High Serum Sclerostin Levels Are Associated with a Better Outcome in Haemodialysis Patients

Abstract

Background: Sclerostin is an osteocyte hormone that decreases osteoblastogenesis. Sclerostin may play a key role in osteoporosis and also in vascular calcification (VC). In chronic kidney disease and haemodialysis (HD) patients, serum sclerostin levels are high. Aim: To assess the correlation of serum sclerostin levels with VC, bone mineral density (BMD), and survival rate in HD patients. Methods: A cross-sectional study was conducted in prevalent HD patients to correlate serum sclerostin tertiles with the Kauppila aortic calcification score, BMD scores and survival rate. Results: We studied 207 patients who had a mean serum sclerostin level of 1.9 ± 0.7 ng/ml. Compared to patients in the 1st tertile of serum sclerostin levels (0.6-1.53 ng/ml), patients in the 3rd tertile (2.2-4.6 ng/ml) were significantly older (73.7 ± 12 vs. 64.7 ± 18 years), more frequently of the male gender (74 vs. 48%), had lower serum bone-specific alkaline phosphatases values (14 ± 9 vs. 20.4 ± 13 µg/l), were less frequently treated with alfacalcidol, displayed lower aortic calcification scores (9.5 ± 5 vs. 12.5 ± 7/24) and had higher BMD scores. Furthermore, patients of the 3rd tertile displayed a lower mortality rate compared to tertile 1 using multivariable adjusted Cox model (hazard ratio 0.5, 95% CI 0.25-0.93, p = 0.03). The main factors associated with VC score were age, diabetes, cardiovascular disease, CRP level and Warfarin use. Conclusion: Our study of HD patients shows that higher serum sclerostin levels are associated with higher BMD, lower aortic calcification scores, and a better survival rate.