title: [Immune factors or depression? Fatigue correlates in Parkinson's disease].
abstract: BACKGROUND
  Fatigue is a frequent symptom in Parkinson disease (PD), but its pathogenesis remains obscure. Fatigue may be influenced by depression and motor disability, but immunological factors have been also implicated. The purpose of the study was to assess fatigue in PD patients in relation to depression and various immunological factors.
  
  
  METHODS
  Forty PD patients and 26 normal matched controls were studied. Fatigue was assessed by the Fatigue Severity Scale (FSS). The Beck Depression Inventory (BDI) was employed for depression screening. The following immunological factors were estimated: a) T- and B-lymphocytes, T-lymphocyte subsets (helper/suppressor cells) as well as natural killer cells (NK); b) circulating levels of interleukins IL-1alpha, IL-1beta, IL-6, IL-1 receptor antagonist (IL-1Ra) and tumor necrosis factor-alpha.
  
  
  RESULTS
  FSS mean score was higher in PD patients compared to controls (p < 0.01). Significant differences between patients and controls were found in the following immunological parameters. In PD patients: a) mean percentage of NK cells was higher, p < 0.01); b) IL-1beta levels were significantly increased (p < 0.01) and IL-1Ra levels were decreased (p < 0.001). FSS correlated significantly to BDI (p < 0.008). Circulating Il-1Ra levels correlated to fatigue severity (p < 0.01), but after exclusion of depressed PD subjects this correlation significance level dropped to p = 0.055.
  
  
  CONCLUSIONS
  Our results indicate that fatigue is a common non motor symptom in PD. Immunological differences between PD patients and controls were observed in percentages of NK cells, IL-1beta and IL-1Ra blood levels. Fatigue correlated to depression and IL-Ra levels. However after exclusion of depressed subjects IL-1Ra levels showed only a tendency to significance, leaving depression as the principle correlate of fatigue.
authors: Servicio de Neurología, Hospital Hippokration, Tesalónica, Grecia.
authors: Z
authors: Z
authors: Katsarou
authors: S
authors: S
authors: Bostantjopoulou
authors: O
authors: O
authors: Hatzizisi
authors: E
authors: E
authors: Giza
authors: A
authors: A
authors: Soler-Cardona
authors: G
authors: G
authors: Kyriazis
mesh_terms: D000368:Aged; D003863:Depression / Q000097:blood / Q000209:etiology* / Q000276:immunology; D005221:Fatigue / Q000097:blood / Q000209:etiology* / Q000276:immunology; D005260:Female; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein / Q000097:blood; D053582:Interleukin-1alpha / Q000097:blood; D053583:Interleukin-1beta / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D007694:Killer Cells, Natural / Q000276:immunology; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets / Q000276:immunology; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000097:blood / Q000150:complications* / Q000276:immunology / Q000523:psychology; D012720:Severity of Illness Index; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
chemical_list: C508600:IL6 protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D053582:Interleukin-1alpha; D053583:Interleukin-1beta; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha