Early Coaching to Increase Water Intake in CKD.

Area of Science:

• Nephrology
• Internal Medicine
• Public Health

Background:

• Observational studies suggest increased water intake benefits kidney function, but evidence in advanced chronic kidney disease (CKD) is limited.
• Previous trials on coaching to increase water intake (CIWI) showed nonsignificant declines in kidney function.
• The hypothesis is that CIWI may benefit CKD stages 1-2 (G1 and G2) and is dependent on functional renal reserve (RFR).

Purpose of the Study:

• To determine the effectiveness of CIWI based on estimated glomerular filtration rate (eGFR) stage and RFR in adults with CKD stages 1-2.
• To evaluate the impact of CIWI on kidney function, urine albumin/creatinine ratio, and quality of health (QH).

Main Methods:

• A prospective multicenter randomized trial (ECIWIC) based on the CKD WIT trial.
• Four groups (31 patients each) with CKD G1 and G2, with and without CIWI, were studied over 12 months.
• Primary outcome: change in eGFR; Secondary outcomes: urine albumin/Cr ratio and QH. RFR was assessed using an oral saline solution.

Main Results:

• No statistically significant eGFR changes were observed overall, but trends suggested CIWI improved eGFR in CKD G1 and preserved it in CKD G2.
• Patients with RFR >50% showed preserved or increased eGFR with CIWI, while those with low RFR experienced eGFR decline.
• Quality of health was preserved in CIWI groups (G1 and G2) but declined in control groups.

Conclusions:

• CIWI preserves renal function in CKD G1 and prevents decline in CKD G2, especially when RFR is above 50%.
• The ECIWIC trial indicates CIWI benefits patients with early-stage CKD and preserved RFR.
• Individual RFR assessment is crucial for predicting CIWI effectiveness in CKD patients.