AIMS/HYPOTHESIS: The aim of this study was to investigate psychiatric morbidity following childhood onset of type 1 diabetes.

METHODS: In a matched, population-based cohort study based on Danish national registers, we identified children and adolescents who had been diagnosed as an in- or outpatient with type 1 diabetes before the age of 18, and afterwards diagnosed with a psychiatric disorder (n = 5084). Control individuals were matched according to sex and date of birth (n = 35,588). The Cox proportional hazards model was used to assess associations between type 1 diabetes and the incidence of psychiatric disorders as well as the effects of age at onset and duration of type 1 diabetes on the risk of subsequently developing psychiatric morbidities.

RESULTS: An increased risk of being diagnosed with mood disorders and anxiety, dissociative, eating, stress-related and somatoform disorders was observed in both sexes in the years following type 1 diabetes onset, with the highest risk observed five years or more after onset (HR 1.55 [95% CI 1.38, 1.74]). The risk of psychoactive substance-misuse disorders increased significantly only in boys, and the risk of personality disorders increased only in girls.

CONCLUSIONS/INTERPRETATION: In the years following type 1 diabetes onset, an increased risk of eating disorders, anxiety and mood disorders, substance misuse, and personality disorders was found. These findings highlight a clinical need to monitor the mental health of children and adolescents in the years following type 1 diabetes onset to identify and treat psychiatric problems associated with type 1 diabetes.