Dataset Information

Child Survival and Early Lifetime Exposures to Ambient Fine Particulate Matter in India: A Retrospective Cohort Study.

ABSTRACT:

Background

Ambient fine particulate matter [PM ≤2.5μm in aerodynamic diameter (PM2.5)] is a major health risk for children, particularly in South Asia, which currently experiences the highest PM2.5 levels globally. Nevertheless, there is comparatively little epidemiological evidence from this region to quantify the effects of PM2.5 on child survival.

Objectives

We estimated the association between PM2.5 exposure and child survival in India.

Methods

We constructed a large, retrospective, and nationally representative cohort of children <5 years of age, born between 2009-2016, from the publicly available, cross-sectional 2015-2016 Demographic Health Surveys in India. In utero and post-delivery lifetime average ambient PM2.5 exposures were estimated with data from satellite remote sensing, meteorology, and land use information (model R2= 0.82). We used Cox proportional hazards regression to estimate the association between both average in utero and post-delivery lifetime PM2.5 and all-cause child mortality, controlling for individual- and household-level covariates, seasonality, location, and meteorology.

Results

Over 7,447,724 child-months of follow-up, there were 11,559 deaths at <5 years of age reported by the children's mothers. The mean concentrations of 9-month in utero and post-delivery lifetime average ambient PM2.5 exposure were 71.1 μg/m3 (range: 20.9-153.5 μg/m3) and 73.7 μg/m3 (range: 14.0-247.3 μg/m3), respectively. Estimated child mortality adjusted hazard ratios were 1.023 [95% confidence interval (CI): 1.008, 1.038] and 1.013 (95% CI: 1.001, 1.026) per 10-μg/m3 increase of in utero and post-delivery lifetime PM2.5, with both exposures in the model.

Discussion

This study adds to the growing body of evidence about the adverse health effects of PM2.5 by demonstrating the association between exposure, both in utero and post-delivery, on child survival at the national level in India. Strategies to reduce ambient air pollution levels, including steps to minimize in utero and early life exposures, are urgently needed in India and other countries where exposures are above recommended guideline values. https://doi.org/10.1289/EHP8910.

SUBMITTER: Liao J

PROVIDER: S-EPMC8791069 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BackgroundEpidemiological studies report fairly consistent associations between various air pollution metrics and autism spectrum disorder (ASD), with some elevated risks reported for different prenatal and postnatal periods.ObjectivesTo examine associations between ASD and ambient fine particulate matter (PM2.5) and ozone concentrations during the prenatal period through the second year of life in a case-control study.MethodsASD cases (n = 428) diagnosed at Cincinnati Children's Hospital Medical Center were frequency matched (15:1) to 6420 controls from Ohio birth records. We assigned daily PM2.5 and ozone estimates for 2005-2012 from US EPA's Fused Air Quality Surface Using Downscaling model to each participant for each day based on the mother's census tract of residence at birth. We calculated adjusted odds ratios (aORs) using logistic regression across continuous and categorical exposure window averages (trimesters, first and second postnatal years, and cumulative measure), adjusting for maternal- and birth-related confounders, both air pollutants, and multiple temporal exposure windows.ResultsWe detected elevated aORs for PM2.5 during the 2nd trimester, 1st year of life, and a cumulative period from pregnancy through the 2nd year (aOR ranges across categories: 1.41-1.44, 1.54-1.84, and 1.41-1.52 respectively), and for ozone in the 2nd year of life (aOR range across categories: 1.29-1.42). Per each change in IQR, we observed elevated aORs for ozone in the 3rd trimester, 1st and 2nd years of life, and the cumulative period (aOR range: 1.19-1.27) and for PM2.5 in the 2nd trimester, 1st year of life, and the cumulative period (aOR range: 1.11-1.17).DiscussionWe saw limited evidence of linear exposure-response relationships for ASD with increasing air pollution, but the elevated aORs detected for PM2.5 in upper exposure categories and per IQR unit increases were similar in magnitude to those reported in previous studies, especially for postnatal exposures.

