino youth health insurance disparities in the United States: a generalized structural equation modeling approach

Background

Disparities in access to care persist for Latino youth born in the United States (US). The association of maternal characteristics, such as maternal citizenship status and insurance coverage, on youth health insurance coverage is unclear and is important to examine given the recent sociopolitical shifts occurring in the US.

Methods

We analyzed pooled cross-sectional data from the 2010–2018 National Health Interview Survey to examine the association of Latina maternal citizenship status on maternal insurance coverage status and youth uninsurance among US-born Latino youth. Our study sample consisted of 15,912 US-born Latino youth (ages < 18) with linked mothers. Our outcome measures were maternal insurance coverage type and youth uninsurance and primary predictor was maternal citizenship status. Generalized structural equation modeling was used to examine the relationships between maternal characteristics (maternal citizenship, maternal insurance coverage status) and youth uninsurance.

Results

Overall, 7% of US-born Latino youth were uninsured. Just 6% of youth with US-born mothers were uninsured compared to almost 10% of those with noncitizen mothers. Over 18% of youth with uninsured mothers were uninsured compared to 2.2% among youth with mothers who had private insurance coverage. Compared to both US-born and naturalized citizen Latina mothers, noncitizen Latina mothers had 4.75 times the odds of reporting being uninsured. Once adjusted for predisposing, enabling, and need factors, maternal uninsurance was strongly associated with youth uninsurance and maternal citizenship was weakly associated with youth uninsurance among US-born Latino youth.

Conclusion

Maternal citizenship was associated with both maternal uninsurance and youth uninsurance among US-born Latino youth. Federal- and state-level health policymaking should apply a two-generational approach to ensure that mothers of children are offered affordable health insurance coverage, regardless of their citizenship status, thus reducing uninsurance among US-born Latino youth.

Assessing the spatial heterogeneity in black-white differences in optimal cardiovascular health and the impact of individual- and neighborhood-level risk factors: The Multi-Ethnic Study of Atherosclerosis (MESA)

Racial disparities in cardiovascular health (CVH) continue to remain a public health concern in the United States. We use unique population-based data from the Multi-Ethnic Study of Atherosclerosis cohort to explore the black-white differences in optimal CVH. Utilizing geographically weighted regression methods, we assess the spatial heterogeneity in black-white differences in optimal CVH and the impact of both individual- and neighborhood-level risk factors. We found evidence of significant spatial heterogeneity in black-white differences that varied within and between the five sites. Initial models showed decreased odds of optimal CVH for blacks that ranged from 60% to 70% reduced odds - with noticeable variation of these decreased odds within each site. Adjusting for risk factors resulted in reductions in the black-white differences in optimal CVH. Further understanding of the reasons for spatial heterogeneities in black-white differences in nationally representative cohorts may provide important clues regarding the drivers of these differences.

Exploring the Spatial Patterning in Racial Differences in Cardiovascular Health Between Blacks and Whites Across the United States: The REGARDS Study

Background

Cardiovascular health (CVH) disparities between blacks and whites have persisted in the United States for some time, and although there have been remarkable improvements in addressing cardiovascular disease, it still remains the leading cause of death in the United States. In addition, well‐documented disparities are unfortunately widening incidence gaps across certain regions of the United States. Our focus was on answering the following questions: (1) How much spatial heterogeneity exists in the racial differences in CVH between blacks and whites across this country? and (2) Is the spatial heterogeneity in the racial differences significantly explained by living in the Stroke Belt?

Methods and Results

To explore the spatial patterning in the racial differences in CVH between blacks and whites across the country, we used geographically weighted regression methods, which result in local estimates of the racial differences in CVH. Using data from the REGARDS (Reasons for Geographic and Racial Differences in Stroke) Study, we found significant spatial patterning in these racial differences, even beyond the well‐known Stroke Belt and Stroke Buckle. All of the estimated differences indicated blacks consistently having diminishing CVH compared with whites, where this difference was largely noted in pockets of the Stroke Belt and Stroke Buckle, in addition to moderate to large disparities noted in the Great Lakes region, portions of the Northeast, and along the West coast.

Conclusions

Efforts to improve CVH and ultimately reduce disparities between blacks and whites require culturally competent methods, with a strong focus on geography‐based interventions and policies.

