Emerging Role of Mobile and Smart Technology in the Prevention of Stone Disease

By: Vishnu Ganesan, MD and Deepak Agarwal, MD | Posted on: 01 Aug 2022

Introduction

Nephrolithiasis is an increasingly common medical condition, affecting nearly 1 in 11 people in the United States.¹ The cornerstone of stone prevention is dietary and medical management. Advancements in technology over the last decades have revolutionized how kidney stones are diagnosed and treated. Likewise, there has been an emergence of mobile and physical technology aimed at preventing stone disease.

Technologies to Increase Fluid Consumption

One of the tenets in the prevention of stone disease is increasing fluid intake. The AUA recommends an intake of enough fluid to produce 2.5 L urine daily; however, the adherence to this recommendation among patients is only 50%.² Interventions such as instruction and self-monitoring with urine dipsticks or measuring urine volumes have been shown to increase fluid intake behaviors of patients.³ Mobile health technologies may help overcome one of the common barriers, namely remembering to drink. There are over 50 applications in the Apple App Store that specifically target hydration. Most of these apps can provide notification reminders, keep a log of daily water intake and/or allow the user to set goals for their intake (see Table).

Table. Top rated (by mobile app rating scale score) applications for fluid and dietary management application

Rank	App (Fluid)	Cost	Mean Score	App Store Ratings
Fluid:
1	WaterMinder	$5.99	4.78	20,959 Ratings, 4.8 stars. Editor’s choice and #10 on Health and Fitness
2	Water Reminder’Daily Tracker	Free (in-app purchases)	4.4	39,751 Ratings, 4.7 stars
3	Plant Nanny 2	Free (in-app purchases)	4.22	70,312 Ratings, 4.7 stars
4	Drink Water Reminder, Tracker	Free (in-app purchases)	4.19	134,931 Ratings, 4.5 stars
5	BeWet	Free (in-app purchases)	3.96	33,100 Ratings 4.7 stars
Dietary:
1	Stone MD	Free (in-app purchases)	3.80	23 Ratings, 4.2 stars
2	oxaBrow	$4.99	3.73	5 Ratings, 2.6 stars
3	OxiPur	Free (in-app purchases)	3.52	266 Ratings, 4.5 stars
4	Reduce Stones	Free (in-app purchases)	3.48	N/A
5	Kidney Stone Symptoms & Treatment	Free (in-app purchases)	3.30	N/A
Adapted from Winoker et al.⁴ N/A, not applicable.

High-quality evidence to evaluate the effect of mobile applications on patient outcomes in urology is lacking. However, one group assessed the currently available applications using a standardized mobile health application rating system and ranked the available applications using this schema.⁴ One of the limitations of mobile applications is the burdensome task of manually entering fluid intake. The integration of smart devices such as wearables and water bottle technology has emerged as a solution to this challenge.

Figure. HidrateSpark PRO image. Image from Hydrate Inc.

One product is the HidrateSpark water bottle (Hydrate Inc., Minneapolis, Minnesota; see Figure). The device has an internal sensor that can calculate volume measurements by detecting changes in water level, which are then sent to the user’s smartphone. A randomized trial found that this device led to a significant increase in urine volume compared to dietary counseling alone.⁵ Other smart water bottles include the H2OPal (Out of Galaxy Inc., Wilmington, Delaware) and the Thermos^® Smart Lid (Thermos LLC, Schaumburg, Illinois). In comparison testing, the HidrateSpark and H2OPal had the best accuracy.⁶ The Prevention of Urinary Stones with Hydration (PUSH) trial is an ongoing study that utilizes wireless-enabled smart water bottles to monitor daily fluid intake and to provide reminders, weekly summary of intakes, as well as financial incentives to participants.⁷ The study will be looking at the effect of these interventions on the progression of stone disease.

Technologies to Improve Adherence to Dietary and Medication Recommendations

In addition to increased fluid intake, dietary changes and medication are important to decrease recurrent stone events. There are currently more than one hundred diet-related applications on the market. The most popular is MyMyFitnessPal™ (MyFitnessPal Inc, San Francisco, California), which has a large database of foods and their associated calories and other nutrients. For kidney stone patients, these apps allow for careful tracking of calories, sodium and calcium intakes (see Table). Even as early as 2013, a review identified 44 apps specific to urolithiasis. Only 2 of these apps provided a way of recording daily calcium intake, and 6 provided dietary advice.⁸ While these particular apps have not been validated for clinical effectiveness, Lange and colleagues demonstrated that an Internet program that provides dietary advice and allows users to log daily food intake with immediate feedback on compliance led to significantly reduced oxalate excretion on 24-hour urine analyses.⁹

Adherence to medical therapy recommendations among kidney stone patients is associated with decreased odds of future stone events but is low at around 50%.¹⁰ Mobile applications that provide medication reminders may prove to be beneficial in stone formers. The most popular of these is Medisafe (MediSafe Inc., Boston, Massachusetts). With millions of users, it offers the ability to schedule medications, provide reminders, share data with family and physicians, and assess adherence. It is important to note that there are no studies currently validating these applications for the efficacy of kidney stone prevention or medication adherence.

Conclusion

The rapidly growing field of mobile health and smart technology has many applications in helping patients prevent the recurrence of stone disease. These include software applications to improve fluid intake, diet and medication adherence. Additionally, the integration of hardware technologies such as smart water bottles and wearables can further improve the ability to provide timely and effective reminders. As we are surrounded by more smart devices, the future of this technology relies on integration between the phone, the wearables, the water bottles and the physician’s office.

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Khambati A, Matulewicz RS, Perry KT et al: Factors associated with compliance to increased fluid intake and urine volume following dietary counseling in first-time kidney stone patients. J Endourol 2017; 31: 605.
Chua TXW, Prasad NS, Rangan GK et al: A systematic review to determine the most effective interventions to increase water intake. Nephrol Carlton Vic 2016; 21: 860.
Winoker JS, Koo K, Huang MM et al: Systematic evaluation of smartphone applications for the medical management of nephrolithiasis. J Endourol 2021; 35: 1058.
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