Psychiatric comorbidity is common in dystonia and other movement disorders.

Objective: To determine rates of psychiatric comorbidity in a clinical sample of childhood movement disorders (MDs).

Design: Cohort study.

Setting: Tertiary children's hospital MD clinics in Sydney, Australia and London, UK.

Patients: Cases were children with tic MDs (n=158) and non-tic MDs (n=102), including 66 children with dystonia. Comparison was made with emergency department controls (n=100), neurology controls with peripheral neuropathy or epilepsy (n=37), and community controls (n=10 438).

Interventions: On-line development and well-being assessment which was additionally clinically rated by experienced child psychiatrists.

Main Outcome Measures: Diagnostic schedule and manual of mental disorders-5 criteria for psychiatric diagnoses.

Results: Psychiatric comorbidity in the non-tic MD cohort (39.2%) was comparable to the tic cohort (41.8%) (not significant). Psychiatric comorbidity in the non-tic MD cohort was greater than the emergency control group (18%, p<0.0001) and the community cohort (9.5%, p<0.00001), but not the neurology controls (29.7%, p=0.31). Almost half of the patients within the tic cohort with psychiatric comorbidity were receiving medical psychiatric treatment (45.5%) or psychology interventions (43.9%), compared with only 22.5% and 15.0%, respectively, of the non-tic MD cohort with psychiatric comorbidity.

Conclusions: Psychiatric comorbidity is common in non-tic MDs such as dystonia. These psychiatric comorbidities appear to be under-recognised and undertreated.