title: Overlooked hematological markers of disease activity in rheumatoid arthritis.
abstract: OBJECTIVE
  The aim of this study was to investigate the relationship between hematological markers and disease activity in patients with rheumatoid arthritis (RA).
  
  
  METHODS
  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.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Division of Rheumatology, Faculty of Medicine, Sakarya University, Sakarya, Turkey.
authors.forename: İbrahim
authors.initials: İ
authors.lastname: Tekeoğlu
authors.affiliation: Department of Medical Physiology, Faculty of Medicine, Sakarya University, Sakarya, Turkey.
authors.forename: Gönül
authors.initials: G
authors.lastname: Gürol
authors.affiliation: Department of Physical Medicine and Rehabilitation, Division of Rheumatology, Faculty of Medicine, Sakarya University, Sakarya, Turkey.
authors.forename: Halil
authors.initials: H
authors.lastname: Harman
authors.affiliation: Department of Microbiology, Sakarya University Education and Research Hospital, Sakarya, Turkey.
authors.forename: Engin
authors.initials: E
authors.lastname: Karakeçe
authors.affiliation: Department of Microbiology, Faculty of Medicine, Sakarya University, Sakarya, Turkey.
authors.forename: İhsan Hakkı
authors.initials: İH
authors.lastname: Çiftçi
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood; D001792:Blood Platelets; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000032:analysis; D005260:Female; D006801:Humans; D018655:Lymphocyte Count; D008214:Lymphocytes; D008297:Male; D063847:Mean Platelet Volume; D008875:Middle Aged; D009504:Neutrophils; D010976:Platelet Count; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D012720:Severity of Illness Index; D014421:Turkey
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein
keywords: inflammation; mean platelet volume; neutrophil/lymphocyte ratio; rheumatoid arthritis