Density of Medical Marijuana Dispensaries and Current Marijuana Use among Young Adult Marijuana Users in Los Angeles

Background: While tobacco and alcohol studies have focused on density of outlets as a determinant of consumption, research has begun examining the effects of medical marijuana (MM) dispensaries on marijuana use. Objectives: Examine the relationship between density of MM dispensaries and frequency of marijuana use among young adult medical marijuana patients (MMP) and nonpatient users (NPU). Methods: Young adult marijuana users (n = 329) aged 18- to 26-year old were sampled in Los Angeles in 2014-2015 and separated into MMP (n = 198) and NPU (n = 131). In 2014, 425 operational MM dispensaries were identified within the City of Los Angeles. Sequential multilevel Poisson random effect models examined density of MM dispensaries per square mile and 90 d marijuana use among MMP and NUP at the ZIP code level while controlling for demographic, behavioral, and community characteristics. Results: Density of MM dispensaries was not related to 90 d use of marijuana (days of use or hits per day) among either MMP or NPU. MMP reported significantly greater days of marijuana use in the past 90 d compared to NPU but no differences were found for hits per day. African-Americans reported significantly greater hits per day compared to whites. Hispanics reported significantly fewer hits per day compared to non-Hispanics. Conclusion: Concentration of MM dispensaries surrounding young adult marijuana users in Los Angeles was unrelated to days of marijuana use irrespective of having a MM recommendation or not. Rather, individual factors related to consumer choices and behaviors were more important in determining recent marijuana use among MMP and NPU.

A 4-Year Analysis of the Incidence of Injuries Among CrossFit-Trained Participants

Background:

High-intensity functional training (HIFT) is a new training modality that merges high-intensity exercise with functional (multijoint) movements. Even though others exist, CrossFit training has emerged as the most common form of HIFT. Recently, several reports have linked CrossFit training to severe injuries and/or life-threatening conditions, such as rhabdomyolysis. Empirical evidence regarding the safety of this training modality is currently limited.

Purpose:

To examine the incidence of injuries related to CrossFit participation and to estimate the rate of injuries in a large cross-sectional convenience sample of CrossFit participants from around the world.

Study Design:

Descriptive epidemiology study.

Methods:

A total of 3049 participants who reported engaging in CrossFit training between 2013 and 2017 were surveyed.

Results:

A portion (30.5%) of the participants surveyed reported experiencing an injury over the previous 12 months because of their participation in CrossFit training. Injuries to the shoulders (39%), back (36%), knees (15%), elbows (12%), and wrists (11%) were most common for both male and female participants. The greatest number of injuries occurred among those who participated in CrossFit training 3 to 5 days per week (χ² = 12.51; P = .0019). Overall, and based on the assumed maximum number of workout hours per week, the injury rate was 0.27 per 1000 hours (females: 0.28; males: 0.26), whereas the assumed minimum number of workout hours per week resulted in an injury rate of 0.74 per 1000 hours (females: 0.78; males: 0.70).

Conclusion:

Our findings suggest that CrossFit training is relatively safe compared with more traditional training modalities. However, it seems that those within their first year of training as well as those who engage in this training modality less than 3 days per week and/or participate in less than 3 workouts per week are at a greater risk for injuries.

Associations of Bar and Restaurant Smoking Bans With Smoking Behavior in the CARDIA Study: A 25-Year Study

Indoor smoking bans have often been associated with reductions in smoking prevalence. However, few studies have evaluated their association with within-person changes in smoking behaviors. We linked longitudinal data from 5,105 adults aged 18-30 years at baseline from the Coronary Artery Risk Development in Young Adults (CARDIA) Study (1985-2011) to state, county, and local policies mandating 100% smoke-free bars and restaurants by census tract. We used fixed-effects models to examine the association of smoking bans with within-person change in current smoking risk, smoking intensity (smoking ≥10 cigarettes/day on average vs. <10 cigarettes/day), and quitting attempts, using both linear and nonlinear adjustment for secular trends. In models assuming a linear secular trend, smoking bans were associated with a decline in current smoking risk and smoking intensity and an increased likelihood of a quitting attempt. The association with current smoking was greatest among participants with a bachelor's degree or higher. In models with a nonlinear secular trend, pooled results were attenuated (confidence intervals included the null), but effect modification results were largely unchanged. Findings suggest that smoking ban associations may be difficult to disentangle from other tobacco control interventions and emphasize the importance of evaluating equity throughout policy implementation.

