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Policy PointsThe White House Blueprint for Addressing the Maternal Health Crisis report released in June 2022 highlighted the need to enhance equitable access to maternity care.Nationwide hospital maternity unit closures have worsened the maternal health crisis in underserved communities, leaving many birthing people with few options and with long travel times to reach essential care.Ensuring equitable access to maternity care requires addressing travel burdens to care and inadequate digital access. Our findings reveal socioeconomically disadvantaged communities in the United States face dual barriers to maternity care access, as communities located farthest away from care facilities had the least digital access. Context: With the increases in nationwide hospital maternity unit closures, there is a greater need for telehealth services for the supervision, evaluation, and management of prenatal and postpartum care. However, challenges in digital access persist. We examined associations between driving time to hospital maternity units and digital access to understand whether augmenting digital access and telehealth services might help mitigate travel burdens to maternity care. Methods: This cross‐sectional study used 2020 American Hospital Association Annual Survey data for hospital maternity unit locations and 2020 American Community Survey five‐year ZIP Code Tabulation Area (ZCTA)–level estimates of household digital access to telecommunication technology and broadband. We calculated driving times of the fastest route from population‐weighted ZCTA centroids to the nearest hospital maternity unit. Rural‐urban stratified generalized median regression models were conducted to examine differences in ZCTA‐level proportions of household lacking digital access equipment (any digital device, smartphones, tablet), and lacking broadband subscriptions by spatial accessibility to maternity units. Findings: In 2020, 2,905 (16.6%) urban and 3,394 (39.5%) rural ZCTAs in the United States were located >30 minutes from the nearest hospital maternity units. Regardless of rurality, these communities farther away from a maternity unit had disproportionally lower broadband and device accessibility. Although urban communities have greater digital access to technology and broadband subscriptions compared to rural communities, disparities in the percentage of households with access to digital devices were more pronounced within urban areas, particularly between those with and without close proximity to a hospital maternity unit. Communities where nearest hospital maternity units were >30 minutes away had higher poverty and uninsurance rates than those with <15‐minute access. Conclusions: Socioeconomically disadvantaged communities face significant barriers to maternity care access, both with substantial travel burdens and inadequate digital access. To optimize maternity care access, ongoing efforts (e.g., Affordable Connectivity Program introduced in the 2021 Infrastructure Act), should bridge the gaps in digital access and target communities with substantial travel burdens to care and limited digital access. [ABSTRACT FROM AUTHOR]

Background: Direct estimates of rare disease prevalence from public health surveillance may only be available in a few catchment areas. Understanding variation among observed prevalence can inform estimates of prevalence in other locations. The Muscular Dystrophy Surveillance, Tracking, and Research Network (MD STARnet) conducts population-based surveillance of major muscular dystrophies in selected areas of the United States. We identified sources of variation in prevalence estimates of Duchenne and Becker muscular dystrophy (DBMD) within MD STARnet from published literature and a survey of MD STARnet investigators, then developed a logic model of the relationships between the sources of variation and estimated prevalence. Results: The 17 identified sources of variability fell into four categories: (1) inherent in surveillance systems, (2) particular to rare diseases, (3) particular to medical-records-based surveillance, and (4) resulting from extrapolation. For the sources of uncertainty measured by MD STARnet, we estimated each source's contribution to the total variance in DBMD prevalence. Based on the logic model we fit a multivariable Poisson regression model to 96 age–site–race/ethnicity strata. Age accounted for 74% of the variation between strata, surveillance site for 6%, race/ethnicity for 3%, and 17% remained unexplained. Conclusion: Variation in estimates derived from a non-random sample of states or counties may not be explained by demographic differences alone. Applying these estimates to other populations requires caution. [ABSTRACT FROM AUTHOR]

