Effectiveness of Urinary Alkalinizing Agents on Kidney Stone Risk

Effectiveness of Prescription vs. Non-prescription Urinary Alkalinizing Agents on Kidney Stone Risk

Randomized treatment trial of baking soda or LithoLyte to determine if baking soda and Litholyte are effective in raising 24 hour urine citrate and pH.

Study Overview

• Status: Completed
• Conditions: Kidney Stone
• Intervention / Treatment: Dietary supplement: Baking Soda; Dietary supplement: LithoLyte

Detailed Description

Participants will not be required to attend any study visits outside of normal clinical encounters. Participants enrolled in the study will be randomized to treatment upon enrollment. Blocked randomization will be conducted, utilizing sex (M/F) and recurrent stone former (Y/N) as algorithm variables.

Participants randomized to LithoLyte® will be provided 40 mEq of alkali in the form of LithoLyte® and advised to take 20 mEq twice daily according to package instructions, once in morning and once at bedtime; no requirements about proximity to meals are necessary.

Participants randomized to baking soda will be provided instructions for using baking soda to provide 40 mEq alkali, to be accomplished by dissolving ¼ teaspoon baking soda in water or other beverage (any amount) in the morning on an empty stomach and ½ teaspoon baking soda in water or other beverage again at bedtime, also on an empty stomach.

The 24-hour urine results that are available upon enrollment will be used for pre-intervention values. The 24-hour results from each participant's followup collection will be used for post-intervention values. Thus, no extra encounters are required for participation in the study. Additionally, no extra tests are required for participation in the study as participants would normally complete a post-treatment 24-hour urine collection anyway. Participants will be screened for eligibility, i.e., by pre-clinic review of schedules and 24-hour urine results. Only those meeting inclusion criteria will be invited to participate and enrolled, provided that informed consent is provided by signing the signature page of the consent/authorization form. The treatment/intervention period is up to 90 days (approximately 3 months). However, it should be noted that, as these are clinical interventions that would be prescribed or recommended anyway, it is expected that participants will continue treatment indefinitely and under supervision of urology and/or Metabolic Stone Clinic providers. If the participant has failed the randomized therapy they are assigned to, they will be clinically assigned a different treatment option and continue to be followed up in routine fashion.

Participants will also be asked to complete a medication questionnaire and log, as well as the Wisconsin Stone Quality of Life (WISQOL) questionnaire. All study procedures are considered standard of care, except for: randomization into treatment and the medication questionnaire and log.

Protocol Amendment Approved 11/16/2020 removed the UrocitK study arm; the investigators faced challenges recruiting participants during the COVID-19 pandemic and the possibility of being randomized into a prescription drug arm was causing many potential participants to choose not to participate.

• Study Type: Interventional
• Enrollment (Actual): 31
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • Wisconsin
    • Madison, Wisconsin, United States, 53726
      • UW-Madison

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Must be suitable for the study per clinical judgement of study team members
• Patient in the UW Health University Hospital Urology Clinic or the Metabolic Stone Clinic
• Had at least one kidney stone event
• Greater than or equal to 18 years of age
• 24 hour urine citrate is less than 420 mg and/or urine pH is less than 5.9
• Urinary alkalinization is deemed by provider as a necessary therapeutic goal for the subject and may be achieved by any of the three therapies under examination
• Subject is willing to provide consent and to be randomized into a treatment

Exclusion Criteria:

