AB1312 TIME-COURSE CHANGE OF NEUTROPHIL-LYMPHOCYTE RATIO, MONOCYTE-LYMPHOCYTE RATIO AND PLATELET-LYMPHOCYTE RATIO IN PSORIATIC ARTHRITIS PATIENTS AND RESPONSE TO BIOLOGIC THERAPY

Abstract

Background Recently, systemic inflammation has been shown to be a key determinant of prognosis. Neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), and platelet-lymphocyte ratio (PLR) has been related to inflammation status and suggested as additional markers of response to bDMARDs in patients with rheumatoid arthritis. However, few studies were yet developed about this subject in psoriatic arthritis (PsA). Objectives The aim of this study was to investigate the time-course change of NLR, MLR and PLR levels in PsA patients after 6 and 12 months of bDMARD therapy and to evaluate their clinical significance and utility in monitoring response to biologic agents. Methods An observational retrospective study was performed in patients with PsA under bDMARD, followed at our Rheumatology department until December 2018. Demographic and clinical data were collected from the national database. C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and total blood count were consulted before and after 6 and 12 months of biologic treatment and NLR, MLR and PLR were calculated by dividing neutrophil, monocyte and platelet count by lymphocyte count, respectively. Disease activity was evaluated with DAS28 and ASDAS. The variation of each parameter was calculated as the difference between the levels registered at 6 and 12 months and the baseline and presented as Δ. Correlation between ΔNLR, ΔMLR and ΔPLR with ΔCRP and ΔESR levels, ΔDAS28 and ΔASDAS was calculated using the Spearman’s test. Results A total of 83 patients were included. Forty-three were females (51.8%). The mean age at diagnosis was 41 years (±11.3) and the median disease duration at start of biological therapy was 6.9 years (min:1.4; max:32.4). In total, 67.5% of the patients had axial involvement (n=56), 91.6% articular involvement (n=76) and 43.4% enthesopathic involvement (n=36). Almost all patients fulfilled the CASPAR criteria for PsA (n=78; 94%). At the baseline, 25 patients (30.1%) had high disease activity and 45 patients (54.2%) very high disease activity according to ASDAS criteria. The most used bDMARD was etanercept (n=29; 35%), followed by golimumab (n=26; 31%), adalimumab (n=16; 19%) and infliximab (n=8; 10%). Certolizumab was administered to 2 patients and secukinumab to others 2 patients. Fifty-nine patients were concomitantly treated with csDMARDs. The median value of CPR was 1.5mg/dL [0.03-30], 0.26 [0.03-11] and 0.37 [0.02-19] at baseline, 6 and 12 months, respectively. The median value of ESR was 33mm/hr [4-98], 11 [2-75] and 10 [1-68] at baseline, 6 and 12 months, respectively. We realize that NLR, MLR and PLR decreased after 6 months of treatment and remained relatively stable at 12 months (NLR median: 2.6 [0.1-8.8], 1.6 [0.5-5.3], 1.6 [0.5-8]; MLR median: 0.32 [0.11-250], 0.23 [0-7.4], 0.25 [0.05-1]; PLR median: 132 [69.6-342.5], 97.6 [33.4-415.1], 98.6 [ 38.3- 528.6] at baseline, 6 and 12 months, respectively). A significant positive correlation was found between ΔNLR and ΔCPR at 6 months (r=0.272; p=0.016) and also between ΔMLR and ΔCPR at 6 and 12 months (r=0.309, p=0.006; r=0.364, p=0.002). ΔPLR showed a statistically significant correlation only with ΔESR at 6 months (r=0.312; p=0.006). No correlation were found between ΔNLR, ΔMLR and ΔPLR with ΔDAS28 or between ΔNLR, ΔMLR and ΔPLR with ΔASDAS at evaluation of 6 and 12 months. Conclusion Our data showed that NLR, MLR decreased promptly in parallel with decrease of CRP and PLR with ESR for up 6 months of therapy with biologics. This results, in agreement with the literature, suggests that NLR, MLR and PLR may be seen as a useful marker for demonstrating systemic inflammation in PsA patients. Further studies are needed to better emphasize the importance of these parameters and to evaluate their utility to monitor the effectiveness of biologic therapy. Disclosure of Interests None declared