Head trauma in primary cranial dystonias: a multicentre case-control study.

Abstract

The relationship between prior trauma and primary adult-onset dystonia is not well understood. Previous uncontrolled observations and exploratory case-control studies have yielded contradictory results. To analyse the association between cranial dystonia and prior head trauma. An ad hoc multicentre case-control study was performed using a semistructured interview to collect detailed information on the history of head trauma before disease onset in five Italian tertiary referral centres for movement disorders. The presence of a history of head trauma and of post-traumatic sequelae (loss of consciousness, bone fractures, scalp/facial wounds) before disease onset was recorded from 177 patients with primary adult-onset cranial dystonia and from 217 controls with primary hemifacial spasm matched by age strata and sex. Differences between groups were assessed by Mann-Whitney U test and Fisher's exact test, and the relationship between prior head trauma and case/control status was analysed by multivariate logistic regression models. No association was found between vault/maxillofacial trauma and cranial dystonia. Most reported traumas occurred several years before disease onset. None of the main post-traumatic sequelae altered the chance of developing cranial dystonia compared with patients with primary hemifacial spasm, nor did head trauma modify the age at onset of cranial dystonia. These results do not support prior head trauma as a possible environmental factor modifying the risk of developing late-onset cranial dystonia. The lack of association may have pathogenetic and medical-forensic implications.