We develop a new Bayesian two-stage space-time mixture model to investigate the effects of air pollution on asthma. The two-stage mixture model proposed allows for the identification of temporal latent structure as well as the estimation of the effects of covariates on health outcomes. In the paper, we also consider spatial misalignment of exposure and health data. A simulation study is conducted to assess the performance of the 2-stage mixture model. We apply our statistical framework to a county-level ambulatory care asthma data set in the US state of Georgia for the years 1999-2008. [ABSTRACT FROM AUTHOR]

• Estimated 50% survival until age 23.7 years and 12.5 years after loss of ambulation • After loss of ambulation, glucocorticoid users had lower risk of death than non-users • Lower risk of death observed among ever-users of cough assist and scoliosis surgery • Non-Hispanic Black males had higher risk of death than Non-Hispanic White males • Cardiac medication and bilevel positive airway pressure were not associated with death Population-based estimates of survival among individuals with Duchenne muscular dystrophy (DMD) living in the United States are lacking. It is also unclear whether the association between glucocorticoid use and all-cause mortality persists in the context of other common treatments (cardiac medication, cough-assist, bilevel positive airway pressure, and scoliosis surgery) observed to delay mortality. Among 526 individuals identified by the Muscular Dystrophy Surveillance, Tracking, and Research Network, the estimated median survival time from birth was 23.7 years. Current glucocorticoid users had a lower hazard of mortality than non-users. Individuals who ever had scoliosis surgery had a lower hazard of mortality than individuals who did not have scoliosis surgery. Individuals who ever used cough assist had a lower hazard of mortality than individuals who never used cough assist. Non-Hispanic Black individuals had a higher hazard of mortality than non-Hispanic White individuals. No differences in hazards of mortality were observed between ever versus never use of cardiac medication and ever versus never use of bilevel positive airway pressure. The glucocorticoid observation is consistent with the 2018 Care Considerations statement that glucocorticoid use continues in the non-ambulatory phase. Our observations may inform the clinical care of individuals living with DMD. [ABSTRACT FROM AUTHOR]

The potential of using land cover/use categories as a proxy for soil metal concentrations was examined by measuring associations between Anderson land cover category percentages and soil concentrations of As, Pb, and Ba in ten sampling areas. Land cover category and metal associations with ethnicity and socioeconomic status at the United States Census 2000 block and block group levels also were investigated. Arsenic and Pb were highest in urban locations; Ba was a function of geology. Consistent associations were observed between urban/built up land cover, and Pb and poverty. Land cover can be used as proxy for metal concentrations, although associations are metal-dependent. [ABSTRACT FROM AUTHOR]

Importance: Previous studies have found a mixed association between Patient-Centered Medical Home (PCMH) designation and improvements in primary care quality indicators, including avoidable pediatric emergency department (ED) encounters. Whether these associations persist after accounting for the geographic locations of providers relative to where patients reside is unknown., Objective: To examine the association between geographic proximity to primary care providers versus hospitals and risk of avoidable and potentially avoidable ED visits among children with pre-existing diagnosis of attention-deficit/hyperactivity disorder or asthma., Methods: Retrospective cohort study of a panel of pediatric Medicaid claims data from the South Carolina from 2016-2018 for 2,959 beneficiaries having a pre-existing diagnosis of attention-deficit/hyperactivity disorder (ADD, ages 6-12) and 6,390 beneficiaries with asthma (MMA, ages 5-18), as defined using Healthcare Effectiveness Data and Information Set (HEDIS) performance measures. We calculated differences in avoidable and potentially avoidable ED visits by the beneficiary's PCMH attribution type and in relation to differences in proximity to their primary care providers versus hospitals. Outcomes were defined using the New York University Emergency Department Algorithm (NYU-EDA). Differences in ED visit risk were assessed using generalized estimation equations and compared using marginal effects models., Results: The 2.4 percentage point reduction in risk of avoidable ED visits among children in the ADD cohort who attended a PCMH versus those who did not increased to 3.9 to 7.2 percentage points as relative proximity to primary care providers versus hospitals improved (p < 0.01). Children in the ADD and MMA cohorts that were enrolled in a medical home, but did not attend one for primary care services exhibited a 5.4 and 3.0 percentage point increase in avoidable ED visit compared to children who were unenrolled and did not attend medical homes (p < 0.05), but these differences were only observed when geographic proximity to hospitals was more convenient than primary care providers. Mixed findings were observed for potentially avoidable visits., Conclusions: In several health care performance evaluations, patient-centered medical homes have not been found to reduce differences in hospital utilization for conditions that are treatable in primary care settings among children with chronic illnesses. Analytical approaches that also consider geographic proximity to health care services can identify performance benefits of medical homes. Expanding risk-adjustment models to also include geographic data would benefit ongoing quality improvement initiatives., Competing Interests: The authors have declared that no competing interests exist.

