Early Exposure to Cumulative Social Risk and Trajectories of Body Mass Index in Childhood.

BACKGROUND: Childhood social risk has been associated with increased risk of childhood obesity. However, little is known about early exposure of cumulative social risk on BMI percentile (BMIp) trajectories in early childhood. METHODS: Public data from the Fragile Families and Child Wellbeing Study were analyzed (N = 3809). Maternal reports of experiences of multiple social risk factors were obtained at age 1 and 3 assessments of children. Two cumulative social risk scores were calculated by summing social factors assessed at age 1 and at age 3. Child BMIp was assessed at ages 3, 5, and 9. Linear mixed models were used to examine the effect of cumulative social risk on sex-specific BMIp trajectories. RESULTS: Compared with girls experiencing low social risk at either age 1 or 3, girls experiencing high social risk (≥ 2 factors) at age 1 or 3 only had higher initial BMIp at age 3 [ß0 = 5.70 (95% confidence interval, CI: 0.15-1.26) and 1.37 (95% CI: -2.25 to 4.99), respectively] and had nonsignificantly greater BMIp growth rate [ß1 = 0.39 (95% CI: -0.86 to 1.63) and 0.32 (95% CI: -0.86 to 1.63)]. Girls experiencing high social risk at both ages had nonsignificantly but consistently lower BMIp [ß1 = -1.24 (95% CI: -2.93 to 0.46)]. In addition, girls experiencing a sum of ≥4 risk factors at both ages had lower BMIp growth rate [ß1 = -1.77 (95% CI: -3.39 to -0.15)] compared to girls experiencing no risk factor. No associations were observed among boys. CONCLUSIONS: Early exposure to cumulative social risk may have long-term impact on BMIp trajectories among girls, depending on timing of exposure. Understanding the effect of cumulative social risk in different contexts, including sex, chronicity, and timing of exposure, may have practical implications for informing effective intervention to combat childhood obesity.

Neighborhood Social Context and Individual Polycyclic Aromatic Hydrocarbon Exposures Associated with Child Cognitive Test Scores.

Childhood cognitive and test-taking abilities have long-term implications for educational achievement and health, and may be influenced by household environmental exposures and neighborhood contexts. This study evaluates whether age 5 scores on the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R, administered in English) are associated with polycyclic aromatic hydrocarbon (PAH) exposure and neighborhood context variables including poverty, low educational attainment, low English language proficiency, and inadequate plumbing. The Columbia Center for Children's Environmental Health enrolled African-American and Dominican-American New York City women during pregnancy, and conducted follow-up for subsequent childhood health outcomes including cognitive test scores. Individual outcomes were linked to data characterizing 1-km network buffers around prenatal addresses, home observations, interviews, and prenatal PAH exposure data from personal air monitors. Prenatal PAH exposure above the median predicted 3.5 point lower total WPPSI-R scores and 3.9 point lower verbal scores; the association was similar in magnitude across models with adjustments for neighborhood characteristics. Neighborhood-level low English proficiency was independently associated with 2.3 point lower mean total WPPSI-R score, 1.2 point lower verbal score, and 2.7 point lower performance score per standard deviation. Low neighborhood-level educational attainment was also associated with 2.0 point lower performance scores. In models examining effect modification, neighborhood associations were similar or diminished among the high PAH exposure group, as compared with the low PAH exposure group. Early life exposure to personal PAH exposure or selected neighborhood-level social contexts may predict lower cognitive test scores. However, these results may reflect limited geographic exposure variation and limited generalizability.