Density of day cares in relation to reported pertussis incidence in Philadelphia

OBJECTIVES

Reported pertussis incidence has increased markedly in recent years. In addition to the documented increase in under-immunization and waning immunity, the increase may be related to the more frequent use of child care services by parents over the last few decades. Additionally, clustering of outbreaks may be related to neighborhood characteristics not previously identified.

STUDY DESIGN

We conducted a citywide case-control study of children in Philadelphia aged birth through six years, between 2001 and 2013. Cases were reported as probable pertussis diagnoses to the Health Department. Controls were sampled from the city's immunization information system and matched to the cases by date of birth.

METHODS

Multilevel logistic regression was used to isolate the independent contributions of individual and neighborhood risk factors and the corresponding relative odds of pertussis. The density of day cares in each neighborhood served as the main exposure and reported incident cases of confirmed and probable pertussis was the main outcome.

RESULTS

Between 2001 and 2013, 410 cases of confirmed and probable pertussis were included with four controls matched per case yielding a final sample of 2050 children from 45 Philadelphia neighborhoods. There was a 30% increase in the risk of pertussis based solely on the neighborhood where the children resided (median odds ratio 1.3, 95% credible interval 1.1, 1.6). The density of day cares in each neighborhood was unrelated to the distribution of pertussis cases.

CONCLUSIONS

Pertussis clustering was observed at the neighborhood level in Philadelphia, but was unrelated to the neighborhood's day care density. From a Health Department perspective, the highest risk neighborhoods should be targeted for vaccine campaigns and further research to identify the etiologic risk factors.

Cross-sectional and longitudinal associations of neighbourhood social environment and smoking behaviour: the multiethnic study of atherosclerosis

BACKGROUND

Social features of neighbourhood environments may influence smoking by creating a stressful environment or by buffering stress through social cohesion. However, the association of the overall neighbourhood social environment (NSE) with smoking, and the association of specific neighbourhood social factors with change in smoking behaviour over time, has rarely been examined.

METHODS

This study included 5856 adults aged 45-84 years from the Multi-Ethnic Study of Atherosclerosis (2000-2012, average follow-up: 7.8 years). Outcomes included current smoking status and smoking intensity (average number of cigarettes smoked per day among baseline smokers). NSE was assessed as a composite score composed of aesthetic quality, safety and social cohesion scales (derived from neighbourhood surveys). Generalised linear mixed models evaluated the association of baseline NSE (composite score and individual scales) with current smoking (modified Poisson models) and smoking intensity (negative binomial models) cross-sectionally and longitudinally.

RESULTS

Each SD increase in baseline NSE composite score was associated with 13% lower prevalence of smoking at baseline (adjusted prevalence ratio (aPR) 0.87 (95% CI 0.78 to 0.98). Neighbourhood safety and aesthetic quality were similarly associated with lower smoking prevalence (aPR 0.87 (0.78 to 0.97) and aPR 0.87 (0.77 to 0.99), respectively) but the association with social cohesion was weaker or null. No significant associations were observed for smoking intensity among baseline smokers. Baseline NSE was not associated with changes in smoking risk or intensity over time.

CONCLUSIONS

Results suggest that neighbourhood social context influences whether older adults smoke, but does not promote smoking cessation or reduction over time.

Marginalized zero-altered models for longitudinal count data

Count data often exhibit more zeros than predicted by common count distributions like the Poisson or negative binomial. In recent years, there has been considerable interest in methods for analyzing zero-inflated count data in longitudinal or other correlated data settings. A common approach has been to extend zero-inflated Poisson models to include random effects that account for correlation among observations. However, these models have been shown to have a few drawbacks, including interpretability of regression coefficients and numerical instability of fitting algorithms even when the data arise from the assumed model. To address these issues, we propose a model that parameterizes the marginal associations between the count outcome and the covariates as easily interpretable log relative rates, while including random effects to account for correlation among observations. One of the main advantages of this marginal model is that it allows a basis upon which we can directly compare the performance of standard methods that ignore zero inflation with that of a method that explicitly takes zero inflation into account. We present simulations of these various model formulations in terms of bias and variance estimation. Finally, we apply the proposed approach to analyze toxicological data of the effect of emissions on cardiac arrhythmias.