BACKGROUND: Before 2007, erythropoiesis-stimulating agents (ESAs) were the highest-expenditure drug in the Medicare system. In 2007, CMS issued a reimbursement policy change for ESAs used by cancer patients. However, empirical evidence is currently lacking to evaluate medical costs after the policy change, especially by sex and racial/ethnic groups. OBJECTIVE: To examine the impact of the Medicare reimbursement policy change and associated racial/ethnic and sex disparities on medical costs for cancer patients who were new users of ESAs. METHODS: This study was an exploratory retrospective treatment effectiveness study, which used SEER-Medicare linked data. A difference-in-difference design was used that incorporated a control group of patients with chronic kidney disease. A generalized linear model, with a log link and a gamma distribution, was used to examine medical costs. RESULTS: The Medicare reimbursement policy change was statistically significantly associated with an 11% (95% CI = 2%-20%) reduction in anemia-related costs, including a 10% (95% CI = 1%-19%) reduction in Medicare payment and an 18% (95% CI = 10%-26%) reduction in patient cost sharing. For total medical costs, the policy change was statistically significantly associated with a 12% (95% CI = 6%-18%) reduction, including an 11% (95% CI = 5%-18%) reduction in Medicare payment and a 14% (95% CI = 7%-20%) reduction in patient cost sharing. Medical costs were reduced in patients who were male and those who were White but remained the same for patients who were female and those who were Black, Hispanic, and other races or ethnicities. CONCLUSIONS: Anemia-related and total medical costs associated with ESAs used by cancer patients with chemotherapy-induced anemia were reduced after the Medicare reimbursement policy change. However, the policy change was only effective for patients who were male and those who were White. The policy change had no effect on patients who were female and those of racial/ethnic minorities. DISCLOSURES: This study was funded by the SPARC Research Grant. The funder had no role in any part of this study. This study used the linked SEER-Medicare database. The interpretation and reporting of the data are the sole responsibility of the authors. The authors have nothing to disclose.

Stressful life changes may tax people's adaptive capacity. We sought to determine if and when experiences of stressful life changes were associated with increased odds of adverse nutrition-related health outcomes among US Army soldiers relative to those who did not experience the same stressful life change. An additional aim was to determine which stressful life changes had the greatest association with these outcomes and if there were gender differences in the magnitude of the associations. Stressful life changes studied included: changes in marital status, combat deployment or return from deployment, relocation, adding a child, change in rank, change in occupation, and development of a physical limitation to duty. Using longitudinal data from the Stanford Military Data Repository, which represents all active-duty soldiers aged 17-62 between 2011 and 2014 (n = 827,126), we employed an event history analysis to examine associations between stressful life changes and a subsequent diagnosis of hyperlipidemia, substantial weight gain, and weight-related separation from the Army. Marriage was associated with an increase in the odds of substantial weight gain 3 months later for both men and women. Developing a physical duty limitation was associated with an increase in the odds of a hyperlipidemia diagnosis 2 months later for both men and women, as was substantial weight gain 2 months later. Stressful life changes were also associated with increased odds of nutrition-related health outcomes, although we found gender differences in the magnitude of the associations. Findings could be used to mitigate the effects of stress on health by health professionals.

