Fatigue in Japanese Patients with Parkinson's Disease: A Study Using Parkinson Fatigue Scale

The objective of this multicenter cross-sectional study was to determine the prevalence of fatigue and factors contributing to it in a large sample of Japanese patients with Parkinson's disease (PD). We used the 16-item Parkinson Fatigue Scale (PFS-16), which was designed to assess fatigue exclusively associated with PD. We carried out this study using PFS-16, the Unified Parkinson's Disease Rating Scale, Zung's Self-Rating Depression Scale, Parkinson's Disease Sleep Scale (PDSS), and the PD quality of life (QOL) scale (PDQ-39) by interview using questionnaires and physical examination by neurologists in 361 nondemented PD patients. Fatigue (an average PFS score of 3.3 or greater) was revealed in 151 patients (41.8%). Multiple logistic regression analysis indicated that the significant independent variables related to the presence of fatigue were the scores of PDSS and PDQ-39. Depression score was not a significant contributing factor. Our study revealed that the prevalence of fatigue in Japanese PD patients is as high as that in Western countries, and that fatigue is a relatively independent symptom, although sleep disturbance may be associated with fatigue. Since fatigue is significantly related to QOL reduction, therapeutic interventions including treatment of sleep disturbance are important. (C) 2009 Movement Disorder Society