Maternal paracetamol use may raise ADHD risk in kids by age 10: Study

New Delhi : Children, especially females, born to women who took acetaminophen (paracetamol) during pregnancy may be at a higher risk of developing childhood attention deficit hyperactivity disorder (ADHD) by the time they age 10, claimed a study.

The study, published in the journal Nature Mental Health, showed that children whose mothers had biomarkers of acetaminophen present in their plasma had a 3.15 times higher likelihood of an ADHD diagnosis.

The findings showed that the link was stronger among females than males. Girls of APAP-exposed mothers showed a 6.16 times higher likelihood of ADHD. However, the association was found to be weaker and nonsignificant in males.

Paracetamol is widely used during pregnancy, accounting for an estimated 70 per cent of pregnant individuals in the US, Europe, and Asia.

Even though paracetamol has been classified as a low-risk medication by regulatory agencies such as the US Food and Drug Administration and the European Medicines Agency, evidence is mounting to suggest that it can potentially increase the risk of adverse neurodevelopmental outcomes, including ADHD and autism spectrum disorder.

For the new study, researchers from the University of Washington, US, analysed plasma biomarkers of acetaminophen (APAP) exposure in a cohort of 307 African American mother-child pairs.

Detection of APAP in second-trimester maternal blood samples correlated with increased odds of ADHD diagnosis in children by age 8-10, they said in the paper. In the study, APAP metabolites were detected in 20.2 per cent of maternal plasma samples.

Placental gene expression analysis of a subset of 174 participants indicated sex-specific transcriptional changes. In females, APAP exposure was associated with upregulation of immune-related pathways, including increased expression of immunoglobulin heavy constant gamma 1 (IGHG1).

Increased IGHG1 expression was statistically linked to ADHD diagnoses, with mediation analysis suggesting that APAP's effect on ADHD was partly mediated through this gene's placental expression, the researchers said.

The findings align with prior epidemiological studies and experimental animal research linking prenatal APAP exposure to neurodevelopmental disruptions.

The current study eliminated the bias concerns raised in previous studies where APAP use was self-reported by using objective biomarker measurements, they said, while calling for further studies.