POS1114 LABORATORY BIOMARKERS OF JOINT REMODELING AND INFLAMMATION IN PATIENTS WITH EARLY KNEE OSTEOARTHRITIS

Abstract

BackgroundRecord prevalence of osteoarthritis (OA) around the world is aggravated by the fact that doctor most often meets it on advanced stage, so that therapeutic interventions can no longer provide significant success [1]. It is advisable to study early joint remodeling, when gross irreversible changes have not yet occurred, and laboratory markers appear to be valuable diagnostic and prognostic tool, potentially able to identify patients-responders to particular treatment method [2].ObjectivesTo verify joint tissue remodeling and synovitis in patients with early knee OA Kellgren-Lawrence (K-L) Grades 0-2 using laboratory biomarkers.MethodsThe study included 90 patients with knee OA K-L Grades 0-2 (3 groups of 30 people each) and 30 healthy volunteers; to clarify early OA, Luyten FP criteria (2018) were used [3]. Among persons with knee OA, there were 57 women (63.3%) and 33 men (36.7%), mean age 32 [27; 35] years; participants without OA were presented by 18 (60%) men and 12 (40%) women, mean age 29,5 [25; 34] years. Knee radiography, ultrasonography, laboratory biomarkers assessment including interleukin-1beta (IL-1b), N-Terminal Propeptide of Type 1 Procollagen (P1NP), Beta-Cross laps, cartilage oligomeric matrix protein (COMP) were carried out.ResultsAll groups with knee OA was characterised by women predominance (Table 1). Laboratory study revealed slight increase in IL-1β and both bone markers in K-L Grade 0. Grade 1 was characterized by elevation of COMP and Beta-Cross Laps on background of IL-1β increased. In Grade 2 the highest level of COMP, slight decrease in Beta-Cross Laps and IL-1β, weak increase in P1NP were found. Correlation analysis have detected positive significant relationships between COMP and IL-1β (r=0.37), as well as Beta-Cross Laps and P1NP (r=0.43). The analysis of laboratory and instrumental relationships demonstrated significant correlation between COMP and medial condyle cartilage thickness (r=-0.18), COMP and bursa suprapatellar square (r=0.26), Beta-Cross Laps and osteophytes size (r=0.79), IL-1β and synovial membrane thickness (r=0.24).Table 1.Comparative analysis of clinical and laboratory parameters in patients of different knee OA Grades and volunteersParameterVolunteer groupKnee OA groupsSignifican-cy, p-valueK-L Grade 0K-L Grade IK-L Grade II012345GenderМ-18 (60%)F-12 (40%)М-13 (43,3%)F- 17 (56,7%)М-10 (33,3%) F -20 (66,7%)М-10 (33,3%)F -20 (66,7%)1-3: 0,0381-4: 0,038Mean age, years29,5 [25; 34]26 [20; 32]39 [36; 44,5]45 [43,5; 48]1-4: 0,049 2-4: 0,038СОМР, ng/ml527,3[355,1;576,5]495,7[421,9;737,2]737,5 [660,2; 1033]1683,5[1288,4; 2260,1]1-3: 0,0441-4: 0,002 2-4: 0,0113-4: 0,058P1NP, ng/ml58[51,3; 64,3]98,2 [72,4; 126,1]101,3[85,0; 123,4]117,1[105,1; 142,7]1-2: 0,042 1-3: 0,0391-4: 0,024Beta-Cross Laps, ng/ml0,545[0,466;0,645]0,697[0,656; 0,861]0,939 [0,823; 1,497]0,793[0,697; 1,032]1-3: 0,0321-4: 0,044 2-4: 0,092IL-1β, pg/ml3,7 [2,5; 6,0]7,3 [5,0; 16,3]19,1 [15,4; 29,5]10,4 [8,6; 20,2]1-3: 0,0121-4: 0,028ConclusionEarly knee OA of K-L Grade 0 is characterized by bone metabolism activation and synovial inflammation before articular cartilage involvement. On Grade 1, cartilage destruction appears and bone resorption is enhanced. Grade 2 is characterized by significant intensification of cartilage destruction, weakening of bone resorption on the background of synovial inflammation. In addition to cartilage damage, COMP is associated with joint inflammation, which requires further research to take in account it as also synovial biomarker.