Diferencias entre los métodos de determinación de 2.a y 3.a generación de la parathormona sérica sobre la mortalidad en el paciente en hemodiálisis

摘要

Parathormone plays a key role in controlling mineral metabolism. PTH is considered a uremictoxin causing cardiovascular damage and cardiovascular mortality in dialysis patients.There are two different assays to measure PTH called 2nd generation or intact PTH (iPTH)and 3rd generation or bioPTH (PTHbio).Objective: To evaluate the differences in mortality of dialysis patients between both assaysto measure PTH, as well as the possible prognostic role of the PTHbio/iPTH ratio.Methods: 145 haemodialysis patients were included with 2-year monitoring including baselinelaboratory test and annually thereafter.Results: 21 patients died in the first year and 28 in the second. No correlation was foundbetween PTH, PTHbio and PTHbio/iPTH ratio with mortality. Both PTH have a perfect correlationbetween them and correlate similarly with other molecules of the mineral metabolism.The extreme baseline values of PTH are those of higher mortality. In survival by iPTH intervals(according to guidelines and COSMOS study), a J curve is observed. When iPTH increases,the ratio decreases, possibly when increasing fragments no. 1–84. There is no greaterprognostic approximation on mortality with PTHbio than PTHi. There was also no differencein mortality when progression ratio PTHbio/PTHi was analysed.Conclusions: We didn’t find any advantages to using bioPTH vs. PTHi as a marker of mortality.BioPTH limits of normality must be reevaluated because its relationship with iPTH is notconsistent. Not knowing these limits affects its prognostic value