Evaluation of bone mineral status with dual-energy x-ray absorptiometry and quantitative computed tomography in chronic renal disease

Background and Aims Mineral and bone disease (BMD) is one of the common complications of advanced chronic kidney disease (CKD). Fracture risk could be predicted by bone densitometry using dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT). This study aims to evaluate the effectiveness of imaging techniques in diagnosing BMD in CKD patients and healthy subjects. Method We performed control cross-sectional study in single center in Turkey between 2019, and 2022. We evaluated two groups aged 18-50 years. Patients groups; consisted of patients with stage 4 -5 chronic kidney disease, and control healty groups; consisted of healty participants. The bone status of thirty-three participants was evaluated using both cQCT and DXA. Diagnostic discordance was assessed between the lumbar spine and femoral neck from DXA and cQCT. Results Thirty-eight participants were included in the study and BMD of 33 was evaluated with DXA and cQCT. The median age was 44 years (range 22-50) in the patient's group (33% female), and 42 years (range 27-48) in controls (55% female). Baseline variables were outlined in Table 1. Using the DXA T score and cQCT; the incidence of osteopenia or osteoporosis was not statistically different in the patient and control groups (for DXA; spine and femoral neck, p: 0,62 and 0,61 respectively, for cQCT; spine and femoral neck, p:0,8 and 0,73 respectively). Regarding the lumbar spine, DXA diagnosed osteopenia or osteoporosis more frequently compared to QCT in the patient's group [6 (40%) vs 3 (20%), p = 0,01]. Three of 6 patients (50%) diagnosed with osteopenia or osteoporosis by DXA were evaluated as having normal bone status by QCT. There was no statistical difference between the two methods in the control group. The results of bone status in lumbar spine and femoral neck in the whole cohort were summarized in Table 2. Conclusion According to our result, in young or middle-aged patients with stage 4-5 CKD, DEXA might overdiagnosis osteopenia or osteoporosis compared to QCT.