Selective Serotonin Reuptake Inhibitors (SSRIs) and Serotonin Norepinephrine Reuptake Inhibitors (SNRIs) During Pregnancy and the Risk for Autism spectrum disorder (ASD) and Attention deficit hyperactivity disorder (ADHD) in the Offspring: a True Effect or a Bias? A Systematic Review & Meta-Analysis

Background and objective: An inconsistent association between exposure to SSRIs and SNRIs and the risk for ASD and ADHD in the Offspring was observed in observational studies. Some suggest that the reported association might be due to unmeasured confounding. We aimed to study this association and to look for sources of bias by performing a systematic review and meta-analysis. Methods: Medline, Embase, and the Cochrane Library were searched up to June 2019 for studies reporting on ASD and ADHD in the Offspring following exposure during pregnancy. We followed the PRISMA 2009 guidelines for data selection and extraction. Outcomes were pooled using random-effects models and odds ratios (OR), and 95% confidence intervals (CI) were calculated for each outcome using the adjusted point estimate of each study. Results: Eighteen studies were included in the meta-analysis. We found an association between SSRIs/SNRIs prenatal use and the risk for ASD and ADHD (OR=1.42, 95% CI: 1.23-1.65, I-2=58%; OR=1.26, 95% CI: 1.07-1.49, I-2=48%, respectively). Similar findings were obtained in women who were exposed to SSRIs/SNRIs before pregnancy, representing statistically significant association with ASD (OR=1.39, 95% CI: 1.24-1.56, I-2=33%) and ADHD (OR=1.63, 95% CI: 1.50-1.78, I-2=0%) in the Offspring, although they were not exposed to those medications in utero. Conclusions: Although we found an association between exposure to SSRIs/SNRIs during pregnancy and the risk for ASD and ADHD, an association with those disorders was also present for exposure pre-pregnancy, suggesting that the association might be due to unmeasured confounding. We are aiming to further assess the role of potential unmeasured confounding in the estimation of the association and perform a network meta-analysis.