MedicalResearch.com: What is the background for this study? What are the main findings?
Response: This study is about the use of increased water intake in people with chronic kidney disease (CKD).
Although there are a large number of benefits claimed most are not substantiated by evidence. However there is a growing body of evidence (animal and human observational studies) that increased hydration with the suppression of antidiuretic hormone preserves kidney function in CKD. This led to our current randomised clinical trial of 631 patients with stage 3 CKD and proteinuria to determine if drinking an extra 4-6 glasses of water per day for 1 year would slow their progressive loss of kidney function as measured by eGFR.
The main findings were that those coached to increase their water intake versus those coached to sustain their normal fluid intake suffered no ill effects from the intervention and on average were able to sustain an average increase of approximately 3 glasses of water per day. At the end of 1 year the increased hydration group had suppressed their antidiuretic hormone levels (copeptin) significantly but did not demonstrate a greater preservation in their eGFR.