Effect of a DASH-Style Diet on Urinary Risk Factors for Kidney Stone Disease

Effect of a DASH-Style Diet on Urinary Risk Factors for Kidney Stone Disease: A Randomized Controlled Trial (CARDIA Ancillary Study)

The true capacity for a healthy diet to improve urinary stone risk factors is not well-defined. The objective of this study is to measure the effect of adopting a healthy dietary pattern on kidney stone disease (KSD) risk. The working hypothesis is that a Dietary Approaches to Stop Hypertension (DASH)-style diet will improve 24-hour urine stone risk parameters. The approach to testing this hypothesis will be to randomize participants with KSD to a standardized DASH-style vs. Western-style diet for one week. The Bionutrition Unit of the Center for Clinical and Translational Science will provide all meals to participants. The rationale for this study is that by measuring the effect of a DASH-style diet on urinary stone risk parameters, a benchmark for future real-world, implementation studies will be established. Based on available evidence, this will be the first controlled diet study to assess the DASH dietary pattern for improving urinary stone risk parameters.

Study Overview

• Status: Recruiting
• Conditions: Kidney Stone
• Intervention / Treatment: Other: DASH-Style Diet; Other: Western-Style Diet

• Study Type: Interventional
• Enrollment (Estimated): 48
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Joseph Crivelli, MD; Phone Number: 205-996-8765; Email: crivelli@uab.edu

Study Locations

• United States
  • Alabama
    • Birmingham, Alabama, United States, 35294
      • Recruiting
      • University of Alabama at Birmingham
      • Contact: Joseph Crivelli, MD; Phone Number: 205-996-8765; Email: crivelli@uab.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Birmingham, AL area participants of the Coronary Artery Risk Development in Young Adults (CARDIA) study OR patients of the University of Alabama at Birmingham/Kirklin Clinic
• Self-reported, documented, and/or prior imaging-based diagnosis of kidney stone disease
• Age 19-89
• Any sex
• Any race
• Able to provide informed consent
• Willing to perform 24-hour urine collections
• Willing to consume meals prepared by Bionutrition Unit
• No food allergies/intolerance to any of the foods in the study menus
• Willing to stop for 7 days before and during study: Multivitamins and/or Dietary supplements (including calcium and vitamin C)

Exclusion Criteria:

• Dialysis
• Kidney transplant recipient
• Estimated glomerular filtration rate (eGFR) <60 ml/min/1.73m2 based on historical laboratory measurements
• Renal tubular acidosis
• Current use of acetazolamide, topiramate, or zonisamide
• Primary hyperparathyroidism or history of parathyroidectomy
• Hyperthyroidism
• Sarcoidosis
• Primary hyperoxaluria
• Cystinuria
• Nephrotic syndrome
• Malabsorptive conditions including inflammatory bowel disease or history of malabsorptive surgery (e.g., Roux-en-Y gastric bypass, small bowel resection)
• Urinary retention requiring catheterization
• Urinary diversion
• Pregnancy
• Breastfeeding
• Malignancy treated in the past 12 months other than non-melanoma skin cancer

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: DASH-Style Diet; For seven days, participants will consume a diet characterized by higher intake of fruits, vegetables, and low-fat dairy, in addition to whole grains, poultry, fish, and nuts, but smaller amounts of red meat, sweets, and sugar-containing beverages.	Other: DASH-Style Diet; Participants will be randomized to a DASH-style diet
Other: Western-Style Diet; For seven days, participants will consume a diet characterized by characterized by higher intake of red meat, sweets, and items containing added sugar, processed starches, and seed oils, in addition to lower intake of fruits, vegetables, and low-fat dairy.	Other: Western-Style Diet; Participants will be randomized to a Western-style diet

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference between the two arms in supersaturation of calcium oxalate	Supersaturation of calcium oxalate is an index reflecting the propensity for the formation and growth of the most common stone type (calcium oxalate), which is calculated using excretion rates including urinary volume, calcium, citrate, and oxalate.	Days 6-7 of the assigned intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference between the two arms in supersaturation of calcium oxalate between the baseline and intervention periods	This secondary outcome will be calculated using a difference in differences approach.	Days 6-7 of the assigned intervention
Difference between the two arms in supersaturation of uric acid	Supersaturation of uric acid is an index reflecting the propensity for the formation and growth of uric acid stones.	Days 6-7 of the assigned intervention
Difference between the two arms in supersaturation of calcium phosphate	Supersaturation of calcium phosphate is an index reflecting the propensity for the formation and growth of calcium phosphate stones.	Days 6-7 of the assigned intervention
Difference between the two arms in urine volume	Low urine volume is a stone risk factor.	Days 6-7 of the assigned intervention
Difference between the two arms in urine calcium	High urine calcium is a stone risk factor.	Days 6-7 of the assigned intervention
Difference between the two arms in urine oxalate	High urine oxalate is a stone risk factor.	Days 6-7 of the assigned intervention
Difference between the two arms in urine citrate	Low urine citrate is a stone risk factor.	Days 6-7 of the assigned intervention
Difference between the two arms in urine uric acid	High urine uric acid is a stone risk factor.	Days 6-7 of the assigned intervention
Difference between the two arms in urine pH	Urine pH can influence stone formation and growth.	Days 6-7 of the assigned intervention

Collaborators and Investigators

• Sponsor: University of Alabama at Birmingham

Study record dates

Study Major Dates

• Study Start (Actual): January 6, 2025
• Primary Completion (Estimated): August 31, 2027
• Study Completion (Estimated): August 31, 2027

Study Registration Dates

• First Submitted: January 4, 2024
• First Submitted That Met QC Criteria: January 13, 2024
• First Posted (Actual): January 18, 2024

Study Record Updates

• Last Update Posted (Actual): January 13, 2026
• Last Update Submitted That Met QC Criteria: January 12, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Western diet; DASH diet
• Additional Relevant MeSH Terms: Urogenital Diseases; Male Urogenital Diseases; Calculi; Pathological Conditions, Anatomical; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urolithiasis; Urinary Calculi; Nephrolithiasis; Pathological Conditions, Signs and Symptoms; Kidney Calculi
• Other Study ID Numbers: IRB-300012217

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No