[Inflammatory mechanisms of fatigue syndrome in Parkinson's disease]

To study clinical characteristics of fatigue syndrome in patients with Parkinson's disease (PD) and a role of inflammation in its development.

We examined 98 patients with confirmed diagnosis of PD and 18 healthy people. Clinical examination included an analysis of anamnesis and objective somatic symptoms. The unified Parkinson's disease rating scale, The Hoehn and Yahr scale, the Multidimensional Fatigue Inventory (MFI-20) scale, the Modified Fatigue Impact Scale (MFIS), the Hospital Anxiety and Depression Scale (HADS), The Epworth Sleepiness Scale (ESS), Vein's Autonomic Symptoms Questionnaire (VASQ) were used for quantitative assessment. Serum concentrations of IL-6 were measured in 65 patients and 18 controls using ELISA.

In PD patients, fatigue assessed with MFI-20 was recorded in 46 (47%) cases and fatigue as assessed with MFIS in 45 (46%) of cases. High frequency and severity of fatigue syndrome were observed. The most prominent components in the structure of fatigue were physical fatigue, reduced motivation and decreased activity. Signs of fatigue increased with disease progression. Correlation between fatigue and axial motor symptoms of PD is of interest. Patients had higher serum IL-6 levels compared to the controls. Concentrations of IL-6 were correlated with fatigue severity and its main components (general and physical fatigue, decreased activity) and with depression level.