Prenatal cannabis use and the risk of attention deficit hyperactivity disorder and autism spectrum disorder in offspring: A systematic review and meta-analysis

Abstract

Background: It is plausible that exposure to cannabis in-utero could be associated with an increased risk of neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD) symptoms and autism spectrum disorder (ASD) during childhood and adolescence; however, mixed results have been reported. This study investigated whether there is an association between prenatal cannabis use and ADHD symptoms and ASD in offspring using a systematic review and meta-analysis methodology.

Methods: A systematic literature search was conducted in PubMed/Medline, Scopus, EMBASE, Web of Science, Psych-Info, and Google Scholar to identify relevant studies. The study protocol has been preregistered in the Prospective Register of Systematic Reviews (PROSPERO) (CRD42022345001), and the Newcastle-Ottawa Quality Assessment Scale (NOS) was used to assess the methodological quality of included studies. An inverse variance weighted random effect meta-analysis was conducted to pool the overall effect estimates from the included studies.

Results: Fourteen primary studies, consisting of ten on ADHD and four on ASD, with a total of 203,783 participants, were included in this study. Our meta-analysis underscores an increased risk of ADHD symptoms and/or disorder [β = 0.39: 95 % CI (0.20-0.58), I² = 66.85 %, P = 0.001)] and ASD [RR = 1.30: 95 % CI (1.03-1.64), I² = 45.5 %, P = 0.14] associated with in-utero cannabis exposure in offspring compared to their non-exposed counterparts. Additionally, our stratified analysis highlighted an elevated risk of ADHD symptoms [β = 0.54: 95 % CI (0.26-0.82)] and a marginally significant increase in the risk of diagnostic ADHD among exposed offspring compared to non-exposed counterparts [RR = 1.13, 95 % CI (1.01, 1.26)].

Conclusion: This study indicated that maternal prenatal cannabis exposure is associated with a higher risk of ADHD symptoms and ASD in offspring.

Keywords: ADHD; ASD; Cannabis; Marijuana; Neurodevelopmental disorders; Offspring; Pregnancy; Prenatal.