Infectious Disease
Environmental Lead Exposure and Clinical Infectious Respiratory Disease in an Underrepresented, Urban Sample of Children Eva Odiko* Eva Odiko Jing Nie Heather Lehman Marina Oktapodas Feiler
Objective: To examine the association between childhood blood lead concentrations and diagnosis of streptococcal pharyngitis or croup in an underrepresented, low-income sample of children residing in Philadelphia, PA.
Methods: This retrospective cohort study included medical record data on 14,148 children ≤14 years as part of the Temple University Hospital System from 2010-2020. Lead exposure was measured via blood lead concentration (BLC) in µg/dL as reported in the medical records. Infectious upper respiratory outcomes were measured from ICD codes and included streptococcal pharyngitis (strep) or croup. Covariates included age at blood lead collection, sex, race, ethnicity, social deprivation index, and insurance type. Logistic regression and Poisson models were fit to estimate odds ratios and 95% confidence intervals for the association between BLC and strep or croup, and the frequency of strep or croup occurrence respectively. Sex-stratified models examined potential effect modification by sex on the association between BLC and our outcomes.
Results: Among participants, 28% had BLCs above the current action level of 3.5 µg/dL set by the Centers for Disease Control and Prevention (CDC). Most children with either diagnosis had a BLC between 1 – 3.4 µg/dL. Observed findings reported 174% greater odds of BLC ≥3.5 µg/dL (1.93, 3.89) and 25% greater odds of BLC between 1 – 3.4 µg/dL (0.84, 1.86) among those with strep and croup, respectively, compared to children with no diagnoses. Stratified models showed stronger associations among males for both outcomes. Higher risk of frequent strep diagnosis was also observed for those with BLC ≥3.5 µg/dL, 2.45 (1.84, 3.26).
Conclusions: Observed findings suggest evidence of an association between BLC and strep or croup and even levels below the current set action level for blood lead. This supports evidence that no level of lead exposure is safe, and CDC set lead action levels are inadequate as health indicators.