Purpose: It is unclear how primary tumor location affects the pulmonary metastasis in colorectal cancer patients with different primary tumor locations. We aim to explore the relationship between primary tumor location and the incidence and prognosis of colorectal cancer patients with pulmonary metastasis at diagnosis., Methods: From Surveillance, Epidemiology, and End Results (SEER) database, 9920 out of 192,969 CRC patients were identified with pulmonary metastasis at diagnosis between 2010 and 2015. Patients were classified into three subsets according to primary tumor location. The incidence of pulmonary metastasis and median survival were calculated. Multivariable logistic and Cox regression were performed to identify the risk factors of pulmonary metastasis and prognosis., Results: The incidence of pulmonary metastasis was 5.14% in the entire colorectal cancer cohort and 25.66% in metastatic colorectal cancer patients. The median survival of those patients was 10 months. Rectal cancer patients exhibited the highest incidence of pulmonary metastasis, while they had the longest median survival (15 months). The right-sided colon cancer patients had the lowest incidence of pulmonary metastasis, but the shortest median survival (8 months). 61 to 80 years old, over 80, black, two or three extrapulmonary metastatic sites and CEA-positive had a negative influence both on the incidence and prognosis., Conclusions: The importance of primary tumor location in affecting the incidence of pulmonary metastasis and prognosis of colorectal cancer patients was highlighted in this study. Primary tumor location should be considered in clinical interference and personalized treatment for colorectal cancer patients with pulmonary metastasis.

Background: Central arteriovenous fistula (cAVF) has been investigated as a therapeutic measure for treatment-resistant hypertension in patients without advanced chronic kidney disease (CKD). There is considerable experience with the use of AVF for hemodialysis in patients with end-stage renal disease (ESRD). However, there is sparse data on the blood pressure (BP) effects of an AVF among patients with ESRD. We hypothesized that AVF creation would significantly reduce BP compared with patients who did not have an AVF among patients with ESRD before starting hemodialysis., Methods: BPs were compared during the 12 months before hemodialysis initiation in 399 patients with an AVF or AV graft created and 4,696 patients without either., Results: After propensity score matching 1:2 ratio (AVF to no AVF), repeated measures analysis of variance revealed significant reductions of -1.7 mm Hg systolic and -3.9 mm Hg diastolic BP 12 months in patients after AVF creation; P = 0.025 and P < 0.001, respectively, compared with those with no AVF., Conclusions: These findings suggest that AVF creation results in modest BP reduction in patients with pre-dialysis ESRD who require AVF for eventual hemodialysis therapy. Preferential diastolic BP reduction suggests that greater work is needed to characterize the ideal patient subset in which to use cAVF for treatment-resistant hypertension in those without advanced CKD., (© Published by Oxford University Press on behalf of American Journal of Hypertension Ltd 2019.)

Objective: The purpose of this study was to examine the trajectories of body mass index (BMI) in the first year of life and their determining factors., Methods: We used data from the Infant Feeding Practices Survey II restricted to children with 2 or more time points of BMI data during follow-up visits within the first year of life (n = 2320). Latent class growth analysis was used to identify distinct BMI trajectories. Using multinomial logistic regression, we examined the prenatal and early life determinants of the identified trajectories., Results: Three BMI trajectories were identified during the first year of life: "low-stable" (81.6%), "high-stable" (15.6%), and "rising" (2.8%) trajectories. Boys, preterm infants, infants born to overweight mothers, Hispanic mothers, non-Hispanic Black mothers, and mothers who smoked during pregnancy were significantly more likely to have high-stable versus low-stable trajectories. Infants born to non-Hispanic Black mothers were more likely to have a rising versus a low-stable trajectory. Household income ≥350% of the federal poverty level and full adherence to the guidelines of the American Academy of Pediatrics for both breastfeeding exclusivity and duration reduced the likelihood of infants being in the rising versus the low-stable trajectory., Conclusion: Distinct BMI trajectories were evident as early as infancy. The predictors of these trajectories offer information about high-risk groups, and important and preventable prenatal and postnatal risk factors for future intervention programs., (© 2018 Wiley Periodicals, Inc.)

