Have you ever had a kidney stone? If you have, I’m sure you don’t want another one. I’ve heard patients compare kidney stone pain to the pain of childbirth or being stabbed. Unfortunately, up to 50 percent of people who have had one kidney stone will have another in the following 15 years, and kidney stones account for more than one million emergency room visits each year.
What Exactly Are Kidney Stones?
Let’s talk about what kidney stones are and why the recurrence rate is so high. Then I’ll let you know about the research my team is doing to try to bring this recurrence number down.
Kidney stones are solid deposits of minerals and salts that build up in the urinary tract. There are several reasons why this buildup happens, including inadequate fluid intake, metabolic problems, or dietary factors (such as a high salt or high protein diet). Family history of kidney stones is also a risk factor.
If you’re lucky, a small kidney stone can pass out of the body with little or no pain, but a larger stone can be excruciating when it moves into the ureter, blocking urine flow and causing pressure to build up in the kidney.
Should I Drink More Water?
When it comes to the amount of water an individual should drink, there is no magic goal, as one's needs vary depending on age, weight, level of physical activity, general health, and climate. Most people who never form kidney stones are probably drinking enough liquid to keep the concentration of their urine in the right zone and flowing normally.
In many kidney stone formers, the concentration of urine may be off. While this may sound like an easy problem to fix – drink more water to prevent another kidney stone, right? – a change in fluid intake is much more challenging than it sounds for a lot of stone formers.
In other words, even though it is well known that increased fluid intake can decrease the chance of a second kidney stone after the first one, many kidney stone formers struggle with maintaining that higher fluid intake level long-term. They may do it for a few weeks or a few months after a stone episode, but then go back to their old habits.
The reasons behind this are variable – some patients simply forget to drink throughout the day, others may need to limit their bathroom breaks while they work and drink less water, and others just don’t like the taste of water.
What Motivates You?
Whatever the case, most patients who have had a kidney stone need to drink more water for the rest of their lives to help prevent another one, and my research team is studying how to help them do that. In particular, we want to find out what works best to motivate stone formers to change their behavior for the long-term.
Through a clinical trial sponsored by the National Institutes of Health, we’re testing three different interventions to increase and maintain high fluid intake and to reduce kidney stone recurrence: 1) use of a smart water bottle that helps participants track their fluid intake and remind them to drink if they are behind during the day; 2) a modest financial incentive as a reward every day they meet their fluid intake goal; and 3) access to a health coach who helps them identify and overcome their barriers to drinking more fluids.
It will be fascinating to see if these interventions work. My hope is that we will get closer to understanding what’s most effective so we can help the millions of patients who suffer from recurring kidney stones.