For many of our patients, frequent UTIs can be a big source of discomfort and frequent ED or PMD visits.  Women, in particular, are impacted by this issue as they have >50% lifetime risk of acute cystitis.  Many are treated with antibiotics which may or may not be appropriate (don’t worry, that is a much bigger topic than can be encapsulated in a TR pearl, but do society a favor and check the hospital’s antibiogram before sending your Rx).

There are multiple commonly held beliefs about how to prevent UTIs including cranberry juice or extract, voiding after intercourse, and drinking more water.  A randomized controlled study from JAMA internal medicine published in October 2018 (see reference below) sought to play Mythbuster (side note: if you don’t know about this show, you should) and looked at whether or not drinking more water actually decreased the frequency of UTIs.

Before presenting the numbers, a major disclaimer is necessary: this study was funded by a company that sells bottled water.  While the study did not investigate bottled versus tap water, it is still an obvious conflict.

That being said, researchers found several interesting things.  The study randomized 140 premenopausal women with at least 3 episodes of cystitis in the previous year who self-reported drinking less than 1.5 L of fluid per day into 2 groups.  One group drank an additional 1.5 L of fluid and the other did not.  In the group with additional fluid, the mean number of episodes of cystitis decreased from 3.2 in the control group to 1.7 in the experimental group.  The mean number of antimicrobials prescribed also decreased from 3.6 in the control group to 1.9 in the experimental group.

There are a number of issues with this study, including the funding source as mentioned above, but also the self-reporting nature of data collection.  However, drinking more water is generally safe, cheap and easy.  It might save your patient an additional visit or two.



Effect of Increased Daily Water Intake in Premenopausal Women With Recurrent Urinary Tract Infections: A Randomized Clinical Trial. JAMA Intern Med. 2018 Oct 1. doi: 10.1001/jamainternmed.2018.4204.