Determination of the parathyroid hormone reference interval in patients with different stages of the chronic kidney disease

Abstract

Secondary hyperparathyroidism (SHPT) is one of the most clinically significant complications of chronic kidney disease (CKD) due to associated mineral, bone disorders, and metastatic calcification. The indicators of mineral and bone metabolism of 635 patients with different CKD stages and 50 persons of the control group were analyzed using a neural network algorithm and the mathematical technology BootStrаp, which allowed determining the target PTH intervals for each stage in patients with CKD, corresponding to the optimal indicators of mineral density and metabolism bone tissue, in order to improve the survival of this category of patients. It was found that the upper limit of the reference interval of the PTH level in patients with CKD and GFR > 35 ml/min coincides with the general population, in patients with CKD and GFR 15‒35 ml/min it is 185 pg/ml, which is 3 times higher than in the general population, and in patients with CKD and GFR < 15 ml/min it is 500 pg/ml (7.5 times higher than in the general population). In dialysis patients with the PTH level of 500‒1500 pg/ml, it is possible to maintain satisfactory parameters of bone metabolism, and the PTH level of >1500 pg/ml determines the extreme risk of developing severe SHPT complications.