Association between early-life mosquito repellents exposure and ADHD-like behaviours

Abstract Background Limited research has explored the impact of mosquito repellents exposure during early life on ADHD symptoms. This study aimed to explore the associations of exposure to mosquito repellents from pregnancy to 3 years old and the prevalence of ADHD-like behaviours among children aged 3–9 years, and further identify the sensitive exposure period. Methods A cross-sectional study was conducted, including 12 275 children in Hefei City, China. Exposure was self-reported via primary caregivers. ADHD-like behaviours were measured by the Swanson, Nolan and Pelham, version IV scale (SNAP-IV), and Conners’ Parent Rating Scale (CPRS). Cross-over analysis, binary logistic regression and linear regression were employed. Results After adjusting for confounding variables, early-life exposure to mosquito repellents was associated with a higher risk of ADHD-like behaviours (OR = 1.81, 95% CI = 1.49–2.19). By comparing the strength of the association for each subgroup, we found exposure during 1–3 years old was a sensitive period (OR = 1.89, 95% CI = 1.25–2.87) by the cross-over analysis. Furthermore, we found a dose–response relationship in which the likelihood of ADHD-like behaviours increased with children’s early-life mosquito repellents exposure dose. Conclusions Early-life exposure to mosquito repellents is linked with an elevated risk of ADHD-like behaviours in children, with a sensitive period identified during 1–3 years old.