Exploring the Association between Blood Indices and Skin and Joint Activity of Psoriatic Arthritis

The exact cause of psoriatic arthritis is still unknown, but hypotheses suggest the role of hematological parameters in the onset and severity of the disease. This study evaluated the hematological indices and their association with skin and joint activity in psoriatic arthritis. This cross-sectional study included 74 patients with psoriatic arthritis. Demographical and clinical data, blood indices, psoriasis area and severity index (PASI) score and disease activity in psoriatic arthritis (DAPSA) scores were calculated for all patients. The mean age of the patients was 48.89±12.03 years and most were female (n=49). A significant correlation was observed between age and number of underlying diseases with PASI and DAPSA scores. Mean PASI and DAPSA scores were 5.19 and 15.13, respectively. The severity of psoriasis was mild in 58.1%, moderate in 36.5%, and severe in 4.5% of the cases. The activity of psoriatic arthritis was improved in 2.1%, low in 55.4%, moderate in 24.3%, and high in 1.8% of the patients. A significant association was found between erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), red cell distribution width (RDW), neutrophil-to-lymphocyte ratio (NLR), platelet (PLT) count, mean platelet volume (MPV), and PASI scores, while no statistically significant association was reported for PLR. A significant correlation was observed between ESR, CRP, RDW, NLR, PLR, PLT, and DAPSA scores, while no statistically significant association was found for MPV. The findings indicated that inflammatory and hematological markers can be helpful factors in evaluating the severity of psoriasis and psoriatic arthritis.