The spatio-temporal relationship between alcohol outlets and violence before and after privatization: A natural experiment, Seattle, Wa 2010-2013

Alcohol-related violence is a well-documented public health concern, where various individual and community-level factors contribute to this relationship. The purpose of this study is to examine the impact of a significant policy change at the local level, which privatized liquor sales and distribution. Specifically, we explored the relationship between alcohol and violence in Seattle, WA, 2010-2013, via hierarchical spatio-temporal disease mapping models. To measure and map this complex spatio-temporal relationship at the census block group level (n=567), we examined a variety of models using integrated nested Laplace approximations and used the deviance information criterion to gauge model complexity and fit. For each additional off-premises and on-premises alcohol outlet in a given census block group, we found a significant increase of 8% and 5% for aggravated assaults and 6% and 5% for non-aggravated assaults, respectively. Lastly, our maps showed variation in the estimated relative risks across the city of Seattle.

Pitch Characteristics Before Ulnar Collateral Ligament Reconstruction in Major League Pitchers Compared With Age-Matched Controls

BACKGROUND

Ulnar collateral ligament reconstruction (UCLR) is commonly performed in Major League Baseball (MLB) pitchers, but little is known about the preoperative pitch type and velocity characteristics of pitchers who go on to undergo UCLR.

HYPOTHESIS

Pitchers who required UCLR have thrown a greater percentage of fastballs and have greater pitch velocities compared with age-matched controls in the season before injury.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

MLB pitchers active during the 2002 to 2015 seasons were included. The UCLR group consisted of MLB pitchers who received UCLR between 2003 and 2015, utilizing the season before surgery (2002-2014) for analysis. The control group comprised age-matched controls of the same season. Players who pitched less than 20 innings in the season before surgery were excluded. Pitch types were recorded as percentage of total pitches thrown. Pitch velocities were recorded for each pitch type. Pitch type and pitch velocities during preoperative seasons for UCLR pitchers were compared with age-matched controls using univariate and multivariate models.

RESULTS

A total of 114 cases that went on to UCLR and 3780 controls were included in the study. Pitchers who went on to UCLR appear to have greater fastball, slider, curveball, changeup, and split-fingered fastball velocities; there were no significant differences in pitch selection between the 2 groups.

CONCLUSION

In the season before surgery, MLB pitchers who underwent UCLR demonstrated greater fastball, slider, curveball, changeup, and split-fingered fastball velocities, with no significant difference in pitch type.

Neighborhood context and Black heterosexual men's sexual HIV risk behaviors

The effects of neighborhood context on sexual risk behavior are understudied, particularly for Black heterosexual men who do not inject drugs or report heavy drug use. Evidence of a generalized HIV epidemic (>1 %) among Black heterosexuals in low-income urban U.S. communities underscores the importance of examining the effects of neighborhood context on Black heterosexual men's sexual risk, however. We used structural equation modeling to test the pathways between neighborhood context (neighborhood disorder, personal violence, neighborhood threats), depression, substance use, and sexual risk behavior. Participants were 526 self-identified Black heterosexual men, ages 18-45, recruited via randomized venue-based probability sampling in Philadelphia, PA. Analyses of model fit statistics from Mplus indicated statistically significant direct pathways between neighborhood context, depression, substance use, and sexual risk behavior. The total indirect effect of neighborhood context on sexual risk behavior through substance use was also significant. The study's results highlight a need for more research on neighborhood context and sexual HIV risk, and for multilevel interventions to address the effects of negative neighborhood context on Black heterosexual men's sexual HIV risk.

Characterizing the empirical distribution of prokaryotic genome n-mers in the presence of nullomers

Characterizing the empirical distribution of the frequency of n-mers is a vital step in understanding the entire genome. This will allow for researchers to examine how complex the genome really is, and move beyond simple, traditional modeling frameworks that are often biased in the presence of abundant and/or extremely rare words. We hypothesize that models based on the negative binomial distribution and its zero-inflated counterpart will characterize the n-mer distributions of genomes better than the Poisson. Our study examined the empirical distribution of the frequency of n-mers (6 ≤ n ≤ 11) in 2,199 genomes. We considered four distributions: Poisson, negative binomial, zero-inflated Poisson, and zero-inflated negative binomial (ZINB). The number of genomes that have nullomers in 6-, 7-, and 8-mers was 150, 602 and 2,012, respectively, whereas all of the genomes for the 9-, 10-, and 11-mers had nullomers. In each n-mer considered, the negative binomial model performed the best for at least 93% of the 2,199 genomes; however, a small percentage (i.e., <7%) of the genomes did prefer the ZINB. The negative binomial and zero-inflation distributions extend the traditional Poisson setting and are more flexible in handling overdispersion that can be caused by an increase in nullomers. In an effort to characterize the distribution of the frequency of n-mers, researchers should also consider other discrete distributions that are more flexible and adjust for possible overdispersion.

