The relationship between serum sclerostin and FGF-23 levels, bone mineral densitometry measurements and osteoporosis in hemodialisis patients

Introduction: As it is known, as the stage progresses in Chronic Kidney Disease, a process that starts with the accumulation of phosphorus in the plasma causes a process that progresses with hyperparathyroidism and later bone mineral disorders and decreased bone mass does not give significant symptoms before it reaches a serious size, and after this insidious process, it can cause a process with bone fractures in patients. In our study, we compared the measurement of FGF-23 and Sclerostin levels, two molecules found in current studies, with the BMD scores of the patients measured by DEXA. Although DEXA may give misleading results in CRF patients, significant results have been obtained in various recent literature results and it has been included in the diagnosis due to it's non-invasiveness and ease of application. Considering this process, we used the FRAX method in current studies, aiming to reach a more accurate result with the standardization of BMD. In this way, we aimed to measure the serum Sclerostin and FGF-23 levels in CKD patients and the control group, standardize the BMD values measured by DEXA with FRAX, to obtain a more accurate result and to see the effect of the high current values on the 10-year fracture risk. Materials and methods: In our prospective study, among the hemodialysis patients who applied to the Internal Medicine and Nephrology outpatient clinic of Düzce University Health Practice and Research Hospital between September 2022 and February 2023 and were treated at the hemodialysis center of our hospital, clinical and clinical studies were performed at a significance level of 5%, a power of 80%, and an effect size of 0.72. In order to obtain a statistically significant difference, a total of 40 cases in accordance with the study protocol and a control group of 26 healthy volunteers with similar age range and gender distribution were included in the study after obtaining informed consent. Patients under the age of 18, those with liver failure, acute infection, history of malignancy, pregnant women and patients with insufficient cooperation and orientation were excluded from the study. Due to the increased frequency of pathologies such as osteoporosis and osteodystrophy in CRF patients compared to the normal population, bone mineral densitometry is routinely performed at certain intervals. DEXA was performed for the measurement of bone mineral density, and demographic data were recorded, with the consent of the patients. Serum samples of venous blood samples taken during the normal follow-up of the patients, separated from the excess blood, were kept at -80 degrees, and Sclerostin, FGF-23 levels were measured with the Elisa method. Other parameters were taken from electronic and written archives as they were present in the examinations made in their routine follow ups. Results: While the groups are homogeneous in terms of age, they are heterogeneous in terms of gender. While the proportion of women in the hemodialysis group was significantly lower than the control group, the opposite finding was also obtained for men. Therefore, the parameters were evaluated separately in both genders. There was no significant difference between the groups in terms of other characteristics except weight, BMI, smoking and lifestyle (p>0.05). There was a significant difference in terms of Sclerostin, FGF-23 molecule and other criteria measured according to groups and gender (p<0.05). The BMD scores measured in the hemodialysis group were significantly lower than the values measured in the control group in both men and women. In addition, Sclerostin (p=0.001, p<0.001), FGF-23 (p<0.001), FRAX major Osteoporotic fracture (p<0.001), FRAX Hip Fracture (p=0.001) values measured in the hemodialysis group were significantly higher than the values measured in the control group in both men and women. Level was found to be higher. Conclusion: In our study, FGF-23 and Sclerostin levels measured in hemodialysis patients were found to be higher in both female and male patients compared to the control group, and BMD values measured with DEXA in these patients can be effective on the 10-year fracture risk by using the FRAX method and we are thinking the existing parameters can be used to predict the fracture risk. Keywords: Chronic kidney disease FGF-23, Sclerostin, osteoporosis, DEXA, FRAX