Project description:Background/objectivePoor air quality is implicated as a risk factor for cognitive impairment and dementia. Few studies have examined these associations longitudinally in well-characterized population-based cohorts with standardized annual assessment of both mild cognitive impairment (MCI) and dementia. We investigated the association between estimated ambient fine particulate matter (PM2.5 ) and risk of incident MCI and dementia in a post-industrial region known for historically poor air quality.Setting/participantsAdults aged 65+ years in a population-based cohort (n = 1572).MeasurementsCensus tract level PM2.5 from Environmental Protection Agency (EPA) air quality monitors; Clinical Dementia Rating (CDR)®.DesignWe estimated ambient PM2.5 exposure (μg/m3 , single-year and 5-year averages) by geocoding participants' residential addresses to census tracts with daily EPA PM2.5 measurements from 2002 to 2014. Using Bayesian spatial regression modeling adjusted for age, sex, education, smoking history, and household income, we examined the association between estimated PM2.5 exposure and risk of incident MCI (CDR = 0.5) and incident dementia (CDR ≥ 1.0).ResultsModeling estimated single-year exposure, each 1 μg/m3 higher ambient PM2.5 was associated with 67% higher adjusted risk of incident dementia (hazard ratio [HR] = 1.669, 95% credible interval [CI]: 1.298, 2.136) and 75% higher adjusted risk of incident MCI (HR = 1.746, 95% CI: 1.518, 2.032). Estimates were higher when modeling 5-year ambient PM2.5 exposure for incident dementia (HR = 2.082, 95% CI: 1.528, 3.015) and incident MCI (HR = 3.419, 95% CI: 2.806, 4.164).ConclusionsHigher estimated ambient PM2.5 was associated with higher risk of incident MCI and dementia, particularly when considering longer-term exposure, and independent of demographic characteristics and smoking history. Targeting poor air quality may be a reasonable population-wide intervention to reduce the risk of cognitive impairment in older adults, particularly in regions exceeding current recommendations for safe exposure to PM2.5 .

Project description:ImportanceIncreased levels of ambient fine particulate matter (PM2.5) air pollution are associated with increased risks for detrimental health outcomes, but risks for patients with kidney transplants (KTs) remain unknown.ObjectiveTo investigate the association of PM2.5 exposure with KT outcomes.Design, setting, and participantsThis retrospective cohort study was conducted using data on patients who received KTs from 2004 to 2016 who were identified in the national US transplant registry and followed up through March 2021. Multiple databases were linked to obtain data on PM2.5 concentration, KT outcomes, and patient clinical, transplant, and contextual factors. Data were analyzed from April 2020 through July 2021.ExposuresExposures included post-KT time-dependent annual mean PM2.5 level (in 10 μg/m3) and mean PM2.5 level in the year before KT (ie, baseline levels) in quartiles, as well as baseline annual mean PM2.5 level (in 10 μg/m3).Main outcomes and measuresAcute kidney rejection (ie, rejection within 1 year after KT), time to death-censored graft failure, and time to all-cause death. Multivariable logistic regression for kidney rejection and Cox analyses with nonlinear assessment of exposure-response for death-censored graft failure and all-cause death were performed. The national burden of graft failure associated with PM2.5 levels greater than the Environmental Protection Agency recommended level of 12 μg/m3 was estimated.ResultsAmong 112 098 patients with KTs, 70 522 individuals (62.9%) were older than age 50 years at the time of KT, 68 117 (60.8%) were men, and the median (IQR) follow-up was 6.0 (3.9-8.9) years. There were 37 265 Black patients (33.2%), 17 047 Hispanic patients (15.2%), 48 581 White patients [43.3%]), and 9205 patients (8.2%) of other race or ethnicity. The median (IQR) baseline PM2.5 level was 9.8 (8.3-11.9) μg/m3. Increased baseline PM2.5 level, compared with quartile 1 baseline PM2.5 level, was not associated with higher odds of acute kidney rejection for quartile 2 (adjusted odds ratio [aOR], 0.99; 95% CI, 0.92-1.06) but was associated with increased odds for quartile 3 (aOR, 1.11; 95% CI, 1.04-1.20) and quartile 4 (aOR, 1.13; 95% CI, 1.05-1.23). Nonlinear assessment of exposure-response for graft failure and death showed no evidence for nonlinearity. Increased PM2.5 levels were associated with increased risk of death-censored graft failure (adjusted hazard ratio [aHR] per 10 μg/m3 increase, 1.17; 95% CI, 1.09-1.25) and all-cause death (aHR per 10 μg/m3 increase, 1.21; 95% CI, 1.14-1.28). The national burden of death-censored graft failure associated with PM2.5 above 12 μg/m3 was 57 failures (95% uncertainty interval, 48-67 failures) per year among patients with KTs.Conclusions and relevanceThis cohort study found that PM2.5 level was an independent risk factor associated with acute rejection, graft failure, and death among patients with KTs. These findings suggest that efforts toward decreasing levels of PM2.5 concentration may be associated with improved outcomes after KT.