Injuries among children with autism spectrum disorder

OBJECTIVE

We compared risk of injury among children with autism spectrum disorder (ASD) to those without ASD, adjusting for demographic and clinical characteristics.

METHODS

We used claims data from 2001 to 2009 from a commercial health plan in the United States. A validated ASD case identification algorithm identified 33,565 children (ages 0-20 years) with ASD and 138,876 children without. Counting process models tested the association between ASD status and injury episodes with separate regressions run for children during different age periods.

RESULTS

Unadjusted results demonstrated that children with ASD had a 12% greater injury risk than children without ASD (hazard ratio [HR] = 1.119; P < .001). After including demographic variables, the HR was 1.03 (P < .05); after controlling for co-occurring conditions, such as seizures, depression, etc, HR decreased to 0.889 (P < .001). For the age period analysis, HR values were as follows: for 0 to 2 years, HR 1.141; 3 to 5 years, HR 1.282; 6 to 10 years, HR not significant; and 11 to 20 years, HR 0.634 (P < .05 for all significant results).

CONCLUSIONS

Children with ASD have more injuries than children without ASD. After controlling for demographic factors and co-occurring conditions, children with ASD are at lower risk of injury, suggesting that co-occurring conditions or the ways these conditions interact with ASD is related to injuries. Clinicians should understand that injury risk in children with ASD may be driven by co-occurring conditions. Treating these conditions could thus decrease injury risk as well as have other benefits. Injury prevention interventions are especially warranted for younger children with ASD and those with seizures, depression, visual impairment, or attention-deficit disorders.

Mobility, disability, and social engagement in older adults

OBJECTIVE

To examine cross sectional associations between mobility with or without disability and social engagement in a community-based sample of older adults.

METHODS

Social engagement of participants (n = 676) was outside the home (participation in organizations and use of senior centers) and in home (talking by phone and use of Internet). Logistic or proportional odds models evaluated the association between social engagement and position in the disablement process (no mobility limitations, mobility limitations/no disability, and mobility limitations/disability).

RESULTS

Low mobility was associated with lower level of social engagement of all forms (Odds ratio (OR) = 0.59, confidence intervals (CI): 0.41-0.85 for organizations; OR = 0.67, CI: 0.42-1.06 for senior center; OR = 0.47, CI: 0.32-0.70 for phone; OR = 0.38, CI: 0.23-0.65 for Internet). For social engagement outside the home, odds of engagement were further reduced for individuals with disability.

DISCUSSION

Low mobility is associated with low social engagement even in the absence of disability; associations with disability differed by type of social engagement.

Alcohol beverage control, privatization and the geographic distribution of alcohol outlets

Background

With Pennsylvania currently considering a move away from an Alcohol Beverage Control state to a privatized alcohol distribution system, this study uses a spatial analytical approach to examine potential impacts of privatization on the number and spatial distribution of alcohol outlets in the city of Philadelphia over a long time horizon.

Methods

A suite of geospatial data were acquired for Philadelphia, including 1,964 alcohol outlet locations, 569,928 land parcels, and school, church, hospital, park and playground locations. These data were used as inputs for exploratory spatial analysis to estimate the expected number of outlets that would eventually operate in Philadelphia. Constraints included proximity restrictions (based on current ordinances regulating outlet distribution) of at least 200 feet between alcohol outlets and at least 300 feet between outlets and schools, churches, hospitals, parks and playgrounds.

Results

Findings suggest that current state policies on alcohol outlet distributions in Philadelphia are loosely enforced, with many areas exhibiting extremely high spatial densities of outlets that violate existing proximity restrictions. The spatial model indicates that an additional 1,115 outlets could open in Philadelphia if privatization was to occur and current proximity ordinances were maintained.

Conclusions

The study reveals that spatial analytical approaches can function as an excellent tool for contingency-based “what-if” analysis, providing an objective snapshot of potential policy outcomes prior to implementation. In this case, the likely outcome is a tremendous increase in alcohol outlets in Philadelphia, with concomitant negative health, crime and quality of life outcomes that accompany such an increase.