Hematologic parameters and disease activity in patients with primary Sjögren's syndrome

Aim of the workTo evaluate hematologic parameters in patients with primary Sjögren's syndrome (PSS) and their association with disease activity.Patients and methodsSixty-five PSS patients and 65 age and sex matched control were studied. Neutrophil to lymphocyte ratio (NLR), mean platelet volume (MPV), red blood cells distribution width (RDW), platelet to lymphocyte ratio (PLR) and platelet count were evaluated. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured. The European league against rheumatism (EULAR) Sjögren's syndrome disease activity index (ESSDAI) was assessed.ResultsThe mean age of patients was 47.8 ± 12.1 years and disease duration 5.71 ± 1.2 years and they were 63 females and 2 males. The mean ESSDAI was 6.4 ± 7.9 (3–25). 11 had neurological involvement. 92.3% of patients received low-dose prednisolone (<10 mg/day) and hydroxychloroquine (HCQ). The mean NLR (1.83 ± 0.8), PLR (131.9 ± 32.5) and MPV (8.82 ± 1.4) in patients was significantly higher than in control (NLR 1.57 ± 0.56, PLR 109.9 ± 24.7 and MPV 7.71 ± 1.3; p = 0.036, p < 0.001 and p < 0.001 respectively). The RDW tended to be higher in patients (13 ± 1.56) compared to control (12.83 ± 1.13) (p = 0.46). There was a significant correlation between ESSDAI with NLR (r = 0.29, p = 0.02), RDW (r = 0.37, p = 0.002), ESR (r = 0.32, p = 0.01) and CRP (r = 0.33, p = 0.007) and between MPV with CRP (r = 0.27, p = 0.03) and between RDW and ESR (r = 0.36, p = 0.003).On regression analysis, NLR and RDW were significant predictors of disease activity (p = 0.01 and p = 0.02 respectively).ConclusionThe MPV, PLR and NLR, were significantly increased in PSS. NLR and RDW can be used as indicators of disease activity.