The Longitudinal PTH-Study

Secondary Hyperparathyroidism Clinical Trial

Official title:

Intact Versus Biointact Assays for Longitudinal Assessment of Parathyroid Hormone - The Longitudinal PTH Study

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03464149
• Other study ID #: The Longitudinal PTH-Study
• Status: Completed
• Start date: March 20, 2018
• Est. completion date: August 7, 2019

Study information

• Verified date: June 2020
• Source: Medical University of Vienna
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The main study aim is to quantify the agreement between the analytical results provided by two third generation and two second generation Parathyroid hormone (PTH) assays. The primary comparison will be performed between the second-generation PTH assay"Intact PTH assay" from Siemens Healthcare Diagnostics Inc. and the third-generation PTH assay "biointact (1-84)" from Roche Diagnostics in terms of a Bland-Altman analysis. Several studies have evaluated the correlation between various PTH assays at a single time-point, but no previous study has tested the hypothesis that longitudinal changes in PTH levels, which are important for making treatment decisions, can be monitored by several PTH assays alike. To this aim, the key secondary objective is to analyze the longitudinal variance in PTH over the course of 1 year, using each of two assays of the second and third generations, respectively. Other secondary objectives include determining changes in serum phosphate, serum calcium, fibroblast growth factor 23 (FGF23), with respect to treatment decisions. For clinical applicability of the results to be obtained here, an important goal of the present study will be not to influence treatment decisions, which will remain independent of the study investigators, at the full responsibility of the hemodialysis physicians.

At every quarterly blood draw over the course of one year, the investigators will freeze the serum from 100 patients, and at the end of 4 quarters the investigators will analyze PTH-levels using the following assays: Intact Parathyroid Hormone (Advia Centaur, Siemens Healthcare), PTH-Intact (Cobas, Roche), PTH (1-84) - The agreement between the PTH assays will be analyzed at baseline, as well as at the subsequent quarterly evaluation time-points by Bland-Altman analysis and complemented by Passing-Bablok regression. The longitudinal changes in PTH will be displayed graphically and analyzed by estimating the within-patient variance across time, the between patient variance at each time-point as well as effects on the mean log-PTH level due to course of disease and therapeutic interventions from a linear mixed model.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 132
• Est. completion date: August 7, 2019
• Est. primary completion date: December 5, 2018
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• All patients who were undergoing uninterrupted hemodialysis or hemodiafiltration at the Chronic Hemodialysis Unit of the Division of Nephrology and Dialysis, Medical University of Vienna between November 1st, 2017 and December 31st, 2018.

• Existence of residual blood samples from four successive quarterly routine controls

• Age = 18 years

• The test result of the assay must not have any diagnostic value or therapeutic consequence for the patients included in this study.

Exclusion Criteria:

• Death during the observational period (all patients must have lived through the 1-year period and must have all 4 quarterly blood draws performed on them).

• Age <18 years

Related Conditions & MeSH terms

• Bone Diseases
• Chronic Kidney Disease-Mineral and Bone Disorder
• CKD-MBD - Chronic Kidney Disease Mineral and Bone Disorder
• Hyperparathyroidism
• Hyperparathyroidism, Secondary
• Kidney Diseases
• Kidney Replacement
• Renal Insufficiency, Chronic
• Secondary Hyperparathyroidism

Intervention

Diagnostic Test:
• One armed study, blood from each patient is analysed by four assays ( two 3rd generation and two 2nd generation assays)
Intact PTH Assay (Siemens Healthcare Diagnostics Inc); LIAISON 1-84 PTH Assay (Diasorin); PTH (1-84), biointact (Roche Diagnostics); PTH, intact (Roche Diagnostics)

Locations

Country	Name	City	State
Austria	Department of Internal Medicine III, Division of Nephrology and Dialysis, Medical University of Vienna, Austria	Vienna

Sponsors (1)

Lead Sponsor	Collaborator
Medical University of Vienna

Country where clinical trial is conducted

Austria, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Longitudinal change in PTH levels measured in [pg/ml]	PTH levels as measured by the second and third generation assays	Timepoints of four consecutive quarterly routine controls per patient (month 1; month 4 ; month 8, month 12)
Secondary	Longitudinal within-patient change of PTH levels in [pg/ml]	Longitudinal within-patient variance of PTH over the course of 1 year, using each of two assays of the second and third generations, respectively.	Timepoints of four consecutive quarterly routine controls per patient (month 1; month 4 ; month 8, month 12)
Secondary	Serum Calcium levels	Serum Calcium levels	Timepoints of four consecutive quarterly routine controls per patient (month 1; month 4 ; month 8, month 12)
Secondary	Serum Phosphate levels	Serum Phosphate levels as measured by quarterly routine controls	Timepoints of four consecutive quarterly routine controls per patient (month 1; month 4 ; month 8, month 12)
Secondary	Fibroblast growth factor 23 (FGF23	Fibroblast growth factor 23 (FGF23) as measured in quarterly routine controls	Timepoints of four consecutive quarterly routine controls per patient (month 1; month 4 ; month 8, month 12)