Synergistic Effects of air Pollution and Neighborhood Violence on Epilepsy and Seizure in Young Children

• In Event: Inequities in Children’s Environmental Exposures: Integrating Toxicant, Social, and Structural Influences on Children’s Physical Health

Abstract

BACKGROUND AND AIM: Psychosocial stress and air pollution are being increasingly linked to multiple neurodevelopmental disorders, with potential synergistic effects. However, research investigating their impact on epilepsy and seizures — disorders suggested to be of developmental origin — is scarce. In this presentation, Dr. Clougherty will present nascent results examining combined effects of acute exposures to multiple pollutants and neighborhood violent crime (a critical urban psychosocial stressor) on epilepsy and seizure events among young children (0-4 years) in New York City.
METHODS: Using conditional logistic regression in a time-stratified, case-crossover design, we quantified percent excess risk of epilepsy or seizure event per 10-unit increase in daily exposures to PM2.5, NO2, SO2, and O3. Data on epilepsy/ seizure cases (n = 28,385), presenting at NYC emergency departments, 2005 to 2011, was obtained from New York Statewide Planning and Research Cooperative System. For each case, daily residence-specific pollution and temperature exposures were estimated using data from NYC Community Air Survey, and daily EPA pollution and NOAA weather data. Point-level NYPD data on felony crime events was aggregated by census tract, and annual average rates calculated per 10,000 residential population. Separate models were fit for each pollutant across lag days 0 to 6, controlling for case-day co-pollutants, temperature, and humidity, after sensitivity-testing multiple adjustment strategies. Variation in pollution and temperature effects across quintiles of crime rates was assessed.
RESULTS: We found the strongest main effects for PM2.5, particularly on lag days 1 [β = 2.93 (0.63, 5.28)], lag day 2 [β = 1.79 (-0.28, 3.90)], and lag day 3 [β = 2.47 (0.44, 4.54)]. NO2, SO2, and O3 effects were statistically non-significant. Annual violent crime rates modified PM2.5 effects in the opposite-to-hypothesized direction, with generally stronger associations in lower-violence quintiles.
CONCLUSIONS: Acute PM2.5 exposures may be associated with pediatric seizure risk, possibly via inflammatory mechanisms. Greater apparent effects in the lowest violence communities require further investigation, but may be attributable, in part, to saturation effects in socio-environmental stressor synergism. That is, in communities with very high exposures to severe social stressors (e.g., violence), we may observe particularly high rates of poor child health outcomes, and marginal effects of pollution or temperature may no longer be observable.

Authors

• Jane E. Clougherty, Drexel University
  Presenting Author

• Rachit Sharma, Drexel University

• Jamie L. Humphrey

• Ellen J. Kinnee

• Perry Sheffield, Icahn School of Medicine at Moint Sinai