Project description:ImportanceOutdoor particulate matter 2.5 μm or less in diameter (PM2.5) is a ubiquitous environmental neurotoxicant that may affect the developing brain. Little is known about associations between PM2.5 and white matter connectivity.ObjectivesTo assess associations between annual residential PM2.5 exposure and white matter microstructure health in a US sample of children 9 to 10 years of age and to examine whether associations are specific to certain white matter pathways or vary across neuroimaging diffusion markers reflective of intracellular and extracellular microstructural processes.Design, setting, and participantsThis cross-sectional study, the Adolescent Brain and Cognitive Development (ABCD) Study, was composed of 21 study sites across the US and used baseline data collected from children 9 to 10 years of age from September 1, 2016, to October 15, 2018. Data analysis was performed from September 15, 2020, to June 30, 2021.ExposuresAnnual mean PM2.5 exposure estimated by ensemble-based models and assigned to the primary residential addresses at baseline.Main outcomes and measuresDiffusion-weighted imaging (DWI) and tractography were used to delineate white matter tracts. The biophysical modeling technique of restriction spectrum imaging (RSI) was implemented to examine total hindered diffusion and restricted isotropic and anisotropic intracellular diffusion in each tract. Hierarchical mixed-effects models with natural splines were used to analyze the associations between PM2.5 exposure and DWI.ResultsIn a study population of 7602 children (mean [SD] age, 119.1 [7.42] months; 3955 [52.0%] female; 160 [ 21.%] Asian, 1025 [13.5%] Black, 1616 [21.3%] Hispanic, 4025 [52.9%] White, and 774 [10.2%] other [identified by parents as American Indian/Native American or Alaska Native; Native Hawaiian, Guamanian, Samoan, other Pacific Islander; Asian Indian, Chinese, Filipino, Japanese, Korean, Vietnamese, or other Asian; or other race]), associations were seen between annual ambient PM2.5 and hemispheric differences in white matter microstructure. Hemisphere-stratified models revealed significant associations between PM2.5 exposure and restricted isotropic intracellular diffusion in the left cingulum, in the left superior longitudinal fasciculus, and bilaterally in the fornix and uncinate fasciculus. In tracts with strong positive associations, a PM2.5 increase from 8 to 12 μg/m3 was associated with increases of 2.16% (95% CI, 0.49%-3.84%) in the left cingulum, 1.95% (95% CI, 0.43%-3.47%) in the left uncinate, and 1.68% (95% CI, 0.01%-3.34%) in the right uncinate. Widespread negative associations were observed between PM2.5 and mean diffusivity.Conclusions and relevanceThe findings of this cross-sectional study suggest that annual mean PM2.5 exposure during childhood is associated with increased restricted isotropic diffusion and decreased mean diffusivity of specific white matter tracts, potentially reflecting differences in the composition of white matter microarchitecture.