Sex-linked dystonia parkinsonism (XDP, DYT3, "Lubag") is an adult-onset, progressive, debilitating movement disorder first described in Filipino males from Panay Island in 1975. XDP manifests predominantly as torsion dystonia, later combined with or sometimes replaced with parkinsonism. Within the Island of Panay, the preva-lence rate is highest in the province of Capiz, where 1:4000 men suffer from the disorder. There is a high degree of penetrance and generalization. While women often serve as carriers, XDP is not limited to men. An updated XDP Philippine registry (as of January 2010) has identified 505 cases, with 500 males and 5 females. While some report that females may carry a milder form of the disorder, in our experience, both sexes generally follow a similar progressive clinical course.

Human ; Male ; Female ; Aged ; Adult ; Dystonia ; Dystonia Musculorum Deformans ; Dystonic Disorders ; Genetic Diseases, X-linked ; Islands ; Parkinsonian Disorders ; Penetrance

OBJECTIVE: X-linked dystonia parkinsonism (XDP) is an adult-onset, progressive and debilitating movement disorder described among Filipino males from Panay Island. The available oral medications have been ineffective. While chemodenervation with botulinum toxin A works and deep brain stimulation surgery is promising, these are not affordable for the vast majority of patients. Thus, we decided to look into the efficacy, safety and tolerability of levodopa+carbidopa (levodopa) versus placebo among patients with XDP.

METHODS: This was a double blind, randomized, placebo-controlled clinical trial. Patients were randomized to receive levodopa or placebo for 6 months. The dose was increased gradually until 1000 mg levodopa/day is reached or until side effects appear.

RESULTS: A total of 86 out of 94 randomized patients (91.5%) were included in the intention-to-treat cohort for the primary efficacy analysis. Nineteen patients (9 in levodopa, 10 in placebo) dropped out or were lost to follow up. There was no significant difference in the baseline and last visit Burke Fahn Marsden Dystonia Rating Scale and the part III of the Unified Parkinson's Disease Rating Scale scores between levodopa and placebo. The most common adverse events in the levodopa group were increased movements, pain and nausea/ vomiting.

CONCLUSION: While levodopa is safe and well-tolerated, it does not have any effect in alleviating the dystonia or parkinsonism in XDP.

Human ; Dystonia ; Parkinsonian Disorders ; Levodopa ; Carbidopa ; Parkinson Disease