Neurological and psychiatric characterization of rapid-onset dystonia-parkinsonism over time

Introduction: The onset of symptoms in Rapid-onset dystonia-parkinsonism (RDP) is typically over days to weeks and is often triggered by stressors like fever or childbirth. Limited information is available on how the motor and nonmotor symptoms evolve over the course of the disease. Our longitudinal study analyzed data from a cohort of RDP patients, documenting their symptoms across multiple visits. Methods: We characterized the phenotypic evolution of 14 individuals positive for ATP1A3 mutations (7 females, 7 males; mean examination age = 37 years, mean age of onset = 20 years). We focused on neurologic, cognitive, and neuropsychological data collected during in-person visits (mean interval between testing = 51/2 years). Results: Initially, all participants exhibited bulbar symptoms. Headaches were noted in 50 %, seizures in 31 %, and tremors in 36 %. At follow-up, 29 % of those initially without headaches developed them, 22 % without prior seizures experienced them, and 56 % previously without tremors developed them. No improvements were seen in those with headaches; however, seizures and tremors improved in 25 % and 80 % of cases, respectively. For Burke-Fahn-Marsden Dystonia Rating Scale, Unified Parkinson's Disease Rating Scale, and International Cooperative Ataxia Rating Scale scores, improvement consisted of the reduction of the symptom. Cognitive functions improved from mildly impaired to low-average, and psychiatric evaluations indicated mild anxiety levels, slight increases in obsessive-compulsive behaviors, and decreased depression scores over time. Conclusions: This longitudinal analysis highlights the complex evolution of RDP, demonstrating significant variability in motor function and other symptoms such as headaches, seizures, and tremors.