Association between Autism Spectrum Disorder and Food Allergy: A Systematic Review and Meta‐analysis

Autism spectrum disorder (ASD) and food allergy (FA) are global public health problems. Several studies have explored the association between ASD and FA, but the conclusions were inconsistent. The aim of this review was to evaluate the relationship between ASD and FA. The PubMed, Embase, and Web of Science databases were searched from inception to February 2, 2020. Studies investigating the association between ASD and FA were included. A random effects model was used to pool risk estimates. Subgroup analysis and sensitivity analysis were used to explore the potential sources of heterogeneity. Fifteen studies with a total of 293,130 participants were included in this review. The pooled prevalence of FA in individuals with ASD was 13% (95% confidence interval (CI): 0.10–0.17), while the pooled prevalence of FA in controls was 5% (95% CI: 0.04–0.07). The pooled odds ratio (OR) for FA in individuals with ASD was 2.45 (95% CI: 2.25–2.67). One study examined the prevalence of ASD in participants with FA. The prevalence of ASD in individuals with FA was 3.5% (95% CI: 0.029–0.042), while the prevalence of ASD in the control group was 1.6% (95% CI: 0.015–0.017). Five study examined the OR of ASD in participants with FA. The OR for ASD in individuals with FA was 1.95 (95% CI: 1.73–2.19). The results of this systematic review and meta‐analysis seem to reveal a significant association between ASD and FA. Lay Summary This systematic review and meta‐analysis evaluate the relationship between ASD and FA. We found that the prevalence of FA was higher in participants with ASD than in controls and participants with ASD were at risk of developing FA and the prevalence of ASD was higher in participants with FA than in controls and participants with FA were at risk of developing ASD. Additional research such as a prospective cohort study is required to better understand the relationship between ASD and FA.