Purpose: Studies have shown that children with muscular dystrophy are at increased risk for falls, however there is insufficient information about what predicts the first and subsequent events. The purpose of this study was to describe the experience of injury with emphasis on identifying risk factors for fall-related injuries., Methods: We studied 269 boys with muscular dystrophy describing their injury experience and identifying risk and protective factors associated with 281 non-simultaneous injuries and 127 falls that resulted in Emergency Department visits and/or inpatient hospitalization during the period 1998-2014. We used a Cox model to estimate the predictors of an initial fall and a zero-inflated Poisson model to identify the predictors for the number of falls., Results: Falls accounted for the greatest number of injury occurrences; The most frequent injury type was contusion. The factors that were protective for falls were steroid use, wheelchair use, or having a heart condition. Baseline age was negatively associated with the risk of having any fall, but not significantly related to subsequent falls., Conclusion: Wheelchair use and heart conditions associated with reduced risk of falls likely reflects decreased mobility. Clinicians should help families identify factors associated with falls among those who remain ambulatory.

Importance: The outcome of older patients with acute myeloid leukemia (AML) remains unsatisfactory. Recent studies have shown that HLA-mismatched microtransplant could improve outcomes in such patients., Objective: To evaluate outcomes in different age groups among older patients with newly diagnosed AML who receive HLA-mismatched microtransplant., Design, Setting, and Participants: This multicenter clinical study included 185 patients with de novo AML at 12 centers in China, the United States, and Spain in the Microtransplantation Interest Group. Patients were divided into the following 4 age groups: 60 to 64 years, 65 to 69 years, 70 to 74 years, and 75 to 85 years. The study period was May 1, 2006, to July 31, 2015., Exposures: Induction chemotherapy and postremission therapy with cytarabine hydrochloride with or without anthracycline, followed by highly HLA-mismatched related or fully mismatched unrelated donor cell infusion. No graft-vs-host disease prophylaxis was used., Main Outcomes and Measures: The primary end point of the study was to evaluate the complete remission rates, leukemia-free survival, and overall survival in different age groups. Additional end points of the study included hematopoietic recovery, graft-vs-host disease, relapse rate, nonrelapse mortality, and other treatment-related toxicities., Results: Among 185 patients, the median age was 67 years (range, 60-85 years), and 75 (40.5%) were female. The denominators in adjusted percentages in overall survival, leukemia-free survival, relapse, and nonrelapse mortality are not the sample proportions of observations. The overall complete remission rate was not significantly different among the 4 age groups (75.4% [52 of 69], 70.2% [33 of 47], 79.1% [34 of 43], and 73.1% [19 of 26). The 1-year overall survival rates were 87.7%, 85.8%, and 77.8% in the first 3 age groups, which were much higher than the rate in the fourth age group (51.7%) (P = .004, P = .008, and P = .04, respectively). The 2-year overall survival rates were 63.7% and 66.8% in the first 2 age groups, which were higher than the rates in the last 2 age groups (34.2% and 14.8%) (P = .02, P = .03, P < .001, and P < .001, respectively). The 1-year cumulative incidences of nonrelapse mortality were 10.2%, 0%, 3.4%, and 26.0% in the 4 age groups and 8.1% in all patients. The median times to neutrophil and platelet recovery were 12 days and 14 days after induction chemotherapy, respectively. Five patients had full or mixed donor engraftment, and 30.8% (8 of 26) of patients demonstrated donor microchimerism. Two patients (1.1%) developed severe acute graft-vs-host disease., Conclusions and Relevance: Microtransplant achieved a high complete remission rate in AML patients aged 60 to 85 years and higher 1-year overall survival in those aged 60 to 74 years.

