Renal Function Assessment in the Elderly Using Plasma Creatinine Assay and Lean Body Mass Measurement

Not Applicable

• Conditions: Renal Function
• Interventions: Other: measurement of morphological parameters; Biological: a blood sample; Biological: albumin or blood in urine; Device: Dual X-ray absorptiometry (DXA); Device: Bioelectric Impedance Spectroscopy (BIS); Biological: 51Cr-EDTA plasma clearance

• Registration Number: NCT02288663
• Lead Sponsor: University Hospital, Strasbourg, France

Brief Summary

Glomerular filtration rate (GFR) is the recommended parameter to assess renal function. The reference technique to measure GFR (clearance of a glomerular agent) is not commonly used. Instead, estimations (eGFR) are routinely taken from serum creatinine (SCr) with several published formulae: Cockcroft and Gault, MDRD, CKD-EPI. Basically, all these formulae aim at predicting the endogenous creatinine production by morphological parameters (age, body weight...) However, in the elderly, muscular mass is extremely variable and sarcopenia is quite commonly encountered (frequently linked to Alzheimer disease). This is probably the main reason why the aforementioned formulae are not valid in this population: for a given renal function, a lower muscular mass induces a lower creatinine production and, henceforth, a lower SCr value, which gives an overestimation of eGFR.

Muscular mass is closely linked to lean body mass (LBM), which can be properly assessed by whole-body dual X-ray absorptiometry (DXA). Alternatively, Bioelectric Impedance Spectroscopy (BIS) can also be used.

Investigators postulate that it is possible to estimate GFR in the elderly from both SCr and LBM estimation from DXA. Proof of concept has already been made by others but until now, no specific formula for the elderly has been devised and properly validated.

Investigators'aim is thus to propose a new formula to predict GFR from both SCr and LBM (estimated from DXA) in the elderly. This formula will be elaborated from a first series of 100 patients and validated on a second series of 100 other patients.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2014-07-08
• Study Start: 2014-11-03
• Study First Submitted QC: 2014-11-06
• Study First Posted: 2014-11-11
• Status Verified: 2021-06
• Last Update Submitted: 2021-06-11
• Last Update Posted: 2021-06-14
• Primary Completion: 2022-11-02
• Study Completion: 2022-11-02

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 220

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Freage group	Bioelectric Impedance Spectroscopy (BIS)	only one group in this trial. All the participants will follow all the listed interventions.
Freage group	measurement of morphological parameters	only one group in this trial. All the participants will follow all the listed interventions.
Freage group	Dual X-ray absorptiometry (DXA)	only one group in this trial. All the participants will follow all the listed interventions.
Freage group	a blood sample	only one group in this trial. All the participants will follow all the listed interventions.
Freage group	albumin or blood in urine	only one group in this trial. All the participants will follow all the listed interventions.
Freage group	51Cr-EDTA plasma clearance	only one group in this trial. All the participants will follow all the listed interventions.

Primary Outcome Measures

Name	Time	Method
SCr and LBM estimated from DXA	Each participant is followed for one day.	The formula that will be designed (using SCr and LBM estimated from DXA) from the first 100 patient data, will match measured GFR (as given by 51Cr-EDTA clearance) with less than 10 mL/min/1.73 m² absolute error in more than 90% of the other 100 patients.

Secondary Outcome Measures

Name	Time	Method
Sensitivity of new formulae	Each participant is followed for one day.	The new formulae outperform eGFR (Cockcroft and Gault, MDRD and CKD-EPI formulae) for the following criteria: sensitivity to detect GFR \< 60 mL/min/1.73 m²
Specificity of new formulae	Each participant is followed for one day.	The new formulae outperform eGFR (Cockcroft and Gault, MDRD and CKD-EPI formulae) for the following criteria: specificity to detect GFR \< 60 mL/min/1.73 m²
SCr and lean body mass ( by DXA)	Each participant is followed for one day.	Detection of patient with impaired renal function by measuring SCr and lean body mass by DXA better than with existing formulas.
SCr and lean body mass (by BIS)	Each participant is followed for one day.	A formula using SCr and measurement of lean body mass by bioelectric impedance spectrometry that will match measured GFR (as given by 51Cr-EDTA clearance) with less than 10 mL/min/1.73 m² absolute error in more than 90% of the other 100 patients.
SCr and morphological parameters	Each participant is followed for one day.	A formula using SCr and measurement of morphological parameters (thigh perimeter, leg perimeter, arm perimeter) that will match measured GFR (as given by 51Cr-EDTA clearance) with less than 10 mL/min/1.73 m² absolute error in more than 90% of the other 10
Accuracy of new formulae	Each participant is followed for one day.	The new formulae outperform eGFR (Cockcroft and Gault, MDRD and CKD-EPI formulae) for the following criteria: better accuracy (smaller bias) according to Bland and Altman
Precision of new formulae	Each participant is followed for one day.	The new formulae outperform eGFR (Cockcroft and Gault, MDRD and CKD-EPI formulae) for the following criteria: better precision (smaller SD of difference) according to Bland and Altman.

Trial Locations

Locations (1)

Hôpitaux Universitaires de Strasbourg; 🇫🇷 Strasbourg, France