Open Access Rheumatology: Research and Reviews (Jul 2024)
Autoantibodies Serum Level and 10-Year Risk of Fractures Evaluated by FRAX® Tool in Rheumatoid Arthritis Patients
Abstract
Rim Sghiri,1,* Hana Ben Hassine,2,* Mariam Ghozzi,2 Nejla El Amri,3 Khadija Baccouche,3 Rihab Sarraj,3 Zahid Shakoor,1 Adel Almogren,1 Elyes Bouajina3 1Immunology Unit, Department of Pathology, College of Medicine, King Saud University, Riyadh, Saudi Arabia; 2Immunology Laboratory, Farhat Hached Hospital, Sousse, Tunisia; 3Department of Rheumatology, Farhat Hached Hospital, Sousse, Tunisia*These authors contributed equally to this workCorrespondence: Rim Sghiri, Immunology Unit, Department of Pathology, College of Medicine, King Saud University, Riyadh, Saudi Arabia, Email [email protected]: FRAX® is a tool used for evaluation of risk of fracture in RA and non-RA patients and to identify those eligible for intervention. One of the limitations of FRAX in RA settings is that it does not consider factors known to contribute to osteoporosis such as autoantibodies. This study analysed the association of anti-mutated citrullinated vimentin antibody (anti-MCV), anti-cyclic citrullinated peptide antibody (anti-CCP), IgM rheumatoid factor (RF), IgA RF with 10-year risk of major osteoporosis and hip fracture.Methods: FRAX® tool was used to estimate 10-year risk of major osteoporosis fracture and hip fracture in 189 RA patients over 40 years of age. Anti-MCV, anti-CCP, IgM RF and IgA RF were tested using enzyme immunoassay and analysed at different levels. Results were adjusted for various confounders including disease activity.Results: Fifty-one (26.9%) RA patients had high (≥ 20%) 10-year risk of major osteoporosis fracture and 67 (35.4%) had high (> 3%) 10-year risk of hip fracture. Among all the tested autoantibodies, only IgM RF at elevated levels was associated with high 10-year risk of major osteoporosis fracture (adjusted OR = 4.1, 95% CI = 1.5– 11.3, p = 0.006) and of hip fracture (adjusted OR = 17.4, 95% CI = 3.7– 81.3, p < 0.0001). There was no agreement between FRAX and femoral neck (FN) BMD. None of the autoantibodies tested were associated with FN osteopenia or osteoporosis including IgM RF at high levels.Conclusion: Our study highlights the importance of quantitative measurement of autoantibodies in assessment of risk for fractures among RA patients. Our preliminary findings need to be assessed in prospective studies to determine the actual predictive value of high IgM RF levels among patients with RA.Keywords: osteoporosis, rheumatoid arthritis, 10-years risk of major osteoporosis fracture, 10-years risk of hip fracture, FRAX, anti-mutated citrullinated vimentin antibody, anti-cyclic citrullinated peptide antibody, rheumatoid factor, rheumatoid factor isotypes