High water vs. ad libitum water intake for autosomal dominant polycystic kidney disease: a randomized controlled feasibility trial
Publication: QJM: An International Journal of Medicine
R El-Damanawi, M Lee, T Harris, L B Cowley, S Bond, H Pavey, R N Sandford, I B Wilkinson, F E Karet Frankl, T F Hiemstra
Vasopressin is a hormone that is made by the body to conserve water in states of dehydration. In Polycystic Kidney disease (PKD) this hormone accelerates cyst growth and kidney damage, making it the fourth leading global cause of kidney failure. High water intake reduces blood levels of vasopressin, and may slow cyst growth and disease progression similarly to currently available vasopressin blockers. However, the feasibility, safety and sustaintability of this therapeutic strategy remains unknown.
In this randomised controlled trial, patients with PKD were randomised to either high water intake (HW) or Ad libitum water intake (AW) over an 8-week period. The primary outcome was to determine if the HW group could maintain dilute urine, and the AW group could keep their urine more concentrated over an 8-week follow up period. We used a self-management strategy and smartphone applications to promote compliance.
Researchers found that high water intake is feasible, sustainable and safe, and can be started early in the disease course prior to the onset of irreversible kidney damage; while the use of smartphone applications to record home-monitoring of urine dipstick tests promoted adherence, driving a difference in urine results between the groups. A definitive global randomised controlled trial of high versus normal water intake is possible and will be the next stage of this work.
