A Dietary Source of Potassium Citrate to Resolve Hypocitraturia and Aciduria in Patients With Kidney Stones

Kidney Calculi Clinical Trial

Official title:

A Dietary Source of Potassium Citrate to Resolve Hypocitraturia and Aciduria in Patients With a History of Nephrolithiasis

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03984409
• Other study ID #: 1903221743
• Status: Completed
• Phase: N/A
• Start date: June 1, 2019
• Est. completion date: November 1, 2020

Study information

• Verified date: November 2020
• Source: Indiana University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Patients with nephrolithiasis and evidence of hypocitraturia or aciduria who would otherwise be started on potassium citrate, can achieve similar urine alkalization with 500-1000 mL of daily low calorie orange juice consumption.

Description:

Potassium Citrate (kcit) has long been utilized by physicians to combat stone formation in patients with hypocitraturia or aciduria. The most common obstacle to patient compliance with this medication has historically been dosing frequency, pill size, dyspepsia, and its familiar unpleasant taste. However, rampant increases in drug pricing by pharmaceutical companies, that have achieved market control of the drug supply, are triggering non-compliance in the subset of stone patients who depend on potassium citrate therapy to prevent stone recurrence.

Previous research has shown that certain commercially available beverages contain alkali citrate, of which orange juice (OJ) has the highest reported concentrations of potassium citrate based on ion chromatography. Unfortunately, the high sugar content of orange juice excludes its potential use as a dietary alternative to prescription potassium citrate. Recently, major beverage companies (Pepsi, Coca Cola) have release low calorie beverages with equivalent citrate content but with 50% less sugar. In early 2018 the investigaotrs performed ion-chromatography on various consumer beverages and validated that low calorie orange juice provided equivalent alkali citrate and malate to standard orange juice. The ion-chromatography also showed that the total amount of alkali/liter was greater in low calorie orange juice compared to crystal light lemon flavored. Currently, crystal light lemon is recommended as the next best option to water for recurrent stone formers with low urine volume production and hypocitraturia or aciduria (https://kidneystones.uchicago.edu/price-of-potassium-citrate/). However, there is a concern that the citrate within lemon based beverages is predominantly in an acidic form and thus has less potential to provide clinically affective levels of alkali despite a favorable alkali profile on ion chromatography.

Since low calorie orange juice was identified as a potential sources for citrate and alkali, the investigators wanted to show that consumption of the beverages resulted in desirable changes in urinary pH and citrate levels without negatively affecting patient well-being. Ten (10) volunteers drank standardized quantities of water, crystal light lemon juice, and two low calorie orange juices. After 7 days of beverage consumption the participants performed a 24 hour urine collection which was performed by an independent laboratory. The participants also maintained a diary of dietary (both food and drink) intake in addition to the trial beverages. The data from the study is very promising with desired changes in urinary pH and citrate levels with consumption of the low calorie orange juice. Minimal side effects were noted from consuming the low calorie orange juice except with Tropicana50 based on journals. It was determined that the artificial sweetener in TRP50 was the causative agent for GI symptoms and headaches. The preferred brand based on volunteer diaries was a generic brand by Kroger® low calorie orange beverage.

Our data suggests that low calorie orange juice has the potential to improve compliance rates with alkali therapy amongst recurrent stone formers. Stone prevention is key to reducing long-term sequelae of repeat surgical intervention such as iatrogenic genitourinary strictures, infections, and end organ damage. Additionally, there is a large cost savings potential with stone prevention by reducing hospital stays, surgical procedures, and missed work days due to stone disease. While daily low calorie orange juice may not completely supplant prescription potassium citrate therapy, it may be a favorable adjunct to reduce cost associated with potassium citrate and increase compliance rates by reducing the dose required to clinically relevant alkalization of the urine. Our hypothesis, is that patients with nephrolithiasis and evidence of hypocitraturia or aciduria who would otherwise be started on potassium citrate, can achieve similar urine alkalization with 500-1000 mL of daily low calorie orange juice consumption.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 22
• Est. completion date: November 1, 2020
• Est. primary completion date: August 31, 2020
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 75 Years

Eligibility

Inclusion Criteria:

• • Between 18 and 75 year of age.

• History of kidney stone disease with available stone analysis

• Evidence of aciduria or hypocitraturia on 24 hour urinalysis (24 hr citrate male <450 mg/day female <550 mg/day) or aciduria (urine pH < 5.8)

• Ability to drink Kroger low calorie orange juice beverage

• If subject with history of diabetes mellitus, must have HgA1c < 7.5 and willing to check daily blood sugars.

Exclusion Criteria:

• • Less than 18 or older than 75 years of age

• Allergies to low calorie orange juice, including intolerance because of side effects including (but not limited to): gastrointestinal symptoms, headaches, weight gain, unable to drink because of taste.

• Poorly controlled diabetic (HgA1c >7.5)

• No evidence of hypocitraturia or aciduria on 24 hour urinalysis

• Unable to afford potassium citrate therapy or tolerate medication because of side effects.

• Unwilling to perform 3 24-hour urine collections

Related Conditions & MeSH terms

• Calculi
• Kidney Calculi
• Nephrolithiasis

Intervention

Dietary Supplement:
• Kroger low calorie orange juice beverage
Kroger low calorie orange juice beverage will be consumed for 7 days followed by a 24 hour urine collection with Litholink to see if urine alkalization similar to potassium citrate can be achieved

Locations

Country	Name	City	State
United States	Indiana University Health Methodist Hospital	Indianapolis	Indiana
United States	Indiana University Health Physicians Urology	Indianapolis	Indiana

Sponsors (1)

Lead Sponsor	Collaborator
Indiana University

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Urine alkalization from Kroger low calorie orange juice beverage	The primary endpoint of interest will be the changes in urinary citrate while consuming Kroger low calorie orange juice beverage compared to potassium citrate therapy.	9 weeks from enrollment
Primary	Urine alkalization from Kroger low calorie orange juice beverage	The primary endpoint of interest will be the changes in urinary pH while consuming Kroger low calorie orange juice beverage compared to potassium citrate therapy.	9 weeks from enrollment