The clinical features of psychogenic movement disorders resembling tics

Abstract

Background Psychogenic movement disorders (PMDs) may be difficult to differentiate from organic abnormal movements. Methods We aimed to characterise the prevalence and clinical features of PMDs resembling tics during the last 3.5 years in our centre. Results We studied 9 patients (five females) with psychogenic tics representing 4.9% of all 184 patients first evaluated for a PMD during the study period. The mean age at onset was 34.1 years. Lack of premonitory sensations, absence childhood and family history of tics, inability to suppress the movements and coexistence with other PMDs and pseudoseizures were common in our patients. Compared with 273 patients with Tourette syndrome, those with PMDs resembling tics were older: 36.3 versus 18.7 years ( p=0.014) at presentation and more frequently female ( p=0.030). Conclusions Movements resembling tics are observed in a small proportion of patients with PMDs. Clinical features can help to differentiate them from organic tics.