ADHD News & Research

Meta-Analysis: High Blood Pressure During Pregnancy Linked with Increased Risk of ADHD and Autism

A systematic review of 61 studies found that hypertensive disorders of pregnancy (HDP) are associated with a small increase in likelihood that the child will have an autism spectrum disorder or ADHD.

June 21, 2018

There are a number of complications during pregnancy are thought to increase risk of ADHD in offspring: high glycyrrhizin intake, exposure to certain toxins and pollutants, and now – according to a recent study1 – hypertensive disorders of pregnancy (HDP).

A group of researchers in Ireland and the United Kingdom completed meta-analyses of pooled odds ratios (ORS) cited in 61 studies that examined the connection between HDP and risk of neurodevelopmental disorders including autism spectrum disorder (ASD) and ADHD.

20 of the included studies had estimates for ASD, of which 11 (comprising 777,518 total participants) gave adjusted estimates. The pooled adjusted OR was 1.35.

Ten of the included studies had estimates for ADHD, of which six (comprising 1,395,605 total participants) gave adjusted estimates. The pooled adjusted OR was 1.29.

The remaining 31 studies contained estimates for other neurodevelopmental disorders, but no significant association was found.

“Our main findings suggest that hypertensive disorders in pregnancy are associated with about 30% increase in the likelihood of autism spectrum disorders (ASD) and ADHD in the offspring, compared to offspring not exposed to hypertensive disorders in pregnancy,” says study author Ali Khashan.

However, he noted, “The study results should be interpreted with caution because even with this apparent increase, the absolute risk remains small.” There were limitations in the literature, including sample size and use of validated measures, which prevent the analyses from determining causality.

The research, published online in JAMA Psychiatry, calls for increased pediatric screenings for ASD and ADHD in infants exposed to HDP to allow for early intervention treatments to improve childhood functioning.

1Maher, Gillian M., et al. “Association of Hypertensive Disorders of Pregnancy With Risk of Neurodevelopmental Disorders in Offspring.” JAMA Psychiatry online, 16 June 2018. doi:10.1001/jamapsychiatry.2018.0854