SAT0657 MONOCYTE-LYMPHOCYTE RATIO AND PLATELET-LYMPHOCYTE RATIO: ROLE AS BIOMARKERS OF DISEASE ACTIVITY IN PSORIATIC ARTHRITIS PATIENTS
Authors: Raquel Ferreira, Sara Ganhão, Bruno Miguel Fernandes, Salomé Garcia, Sofia Pimenta, Miguel Bernardes, Lúcia Costa
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Monocyte-lymphocyte ratio (MLR), neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) had emerged as good indicators of systemic inflammation status in a variety of diseases like cancer, cardiovascular and autoimmune diseases. Furthermore, some recent data showed relevant association of this haematological parameters with others traditional inflammatory measures as serum c- reactive protein (CRP) levels in rheumatic patients, suggesting their use as a valuable indicator of disease activity. <h3>Objectives</h3> To assess the association between the NLR, MLR, eosinophil-lymphocyte ratio (ELR), basophils-lymphocyte ratio (BLR) and PLR with disease activity and functional parameters in psoriatic arthritis (PsA) patients. <h3>Methods</h3> An observational cross-sectional study was performed in patients with psoriatic arthritis before introduction of a bDMARD, followed at our Rheumatology department until December 2018. Demographic, clinic and laboratory information were collected from the national database (Reuma.pt). Available data of blood cell counts were consulted and NLR, MLR, ELR, BLR and PLR were calculated by dividing neutrophil, monocyte, eosinophil, basophils and platelet count by lymphocyte count, respectively. The following disease activity and functional scores were also registered: CRP and ESR levels, DAS28 4V and 3V (ESR and CRP), HAQ, BASDAI, ASDAS-CRP, BASFI, BASMI, swollen and tender joints counts (SJC and TJC), SPARCC index, patient global assessment (PtGA) and physician global assessment (PGA) rated on a visual analogue scale (VAS). Correlations between variables were evaluated with Spearman's test. The statistical analysis was performed using SPSS 21.0 software. Differences were considered statistically significant at p&lt;0.05. <h3>Results</h3> A total of 83 patients were enrolled. Forty-three were females (51.8%) and forty were males (48.2%). The mean age was 47 years (±10.9) 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%). Thirty patients presented with dactlylitis (36%). Most were non-smoking (n=48; 57.8%) and most didn't have history of alcohol consumption (n=55; 66.3%). According to ASDAS criteria, 25 patients (30.1%) had high disease activity and 45 patients (54.2%) very high disease activity. At time of evaluation, 71.1% were receiving csDMARDs. NSAIDs and corticosteroids were prescribed in 80.7% and 54.2% of the patients, respectively. We found statistically significant correlation between MLR values and CRP levels (r=0.276, p=0.014). MLR did not correlate with ESR levels, DAS28 4V and 3V (ESR and CRP), HAQ, BASDAI, ASDAS-CRP, BASFI, BASMI, SJC, TJC, SPARCC, PtGA and PGA. PLR values also had weak correlation with ESR (r=0.340, p=0.002), DAS 4V-ESR (r=0.260; p=0.027) and with DAS 3V-ESR (r=0.290, p=0.012). There was no statistically significant correlation between PLR values and others disease parameters. No significant correlation were found between NLR, ELR and BLR and the functional and disease activity scores evaluated. <h3>Conclusion</h3> Our study showed that MLR had a positive association with CRP and PLR with ESR, DAS 4V-ESR and DAS 3V-ESR. Evaluation of this novel inflammatory biomarkers may represent a simple, cost-effective and useful tool in monitoring disease activity in PsA patients. <h3> Disclosure of Interests</h3> None declared