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Objective. Some children in the United States continue to be exposed to levels of lead that increase their risk for lowered intellectual functioning and behavior problems. It is unclear whether chelation therapy can prevent or reverse the neurodevelopmental sequelae of lead toxicity. The objective of this study was to determine whether chelation therapy with succimer (dimercaptosuccinic acid) in children with referral blood lead levels between 20 and 44 [micro]g/dL (0.96-2.12 [micro]mol/L) at 12 to 33 months of age has neurodevelopmental benefits at age 7 years. Methods. The Treatment of Lead-Exposed Children (TLC) study is a randomized, double-blind, placebo-controlled trial that was conducted between September 1994 and June 2003 in Philadelphia, PA; Newark, NJ; Cincinnati, OH; and Baltimore, MD. Of 1854 referred children who were between the ages of 12 to 33 months and screened for eligibility, 780 were randomized to the active drug and placebo groups stratified by clinical center, body surface area, blood lead level, and language spoken at home. At 7 years of age, 647 subjects remained in the study. Participants were randomly assigned to receive oral succimer or placebo. Up to 3 26-day courses of succimer or placebo therapy were administered depending on response to treatment in those who were given active drug. Eighty-nine percent had finished treatment by 6 months, with all children finishing by 13 months after randomization. All participants received residential lead hazard control measures before treatment. TLC subjects also received a daily multivitamin supplement before and after treatment(s) with succimer or placebo. Scores on standardized neuropsychological measures that tap cognition, behavior, learning and memory, attention, and neuromotor skills were measured. Results. Chelation therapy with succimer lowered average blood lead levels for ~6 months but resulted in no benefit in cognitive, behavioral, and neuromotor endpoints. Conclusion. These new follow-up data confirm our previous finding that the TLC regimen of chelation therapy is not associated with neurodevelopmental benefits in children with blood lead levels between 20 and 44 [micro]g/dL (0.96-2.17 [micro]mol/L). These results emphasize the importance of taking environmental measures to prevent exposure to lead. Chelation therapy with succimer cannot be recommended for children with blood lead levels between 20 and 44 [micro]g/dL (0.96-2.12 [micro]mol/L). Pediatrics 2004;114:19-26; child, lead, environmental exposure, chelation therapy, succimer, cognition, clinical trials. ABBREVIATIONS. CDC, Centers for Disease Control and Prevention; TLC, Treatment of Lead-Exposed Children; NEPSY, Developmental Neuropsychological Assessment; CI, confidence interval., Before the availability of chelating drugs, as many as 45% of lead-poisoned children who presented with signs or symptoms of encephalopathy died, and more than one quarter of surviving patients [...]

Fine-particulate air pollution may increase mortality rates in cities that have high levels of this type of air pollution. Fine-particulate air pollution is a combination of solid and liquid particles that are 2.5 micrometers or less in diameter and that can be easily inhaled. The particles result mainly from fuel combustion and may be toxic. Researchers followed 8,111 adults in six cities for 14 to 16 years to determine the effect of air pollution and other health factors on mortality. Death was significantly associated with inhalable, fine or sulfate particle pollution. Pollution and cigarette smoking were strongly related to death due to lung cancer and cardiopulmonary disease. Mortality rates specific to the cities increased with increases in the average level of pollutants in the cities. Mortality rates in the most polluted cities were 26% higher than those in the least polluted cities.

Abstract Background We investigated whether lack of perceived neighborhood safety due to crime, or living in high crime neighborhoods was associated with incident mobility disability in elderly populations. We hypothesized that low-income elders and elders at retirement age (65 – 74) would be at greatest risk of mobility disability onset in the face of perceived or measured crime-related safety hazards. Methods We conducted the study in the New Haven Established Populations for Epidemiologic Studies of the Elderly (EPESE), a longitudinal cohort study of community-dwelling elders aged 65 and older who were residents of New Haven, Connecticut in 1982. Elders were interviewed beginning in 1982 to assess mobility (ability to climb stairs and walk a half mile), perceptions of their neighborhood safety due to crime, annual household income, lifestyle characteristics (smoking, alcohol use, physical activity), and the presence of chronic co-morbid conditions. Additionally, we collected baseline data on neighborhood crime events from the New Haven Register newspaper in 1982 to measure local area crime rates at the census tract level. Results At baseline in 1982, 1,884 elders were without mobility disability. After 8 years of follow-up, perceiving safety hazards was associated with increased risk of mobility disability among elders at retirement age whose incomes were below the federal poverty line (HR 1.56, 95% CI 1.02 – 2.37). No effect of perceived safety hazards was found among elders at retirement age whose incomes were above the poverty line. No effect of living in neighborhoods with high crime rates (measured by newspaper reports) was found in any sub-group. Conclusion Perceiving a safety hazard due to neighborhood crime was associated with increased risk of incident mobility disability among impoverished elders near retirement age. Consistent with prior literature, retirement age appears to be a vulnerable period with respect to the effect of neighborhood conditions on elder health. Community violence prevention activities should address perceived safety among vulnerable populations, such as low-income elders at retirement age, to reduce future risks of mobility disability.

Introduction: Intervention studies have been designed to change dietary and lifestyle factors associated with chronic diseases, but self-reported behavior change may incorporate intervention-related bias. This study examines plasma nutrient concentration and correlations with self-reports in the Healthy Directions intervention study. The Healthy Directions intervention studies were designed to increase multivitamin use, fruit and vegetable consumption, and physical activity in working-class, multiethnic populations., Methods: Participants in both studies completed interviewer-administered questionnaires that collected information on sociodemographic and health behavior characteristics. Postintervention blood samples were collected from 209 participants and pooled in pairs within study and within intervention group., Results: We found significantly higher plasma concentrations of retinol (P = .01) and alpha-carotene (P = .03) in the intervention than in the usual care group. Self-reported multivitamin users had significantly higher concentrations of retinol (P < .001), beta-carotene (P = .02), and alpha-tocopherol (P < .001). Those who reported four or more fruit and vegetable servings per day had higher lutein and zeaxanthin (P = .05) and beta-cryptoxanthin (P = .05) concentrations than those consuming fewer. Plasma nutrient concentrations were associated with reported multivitamin use and fruit and vegetable intake, but the correlations were generally higher in the usual care group., Conclusion: We found significant postintervention differences in plasma carotenoid and tocopherol concentrations by treatment group, multivitamin use, and fruit and vegetable intake. However, because we only obtained postintervention blood samples, we were unable to assess preintervention-to-postintervention changes in plasma nutrients. Self-reported intakes were significantly correlated with plasma nutrient concentrations, but the strength of the correlations differed by group, suggesting some intervention-related bias in the questionnaire responses.