Validity of synovial fluid lipid parameters and Apolipoprotein a1 as biochemical markers of advanced knee osteoarthritis among middle Euphrates Iraqi women

Background: Several biomarkers are examined to predict the severity and advanced stages of knee osteoarthritis, however; yet, no biomarker is the optimal one. With some advantages and disadvantages. In Iraq, there is a lack in the studies that investigated lipid profile in the synovial fluid and its role in the assessment of Knee Osteoarthritis (KOA) severity or grade. Objective: To assess the validity of lipid profile parameters and Apolipoprotein A1 as biochemical markers for progression of knee osteoarthritis among Middle Euphrates Iraqi Women. Patients and Methods: A cross-sectional study conducted in Al-Najaf Al-Ashraf Teaching Hospital and Al-Sader Teaching Hospital, in Al-Najaf City during a period 2021-2023, included 118 Women with KOA of Kellgren-Lawrence (KL) grades 2 to 4. Synovial fluid and blood samples were collected and sent for laboratory investigations. Data were analyzed using the statistical package for social sciences version 28 at a significance level of 0.05. Results: The mean serum and synovial fluid Triglyceride (TG) levels were significantly higher, in Women with KL-grade 4 than those with KL grade 3 and grade 2. Serum and Synovial fluid HDL-C and APOA1 levels were significantly lower in Women with advanced KL grade, (P. value=0.001). Synovial fluid TG showed a sensitivity of 76.5%, specificity 73.2% and accuracy of 74.7%. The synovial fluid HDL-C showed a sensitivity, specificity and accuracy of 79.3%, 81.3% and 80.7%, respectively. Synovial fluid APO A1, had a sensitivity of 77.2%, specificity of 79.6% and accuracy of 79.7%. Conclusion: Synovial fluid high density lipoprotein cholesterol, triglycerides and Apolipoprotein A1 were good biochemical markers of advance knee OA and can be promising predictor in clinical evaluation and follow up of diseases progression among Iraqi patients with knee OA.