Background: To evaluate the reliability and predictability of 49 socioeconomic indicators constructed from the annual and multiyear American Community Survey (ACS) data cycles for monitoring injury inequalities across the USA., Methods: Cross-sectional analysis of the 2006-2013 annual and multiyear county-level ACS data cycles. Indicator reliability was assessed using the margin of error and coefficient of variation (CV). Overlapping multiyear data cycles were assessed for statistical dependence in the estimates. Negative binomial regression models were constructed from a selection of the most reliable indicators over time and across all data cycles using all-cause unintentional and homicide-related mortality records from the National Center for Health Statistics (NCHS)., Results: Fewer than half of all indicators for each data cycle generated 'high reliability' CV estimates for at least 95% of all census counties. Indicator reliability did not linearly improve with increasing sample size afforded from the multiyear surveys. On average, changes in socioeconomic conditions for the same geographic areas were statistically significantly different (p<0.05) in 14% (rage 0-99%) to 16% (rage 0-93%) of all overlapping multiyear data cycles. ACS indicators that were among the most reliable across data cycles corroborated variable relationships derived using estimates from the 2000 decennial census and corresponding NCHS records for that year., Conclusions: Few of the socioeconomic indicators previously used to measure injury disparities are consistently reliable across all ACS data cycles. Researchers should be judicious when selecting consecutive multiyear data cycles to approximate changes in annual socioeconomic conditions. Among the indicators that are reliable, it is advisable to use estimates from the annual ACS data cycle as a crude barometer of injury inequalities and the multiyear files to confirm and add precedence to national trends every three and five years., Competing Interests: Competing interests: None declared., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Exposure to arsenic (As) or lead (Pb) has been associated with adverse health outcomes, and high-risk populations can be disproportionately exposed to these metals in soils. The objectives of this study were: to examine if predicted soil As and Pb concentrations at maternal residences of South Carolina (SC) low-income mothers differed based on maternal race (non-Hispanic black versus white), to examine whether differences in predicted residential soil As and Pb concentrations among black and white mothers differed by socioeconomic status (SES), and to examine whether such disparities persisted after controlling for anthropogenic sources of these metals, including direction from, and distance to industrial facilities. Kriged soil As and Pb concentrations were estimated at maternal residences in 11 locations in SC, and models with maternal race and individual and US Census block group level SES measures were examined. US Environmental Protection Agency Toxics Release Inventory (TRI) facility As and Pb releases categorized by distance and direction to block groups in which mothers resided were also identified, as were proxy measures for historic use of leaded gasoline (road density) and Pb-based paint (categories of median year home built by US Census block group). Consistent racial disparities were observed for predicted residential soil As and Pb concentrations, and the disparity was stronger for Pb than As (betas from adjusted models for black mothers were 0.12 and 2.2 for As and Pb, respectively, all p<0.006). Higher road density and older homes in block groups were more closely associated with higher predicted soil As and Pb concentrations than on-site releases of As and Pb categorized by facility location. These findings suggest that non-Hispanic black mothers in this study population had elevated residential As and Pb soil concentrations, after adjusting for SES, and that soil As and Pb concentrations were not associated with recent industrial releases., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: To examine the association of cardiorespiratory fitness (CRF) with risk of coronary heart disease (CHD) while controlling for an individual's Framingham Risk Score (FRS)-predicted CHD risk., Patients and Methods: The study included 29,854 men from the Aerobics Center Longitudinal Study, who received a baseline examination from January 1, 1979, to December 31, 2002. Coronary heart disease events included self-reported myocardial infarction or revascularization or CHD death. Multivariable survival analysis investigated the association between CRF, FRS, and CHD. Cardiorespiratory fitness was analyzed as both a continuous and a categorical variable. The population was stratified by "low" and "moderate or high" risk of CHD to test for differences in the FRS stratified by CRF., Results: Compared with men without incident CHD, men with incident CHD were older (mean age, 51.6 years vs 44.6 years), had lower average maximally achieved fitness (10.9 metabolic equivalent of tasks vs 12.0 metabolic equivalent of tasks [METs]), and were more likely to have moderate or high 10-year CHD risk (P<.001). Cardiorespiratory fitness, defined as maximal METs, exhibited a 20% lower risk of CHD (hazard ratio, 0.80; 95% CI, 0.77-0.83) for each 1-unit MET increase. Among men in the low CRF strata, individuals with moderate or high 10-year CHD risk, according to the FRS, had a higher CHD risk (hazard ratio, 6.55; 95% CI, 3.64-11.82) than men with low CHD risk according to the FRS., Conclusion: Clinicians should promote physical activity to improve CRF so as to reduce CHD risk, even to patients with otherwise low CHD risk., (Copyright © 2015 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)

