Service-based survey of dystonia in Munich

We performed a service-based epidemiological study of dystonia in Munich, Germany. Due to favourable referral and treatment patterns in the Munich area, we could provide confident data from dystonia patients seeking botulinum toxin treatment. A total of 230 patients were ascertained, of whom 188 had primary dystonia. Point prevalence ratios were estimated to be 10.1 (95% confidence interval 8.4-11.9) per 100,000 for focal and 0.3 (0.0-0.6) for generalised primary dystonia. The most common focal primary dystonias were cervical dystonia with 5.4 (4.2-6.7) and essential blepharospasm with 3.1 (2.1-4.1) per 100,000 followed by laryngeal dystonia (spasmodic dysphonia) with 1.0 (0.4-1.5) per 100,000. Copyright (C) 2002 S. Karger AG, Base

Sex-related influences on the frequency and age of onset of primary dystonia

We studied 957 cases of primary (idiopathic) dystonia and found a significant excess of female patients for segmental and focal dystonia. A novel observation was a significantly earlier age at onset in males as opposed to females for primary segmental (mean age, 44.6 versus 53.3) and focal dystonia (43.8 versus 47.8). This trend was also apparent in cervical dystonia, blepharospasm, and laryngeal dystonia. For writer's cramp and focal limb dystonia, this trend was reversed with an earlier age at onset in females. These results suggest that focal dystonia should not be treated as an homogenous group, and sex-linked factors may play a role