A systematic review to determine the most effective interventions to increase water intake.

BACKGROUND: Maintaining adequate fluid intake has been hypothesized to be beneficial for the progression of chronic kidney disease (CKD). The aim of this study was to undertake a systematic review to determine the most effective interventions to increase water intake.

METHODS: Six electronic databases were searched from 1910 until March 2015 in the English language. Additional sources through hand-searches, expert recommendations and reviews were checked. Intervention studies increasing water intake in adults through non-pharmacological methods were eligible for inclusion. The quality of included studies was assessed.

RESULTS: A total of 950 studies were found of which 16 met the inclusion criteria. Eight studies were randomized controlled trials, and seven studies spanned 6 months or longer. The study populations varied and included patients with recurrent nephrolithiasis (n = 6), autosomal dominant polycystic kidney disease (n = 3), CKD (n = 1), urinary tract infection (n = 1) and other miscellaneous conditions (n = 5). The quality of the studies was mostly neutral (63%) with no studies of high quality. Interventions ranged from instruction alone to self-monitoring tools, providing water bottles and counselling and education. Most interventions successfully increased water intake with 13 studies reporting an increase of at least 500 mL. The most effective strategies were instruction and self-monitoring using urine dipstick or 24 h urine volume.

CONCLUSION: All interventions carried out in the studies succeeded in increasing water intake, with none leading to decreases in intake, and these could be implemented in potential clinical trials in CKD. However, more high quality long-term intervention studies are required to further validate findings.