In this study, the relationship between physical activity (PA) and 3 self-concept constructs (physical abilities, physical appearance, and general self-concept) was examined. Youth with type 1 diabetes (n = 304), type 2 diabetes (n = 49), and nondiabetic controls (n = 127) aged 10-20 years wore pedometers over 7 days. Youth completed the Self-Description Questionnaire and correlation coefficients were calculated. Mean steps/day were 7413 ± 3415, 4959 ± 3474 and 6870 ± 3521 for type 1, type 2 and control youth, respectively. Significant correlations were found between steps/day and perception of physical abilities (r = .29; r = .31; r = .31) for type 1, type 2, and control youth, respectively. The other correlations were not significant. Among youth with type 2 diabetes, steps/day were significantly correlated with physical appearance (r = .46). The positive correlation between PA and physical abilities suggests a reciprocal relationship between behavior and perception.

We undertook a community-level aggregate analysis in South Carolina, USA, to examine associations between mother-child conditions from a Medicaid cohort of pregnant women and their children using spatially interpolated arsenic (As) and lead (Pb) concentrations in three geographic case areas and a control area. Weeks of gestation at birth was significantly negatively correlated with higher estimated As (r(s) = -0.28, p = 0.01) and Pb (r(s) = -0.26, p = 0.02) concentrations in one case area. Higher estimated Pb concentrations were consistently positively associated with frequency of black mothers (all p < 0.02) and negatively associated with frequency of white mothers (all p < 0.01), suggesting a racial disparity with respect to Pb., (Copyright © 2012. Published by Elsevier Ltd.)

Background: Lead exposure in childhood lowers IQ scores, but its effect on children's behavior is less clear. Because IQ, per se, affects behavior, measuring the direct effect of lead requires measuring and then adjusting for IQ. In addition, either peak blood lead concentration, usually at 2 years old, or the lower blood lead level measured at school age may be the most relevant. Few studies have all of this information., Objectives: The purpose of this work was to differentiate the direct effect of lead on behavior and the indirect effect through IQ and to examine the strength of the association for peak and concurrent blood lead concentration., Methods: Data come from a clinical trial of the chelating drug succimer to prevent cognitive impairment in 780 urban 12- to 33-month-olds with blood lead concentrations of 20 to 44 microg/dL. The children were followed from ages 2 to 7 years. The trial data were analyzed as a prospective observational study., Results: Blood lead concentration at 2 years old was not associated with Conners' Parent Rating Scale-Revised scores at 5 years of age or Behavioral Assessment Systems for Children scores at 7 years of age. Blood lead level at 7 years of age had direct effects on the Behavioral Assessment Systems for Children behavioral symptoms index, externalizing, and school problems at age 7., Conclusions: Concurrent blood lead concentration was associated with externalizing and school problems scales at 7 years of age, and the effect was not entirely mediated through the effect of lead on IQ.