It is unclear whether our findings are specific to OCD or common among multiple psychiatric disorders. Other studies have provided circumstantial evidence for an association between immune-related disorders—including atopic disease and autoimmunity—and psychiatric comorbidities, including depression, schizophrenia, autism spectrum disorder, and other developmental disorders (Sweeten et al. 2003; Croen et al. 2005; Mouridsen et al. 2007; Gesundheit et al. 2013; Postal and Appenzeller 2015; Schans et al. 2017). Recent data suggest a link between stress-related disorders and subsequent autoimmune disease (Song et al. 2018). Moreover, other medical comorbidities, including migraines and respiratory diseases, are known to be more common among adults with OCD (Witthauer et al. 2014). Implementation of standardized medical comorbidity questionnaires across multiple pediatric psychiatric clinics may aid in determining whether particular comorbidities are associated with increased risk of specific psychiatric symptoms or diagnoses.
