Association of Strabismus With Mood Disorders, Schizophrenia, and Anxiety Disorders Among Children

IMPORTANCE: Children with strabismus have poorer functional vision and decreased quality of life than those without strabismus. OBJECTIVE: To evaluate the association between strabismus and mental illness among children. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study analyzed claims data from the OptumLabs Data Warehouse, a longitudinal deidentified commercial insurance claims database, from 12 005 189 patients enrolled in the health plan between January 1, 2007, and December 31, 2017. Eligibility criteria included age younger than 19 years at the time of strabismus diagnosis, enrollment in the health plan between 2007 and 2018, and having at least 1 strabismus claim based on International Classification of Diseases, Ninth Revision, Clinical Modification and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Clinical Modification codes. Controls were children in the same database with no eye disease codes other than refractive error reported. Demographic characteristics and mental illness claims were compared. Statistical analysis was conducted from December 1, 2018, to July 31, 2021. MAIN OUTCOMES AND MEASURES: Presence of mental illness claims. RESULTS: Among the 12 005 189 patients (6 095 523 boys [50.8%]; mean [SD] age, 8.0 [5.9] years) in the study, adjusted odds ratios for the association of mental illnesses with strabismus were 2.01 (95% CI, 1.99-2.04) for anxiety disorder, 1.83 (95% CI, 1.76-1.90) for schizophrenia, 1.64 (95% CI, 1.59-1.70) for bipolar disorder, 1.61 (95% CI, 1.59-1.63) for depressive disorder, and 0.99 (95% CI, 0.97-1.02) for substance use disorder. There was a moderate association between each strabismus type (esotropia, exotropia, and hypertropia) and anxiety disorder, schizophrenia, bipolar disorder, and depressive disorder; odds ratios ranged from 1.23 (95% CI, 1.17-1.29) for the association between esotropia and bipolar disorder to 2.70 (95% CI, 2.66-2.74) for the association between exotropia and anxiety disorder. CONCLUSIONS AND RELEVANCE: This cross-sectional study suggests that there was a moderate association between strabismus and anxiety disorder, schizophrenia, bipolar disorder, and depressive disorder but not substance use disorder. Recognizing that these associations exist should encourage mental illness screening and treatment for patients with strabismus.