AB0702 STANDARD AND HEMATOLOGICAL MARKERS OF SYSTEMIC INFLAMMATION IN PATIENTS WITH ELDERLY ONSET RHEUMATOID ARTHRITIS (EORA) AND YOUNG ONSET RHEUMATOID ARTHRITIS (YORA) - AN OBSERVATIONAL STUDY
Authors: S. Stojanović, B. Stamenković, J. Nedovic, J. Cvetkovic, I. Aleksic Milenkovic, N. Dimic, J. Jocic, A. Djindjic
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Rheumatoid arthritis (RA) is a systemic, inflammatory disorder with the peak incidence between the ages of 30 and 50. Elderly-onset rheumatoid arthritis (EORA) is defined as the onset of RA in individuals aged over 60 years and accounts for 10-33% of all RA. EORA differs from YORA in clinical course, degree of inflammatory response (IR) and joint destruction. Considering the impact of comorbidities and frequent infections in the elderly, which significantly affect the standard markers of RA, there is a need to define reliable, simple marker to properly assess the inflammatory activity of RA. <h3>Objectives:</h3> To compare the degree of inflammatory response (IR) in EORA and YORA measured by standard markers of inflammation (sedimentation rate-ESR and C reactive protein-CRP) and new hematological parameters of IR (Neutrophil-To-Lymphocyte-NLR and Platelet-To-Lymphocyte<b></b>-PLR), their interrelation, as well as the relationship with clinical disease activity index (CDAI). <h3>Methods:</h3> The study group consisted of 198 consecutive patients (81 EORA and 117 YORA). Parameters of IR (ESR, CRP, PLR and NLR), as well as disease activity index (CDAI) were recorded at the time of RA diagnosis. <h3>Results:</h3> The average age of all patients was 57.08±13.32 years (subgroup EORA: 73.06±14.12; subgroup YORA 41.5±10.13 years). The most of them were female (78.28%). EORA patients had significantly higher ESR and CRP (72 vs. 44mm/h and 16.0 vs. 7.2 mg/l; p=0.02). The absolute number of platelets did not differ between groups, while the absolute number of leukocytes was significantly higher in the EORA compared to the YORA group (7.0±2.4 vs. 8.3±2.7; p&lt;0.01). The NLR did not differ between groups, while PLR was significantly lower in EORA (169.1 vs. 216.8; p=0.03). We did not find a significant association between NLR and ESR, as well as NLR and CRP, but the PLR significantly correlated with standard parameters of IR: ESR and CRP (r=0.48 and r=0.44). EORA was characterized by significantly higher value of CDAI compared to YORA (32.7±16.7 vs. 22.4±7.8; p=0.01). In the multiple linear regression analysis, significant positive associations were confirmed in EORA patients for PLR with CDAI(b=0.59; p &lt;0.01). <h3>Conclusion:</h3> EORA and YORA represent distinct entities within the spectrum RA. The EORA group is characterized by higher conventional parameters of disease activity [clinical (CDAI) and laboratory (CRP and ESR)]. In our study, PLR was significantly lower in the EORA compared to the YORA group and represents a potential, simple marker that could facilitate the correct assessment of RA inflammatory activity, in addition to conventional inflammatory markers (ESR and CRP). The relevance of PLR and NLR in EORA requires further prospective observation studies. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>