Overlooked hematological markers of disease activity in rheumatoid arthritis.

Aim: The aim of this study was to investigate the relationship between hematological markers and disease activity in patients with rheumatoid arthritis (RA).
Method: The study was designed and performed in the Department of Rheumatology of the Sakarya University Faculty of Medicine. In total, 102 patients with RA were retrospectively enrolled. We used the Disease Activity Score of 28 joints (DAS28) instrument to evaluate disease activity. Laboratory assessments included complete blood cell counts, measurement of erythrocyte sedimentation rate (ESR) and assessment of C-reactive protein (CRP) level. Exclusion criteria included active infection and/or the presence of any hematological, cardiovascular or metabolic disorder.
Results: We found that the neutrophil lymphocyte ratio (NLR) and mean platelet volume (MPV) varied by disease activity status. NLR values correlated positively with the DAS28 scores of RA patients. Especially, higher NLR values (3.92 ± 0.31) were evident in the group exhibiting high-level disease activity, whereas the MPV values were lowest (7.11 ± 0.91 fL) in this group. Additionally, no significant difference was evident between DAS28 scores and platelet distribution width (PDW) values in patients with RA (r = -0.055, P = 0.124).
Conclusions: We found that the MPV value may serve as a marker of the absence of acute-phase disease, and the NLR level as a marker of the presence of such disease, in patients with RA. More detailed analysis of disease activity is required to further explain the associations of the markers described above with disease activity.
(© 2015 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.)