Evaluation of fatigue in Parkinson's disease using the Brazilian version of Parkinson's Fatigue Scale.

OBJECTIVE: Fatigue is common in Parkinson's disease (PD). However, factors associated with fatigue in PD are still controversial. This study aimed to translate the Parkinson's Fatigue Scale (PFS) into Brazilian-Portuguese, to test its psychometric properties, and to assess the severity of fatigue in PD as well as its relation to demographic and clinical features, depression, anxiety, excessive daytime sleepiness and cognitive performance. METHODS: We translated and assessed the internal consistency of the Brazilian version of the PFS. After, we assessed 87 PD patients with several neurological and psychopathological instruments. RESULTS: The Brazilian version of PFS had good internal consistency (Cronbach's alpha = 0.939). Clinical significant fatigue was present in 36 patients (41.4%). A logistic regression analysis showed that fatigue was better explained by dysthymia (P = 0.006), more severe symptoms of depression as assessed by the Hamilton Depression Rating Scale (P = 0.027), daytime sleepiness (P = 0.022) and female gender (P = 0.031). CONCLUSIONS: Fatigue is a common non-motor symptom in PD and seems to be associated with female gender, dysthymia, severity of depression and daily somnolence.