Timmers ER, et al. - The prevalence of psychiatric disorders, sleep problems, fatigue and health-related quality of life (HR-QoL) was investigated in a Dutch dopa-responsive dystonia (DRD) cohort. In this cohort of DRD patients, non-motor symptoms (NMS) were highly prevalent, despite adequate treatment of motor symptoms. With possible involvement of serotonergic mechanisms, the findings supported the accumulating evidence of an important non-motor phenotype in DRD. This underscored the need for systematic research into NMS symptoms and the underlying neurobiology in patients with neurometabolic disorders.

• The authors evaluated clinical characteristics, motor symptoms, type and severity of psychiatric co-morbidity, sleep problems, fatigue, and HR-QoL in DRD patients with a confirmed GCH1 mutation and matched controls.

• The authors enrolled 28 patients (18 adults and 10 children), from 10 families.
• In all patients, dystonia symptoms were well-controlled.
• Patients met the criteria significantly more often, for a lifetime psychiatric disorder according to the DSM IV compared to controls (61% vs. 29%, p < 0.05).
• Specifically, they observed higher frequencies of generalized anxiety and agoraphobia in patients (both 29% vs. 4%, p < 0.05).
• For daytime sleepiness, patients scored significantly higher than controls (ESS, 11.2 vs 5.7, p < 0.05).
• Regarding the mental component of the HR-QoL, adult patients had significantly lower scores (47 vs. 54, p < 0.05) than controls mainly associated with (worse) quality of sleep.