Disease aggressiveness indices association with fatigue in rheumatoid arthritis patients

In RA patients with aggressive clinical course and concomitant inflammation of many joints, rapidly progressive erosive joint lesions with the development of deformities often develop fatigue. Elevated levels of antibodies to anti-cyclic citrullinated peptide antibodies (anti-CCP) and rheumatoid factor (RF) indicate laboratory aggressiveness. The aim of the study was to determine which laboratory aggressiveness parameter is associated with the development of fatigue in RA patients. Overall 30 RA patients were included in the study: 23 females (76.7%) and 7 males (23.3%) with the average age 59.5±11.2 (ranging from 39 to 79), who were subjected to semi-structured questionnaire. To achieve the goal, patients were interviewed and indicators of disease aggressiveness: RF, anti-CCP, immunoglobulins IgA RF, IgM RF, IgG RF and anti-carbamylated proteins antibodies (anti-CarP) were measured using ELISAs according to the manufacturer’s protocols. A positive correlation was found between RF and RF IgM, IgG, respectively; between RF IgA and RF IgM, IgG and anti-CarP, respectively, in the fatigue group of RA patients. A positive correlation was found between RF and RF IgM; as well as between RF IgG and anti-CarP, anti-CCP, respectively, in the group of RA patients without fatigue. In both groups of RA patients, a positive correlation was found between RF IgM and RF IgG, anti-CarP, respectively. Of the laboratory parameters of aggression, RF IgA is more closely associated with fatigue in RA patients.