Obesity and Endogenous Oxalate Synthesis

NCT ID: NCT03808090

Last Updated: 2024-09-19

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 58 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2013-01-01
• Study Completion Date: 2024-07-31

Brief Summary

The goal of this study is to determine if obesity is associated with increased endogenous oxalate synthesis as assessed by urinary oxalate excretion, which is a known risk factor for calcium oxalate kidney stones.

The study will recruit adult participants without history of kidney stones. Participants will

• Ingest fixed diets containing low amounts of oxalate for 4 days
• Collect 24-hr urine samples during the fixed diet

Detailed Description

In this study the investigators propose to measure the excretion of urinary oxalate on a fixed diet with controlled amounts of oxalate, in individuals of varying body sizes without history of kidney stones. The 24-hr urinary oxalate excretion on such a low-oxalate normal calcium fixed diet is determined to be an appropriate surrogate for endogenous oxalate synthesis.

Screening phase. The study will enroll 60 individuals without history of kidney stones (30 males/30 females) at the University of Alabama at Birmingham (UAB).

Screening will include blood complete metabolic profile, 24-hr urine specimens collected at home on self-selected diets and anthropometric measurements.

Dietary phase Participants will ingest a low-oxalate (<60 mg/day), normal calcium (1000 mg/day) fixed diet for 4 consecutive days, collect three 24-hr urines after 1 day of dietary equilibration and have a fasted blood draw on day 5.

Conditions

Obesity

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Normal Individuals

Normal individuals: no prior history of kidney stones

Group Type: EXPERIMENTAL

Normal Individuals

Intervention Type: DIETARY_SUPPLEMENT

Controlled Dietary phase: Low oxalate fixed diet

4 days of fixed normal calorie diet with low oxalate (< 60 mg/day), normal calcium (800-1200 mg/day)

Interventions

Normal Individuals

Controlled Dietary phase: Low oxalate fixed diet

4 days of fixed normal calorie diet with low oxalate (< 60 mg/day), normal calcium (800-1200 mg/day)

Intervention Type: DIETARY_SUPPLEMENT

Eligibility Criteria

Inclusion Criteria

Age 19-70 yrs Body Mass Index > 18.5 kg/m2 Normal fasting serum electrolytes on comprehensive metabolic profile Willing to ingest fixed diets

Exclusion Criteria

Chronic Kidney Disease, estimated glomerular filtration rate < 60 ml/mn/1.73m2 Primary hyperoxaluria Liver, endocrine or renal diseases or any other condition that may influence the absorption, transport or urinary excretion of ions, which will compromise the interpretation of results, including: Cystic fibrosis, Cystinuria, Uric acid stone former, Nephrotic syndrome, Sarcoidosis, Renal tubular acidosis, Primary hyperparathyroidism, Neurogenic bladder, Urinary diversion Pregnancy or breast-feeding Incompatible dietary requirements with the study, food allergies or intolerance to any of the foods in study menus Active malignancy or treatment for malignancy within 12 months prior to screening Utilization of immunosuppressive medication Uncontrolled Hypertension or diabetes

• Minimum Eligible Age: 19 Years
• Maximum Eligible Age: 70 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National Institutes of Health (NIH)

NIH

Sponsor Role: collaborator

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

NIH

Sponsor Role: collaborator

University of Alabama at Birmingham

OTHER

Sponsor Role: lead

Responsible Party

Kyle D. Wood

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Kyle D Wood, MD

Role: PRINCIPAL_INVESTIGATOR

University of Alabama at Birmingham

Locations

University of Alabama at Birmingham

Birmingham, Alabama, United States

Countries

United States

Provided Documents

Document Type: Study Protocol and Statistical Analysis Plan

View Document

Document Type: Informed Consent Form

View Document

Other Identifiers

1K08DK115833-01A1

Identifier Type: NIH

Identifier Source: secondary_id

View Link

IRB130502007-OBE

Identifier Type: -

Identifier Source: org_study_id