Hypertensive Disorders of Pregnancy May Be Associated With Increased Autism and ADHD Risk

Infants exposed to hypertensive disorders in utero may be at increased risk for autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD), according to research published in JAMA Psychiatry.

Researchers from the United Kingdom and southwest Ireland independently reviewed data from cohort, cross-sectional, and case-control studies to identify associations between exposure to hypertensive disorders of pregnancy (HDP) and the risk for neurodevelopmental disorders, particularly ASD and ADHD.

A total of 61 unique studies were identified, of which 11 had adjusted estimates for ASD and 6 had adjusted estimates for ADHD. The pooled odds ratio (OR) for ASD among individuals exposed to HDP was 1.35 (95% CI, 1.11-1.64). Comparatively, the OR for ADHD among HDP-exposed offspring was 1.29 (95% CI, 1.22-1.36).

Subgroup analysis of the association between preeclampsia and ASD revealed an OR of 1.50 (95% CI, 1.26-1.78), and the association between other HDP and ASD revealed an OR of 1.25 (95% CI, 0.90-1.73); these were not found to be statistically significant (P =.33). Additionally, no statistically significant difference was seen between preeclampsia and ADHD (OR 1.28; 95% CI, 1.22-1.36) or other HDP and ADHD (OR 1.70; 95% CI, 1.06-2.72) (P =.24).

According to subgroup and sensitivity analyses, 11 studies found significant associations between HDP and ASD, including 6 studies from North America (OR 1.39; 95% CI, 1.09-1.77), 4 studies from Europe (OR 1.53; 95% CI, 1.26-1.87), and 1 study from Australia (OR 0.64; 95% CI, 0.43-0.95) (P <.001).

In addition, there was a close trend toward significance in 3 case-control studies (pooled OR 1.34; 95% CI 1.25-1.43) and 3 cohort studies (pooled OR 1.21; 95% CI, 1.10-1.32) (P = .08), all of which demonstrated an association between HDP and ADHD. Few patterns were observed among included studies, with researchers finding largely inconsistent associations in individual estimates.

The inclusion of only English-language studies and the lack of appropriate or extensive search criteria during the literature review represent 2 limitations of this study. Additionally, the investigators note that some of the studies included in the meta-analysis did not account for potential confounders.

If the association between HDP and ASD and ADHD are causal, the findings from this study “highlight the potential need for increased developmental screening of HDP-exposed infants to allow early intervention, which may improve neurodevelopmental outcome.”

Reference

Maher GM, O’Keeffe GW, Kearney PM, et al. Association of hypertensive disorders of pregnancy with risk of neurodevelopmental disorders in offspring: a systematic review and meta-analysis [published online June 6, 2018]. JAMA Psychiatry. doi: 10.1001/jamapsychiatry.2018.0854