• Subject is deemed unsuitable for urinary alkalinizing therapy by study staff
• Subject is already on a urinary alkalinizing agent
• Subject is on acetazolamide
• Subject reports sensitivity to sugar alcohols
• Subject is under 18 years of age
• Subject has not completed a 24 hour urine collection within 6 months
• Subject is pregnant or breastfeeding
• Subject is unable or unwilling to provide consent
• Subject is unable or unwilling to be randomized
• Subject reports they are unwilling or unable to use measuring device required in the baking soda arm of the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Baking Soda; Subjects randomized to baking soda will be provided instructions for using baking soda to provide 40 mEq alkali, to be accomplished by dissolving ¼ teaspoon baking soda in water or other beverage (any amount) in the morning on an empty stomach and ½ teaspoon baking soda in water or other beverage again at bedtime, also on an empty stomach.	Dietary supplement: Baking Soda; Standard baking soda that can be bought from stores.
Active Comparator: LithoLyte; Subjects randomized to LithoLyte® will be provided 40 mEq of alkali in the form of LithoLyte® and advised to take 20 mEq twice daily according to package instructions, once in morning and once at bedtime; no requirements about proximity to meals are necessary.	Dietary supplement: LithoLyte; LithoLyte is considered a medical food and consists of: potassium citrate, magnesium citrate, sodium bicarbonate, and erythritol.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in 24 hour urine citrate	Pre-to-post intervention change in 24-hour urine citrate will be measured Reference range of Urine Citrate: 18 years and older: 320-1240 mg/d 1 year and older: greater than or equal to 150 mg/g.	Pre and 24 hour post intervention (up to 90 days)
Change in 24 hour urine pH	Pre-to-post intervention change in 24-hour urine pH will be measured Reference range of Urine pH: Age 0 days and up: 5.0-8.0	Pre and 24 hour post intervention (up to 90 days)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Post-intervention 24-hour urine calcium	Urine calcium levels will be measured post intervention. Reference range of Urine Calcium: 0-17 years: up to 6.0 mg/kg/24 hours 18 years and up: 100-300 mg/24 hours	Enrollment and follow up visit (approximately 90 days)
24 hour urine calcium	Reference range of urine calcium: 0-12 years: 7-31 mg/d Male 13 years and older: 16-49 mg/d Female 13 years and older: 13-40 mg/d	Enrollment and follow up visit (approximately 90 days)
Post interventional 24 hour urine supersaturation indices for calcium oxalate	Supersaturation means there are too many salts and not enough fluids in the urine. It's the driving force behind stone formation. Post interventional 24 hour urine supersaturation indices for calcium oxalate will be measured. Reference range: 0-12 years: 7-31 mg/d Male 13 years and older: 16-49 mg/d Female 13 years and older: 13-40 mg/d	Enrollment and follow up visit (approximately 90 days)
Post interventional 24 hour urine supersaturation indices for calcium phosphatase	Supersaturation means there are too many salts and not enough fluids in the urine. It's the driving force behind stone formation. Post interventional 24 hour urine supersaturation indices for calcium phosphatase will be measured. Reference range: Age 18 years and up: 0.4-1.3 g/24 hour	Enrollment and follow up visit (approximately 90 days)
Cost of Treatment as measured by USD spent on the interventional drug	Cost of baking soda versus LithoLyte.	End of study (approximately 90 days)
Patient acceptability	Wisconsin Stone-QOL: answers range from a scale of 1-5, or yes/no Study Questionnaire: free text responses, or no/yes/I am no longer taking it	End of study (approximately 90 days)

Collaborators and Investigators

• Sponsor: University of Wisconsin, Madison
• Investigators: Principal Investigator: Kristina L Penniston, PhD, RDN, FAND, University of Wisconsin, Madison

Study record dates

Study Major Dates

• Study Start (Actual): August 28, 2019
• Primary Completion (Actual): June 24, 2021
• Study Completion (Actual): June 24, 2021

Study Registration Dates

• First Submitted: September 17, 2019
• First Submitted That Met QC Criteria: September 17, 2019
• First Posted (Actual): September 19, 2019

Study Record Updates

• Last Update Posted (Actual): November 22, 2021
• Last Update Submitted That Met QC Criteria: November 12, 2021
• Last Verified: November 1, 2021

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Kidney Diseases; Urologic Diseases; Pathological Conditions, Anatomical; Urolithiasis; Urinary Calculi; Calculi; Kidney Calculi; Nephrolithiasis
• Other Study ID Numbers: 2019-0621; A539800 (Other Identifier: UW Madison); SMPH/UROLOGY/UROLOGY (Other Identifier: UW Madison); Protocol Version 9/9/2020 (Other Identifier: UW Madison)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No