Anorexia, fatigue, and plasma interleukin-6 levels in chronic hemodialysis patients

This study aimed at evaluating the possible relationship between anorexia and fatigue in hemodialysis (HD) patients and at measuring the plasma levels of interleukin-6 (IL-6) and C-reactive protein (CRP) in HD patients with or without anorexia and/or fatigue. The first question of the Hemodialysis Study Appetite questionnaire was used to assess the appetite of the HD patients and the vitality scale of the SF-36 to assess fatigue. The Charlson Comorbidity Index was assessed in each patient. Seventy-six HD patients were studied. Forty-four were males and 32 females. Thirty-two were classified as not-anorexic and not-fatigued, 12 as not-anorexic but fatigued, 6 as anorexic and not-fatigued, and 26 as anorexic and fatigued. Plasma IL-6 levels (pg/mL) were significantly higher in anorexic and fatigued patients (10.9 +/- 11.9) than in not-anorexic and not-fatigued (1.6 +/- 0.6) (p < 0.001) and in anorexic but not-fatigued patients (1.8 +/- 1.7) (p < 0.01). With respect to not-anorexic but fatigued patients (3.1 +/- 1.5), the difference was not statistically significant (p = 0.058). The plasma CRP levels (mg/dL) also were significantly higher in anorexic and fatigued patients (9.2 +/- 6.3) than in not-anorexic and not-fatigued patients (4.1 +/- 4.5), in anorexic but not-fatigued patients (2.5 +/- 1.6), and in not-anorexic but fatigued patients (4.1 +/- 4.4) (p = 0.001). The presence of both anorexia and fatigue in chronic HD patients is associated with significantly higher levels of plasma IL-6 and CRP and a higher frequency of comorbidities.