Relation between serum IL-17 level and risk of osteoporotic fracture in premenopausal rheumatoid arthritis patients: Clinical,radiological and laboratory studies

IntroductionOsteoporosis is a main extra-articular complication of rheumatoid arthritis (RA) which may lead to fractures. Interleukin-17 (IL-17) is one of the cytokines which plays a significant role in RA pathogenesis and promotion of osteoporosis.Aim of the workTo study the relation between serum IL-17 levels and the risk of osteoporotic fractures in pre-menopausal RA patients.Patients and methodsTwenty-five premenopausal RA patients and 20 matched healthy controls were included in this study. All patients were subjected to detailed history taking, thorough clinical examination, disease activity assessment using the disease activity score-28 (DAS-28) and disability was assessed using Health Assessment Questionnaire–Disability Index (HAQ-DI). Bone mineral density and serum IL-17 levels were measured in patients and the control. Fracture Risk Assessment Tool (FRAX index) was also calculated.ResultsThe mean age of RA patients was 38.8 ± 7.6 years. The BMD was significantly reduced in patients compared to the control at the femur neck (p = 0.008), wrist (p = 0.046) and at the lumbar spine (p = 0.005). The Z score was below the expected range for age in 36% compared to 5% in the control (p = 0.03). Serum IL-17 concentrations were significantly higher in patients (5.99 ± 1.22 pg/ml) compared to the control (3.73 ± 2.15 pg/ml) (p < 0.001). Serum IL-17 levels showed a significant correlation with FRAX scores. Z-score interpretation showed a strong positive significant correlation with FRAX index; major osteoporotic fractures and hip fracture (p = 0.005 and p = 0.013, respectively) in patients.ConclusionThe premenopausal Rheumatoid arthritis patients showed a high fracture probability. Interleukin-17 serum level is associated with higher liability to fractures among rheumatoid patients.