Autism and gestational exposures to nonsteroidal anti-inflammatory drugs (NSAIDs) and acetaminophen

Nonsteroidal anti-inflammatory drugs (NSAIDs) and acetaminophen are commonly used during pregnancy to reduce pain and fever. Both drugs cross the placenta and the blood-brain barrier. NSAIDs can inhibit cyclooxygenase, whereas acetaminophen is primarily as an analgesic/antipyretic and COX-2 inhibitor. Growing evidence links prenatal inflammation to autism and autism-spectrum (ASD) diagnosis. Northern California families were enrolled from 2003-2010 in the CHARGE (Childhood Autism Risks for Genetics and Environment) population-based case-control study. Children aged 24-60 months were evaluated to have autism (n=357), ASD, (n=163), or typically development (TD,n=371) at the University of California-Davis Medical Investigations of Neurodevelopmental Disorders Institute using standardized clinical assessments. We used published criteria to define autism and ASD (e.g., ASD was defined as meeting criteria for autism on ADOS, and on one of the communication or social domains of the ADI-R, and scoring within 2 points of meeting the other cut-off). In preliminary analysis, we calculated unadjusted odds ratios (OR) for the association between autism and gestational exposure to NSAIDs. Mothers of children with autism or ASD were less likely than those of TD children to report having taken NSAIDs during periconception and pregnancy (OR=0.67, 95%CI0.51-0.88). Forty percent of mothers reported taking NSAIDs and acetaminophen. In further analyses we will examine confounders and the effects of drugs both separately and combined. Our preliminary results suggest a protective relationship between gestational exposure to NSAIDs and autism. Given that the exposure is common and the relevant biologic pathways are complex, these relationships deserve further elucidation.