Long-Term Risk of Kidney Stones in Living Kidney Donors

NCT07611500 | Completed

• 1 other identifier: 2026 0906 443 007b
• Study Type: observational
• Target: 50,000
• Locations: 0 countries
• Sites: N/A

Brief Summary

Using a population-based, matched, retrospective cohort approach, this study will evaluate the long-term risk of kidney stones among living kidney donors compared with matched healthy nondonors. Linked administrative health care databases from Ontario, Alberta, and British Columbia will be used and living kidney donors who donated between 1992 and 2024 will be identified and matched 1:10 to a carefully selected population of healthy nondonors based on baseline characteristics. The primary outcome is a surgical intervention for kidney stones (including shockwave lithotripsy, ureteroscopy or percutaneous nephrolithotomy). The secondary outcome is a hospital encounter with a kidney stone diagnosis.

Conditions

Kidney Stones, Urolithiasis, Hypocitraturia; Living Kidney Donation; Living Kidney Donor

Keywords

Kidney stones; Living kidney donation

Outcome Measures

Primary Outcomes (1)

• Surgical intervention for kidney stones

  The first occurrence of a hospital admission for a surgical kidney stone procedure, including shockwave lithotripsy, ureteroscopy, or percutaneous nephrolithotomy, as recorded in provincial health administrative databases.

  Donors and matched nondonors will enter the cohort between July 1, 1992, and March 31, 2024, and will be followed until study outcome (first event), death, emigration from the province, or the end of the observation period (March 31, 2025).

Secondary Outcomes (1)

• Hospital encounter for kidney stones

  Donors and matched nondonors will enter the cohort between July 1, 1992 and March 31, 2024, and will be followed until study outcome (first event), death, emigration from the province, or the end of the observation period (March 31, 2025).

Study Arms (2)

Living kidney donor cohort

Living kidney donors who had a donor nephrectomy between July 1, 1992 and March 31, 2024, at transplant centres in the provinces of Ontario, Alberta, and British Columbia. Each nephrectomy date will serve as the cohort entry date.

Procedure: Living kidney donation

Healthy non-donor cohort

A similarly healthy segment of the general provincial population was selected using restriction and matching to emulate the health criteria required for living kidney donation. A cohort entry date (simulated nephrectomy date) will be randomly assigned to all residents in the province, according to the distribution of cohort entry dates in the donor cohort (between July 1, 1992 and March 31, 2024).

Interventions

Living kidney donation PROCEDURE

Nephrectomy for living kidney donation

Living kidney donor cohort

Eligibility Criteria

• Age: 18 Years - 105 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Living kidney donors matched to nondonors from the general population with similar indicators of baseline health.

You may not qualify if:

• Any person with data errors in their database records (such as missing or invalid age; it is expected to exclude very few persons for these reasons). Data errors also include evidence of prior dialysis or a prior solid organ transplant, as such individuals are not eligible to become donors.
• Any person who was not a permanent resident of the province (i.e., the patient lives outside of the province, and only came to the province to donate a kidney to the intended recipient). This will include anyone who is not eligible for the province's health insurance plan, anyone whose last contact date in the databases is less than 1 year after the cohort entry date, and anyone without a physician visit in the year following the nephrectomy hospital discharge.
• Any person who is \<18 years of age on the date of nephrectomy (as only under exceptional circumstances should a person less than 18 be approved for living donation).
• Any person with a history of kidney stones.
• \*Non-donors\*
• Any person with data errors in their database records (such as missing or invalid age).
• Any person who was not a permanent resident of the province. This will include anyone who is not eligible for the province's health insurance plan and anyone whose last contact date in the databases is less than 1 year after the cohort entry date.
• Any person who is \<18 years of age on the cohort entry date.
• Anyone who is pregnant at the time of the cohort entry date.
• Baseline illnesses and measures of health care access from historic records preceding the cohort entry date will be identified. The sample of eligible nondonors will be restricted to persons without a recorded medical condition that could preclude donation. Such recorded medical conditions will include a hospitalization for mental illness in the prior year; an intensive care unit admission in the prior year; a hospitalization for palliative care services in the prior year; multiple hospital admissions in the prior year; high comorbidity (as assessed by the Charlson comorbidity index and adjusted clinical group scores, where data are available); receipt of home oxygen therapy; residence at a long-term care facility; dementia; any record of prior nephrology consultation or kidney disease (including receipt of dialysis, a kidney biopsy, or a kidney procedure such as a partial or complete nephrectomy); previous solid organ transplant; disorders of the kidneys, ureters, or bladder; any record of cardiovascular disease (congestive heart failure, cardiovascular procedures, myocardial infarction, peripheral vascular disease, abdominal aortic aneurysm repair, ischemic stroke); hypertension in individuals \<50 years of age (persons with this condition are not accepted as donors in Canada); any record of obstructive sleep apnea; any cancer diagnosis; any liver disease or cirrhosis; diabetes; any serious infection (hepatitis, HIV, infective endocarditis); any record of autoimmune rheumatic conditions (such as rheumatoid arthritis or systemic lupus erythematosus); and any record of alcoholism.
• To ensure the nondonors have access to health care services from physicians, nondonors who had no evidence of a family physician visit in the 2 years prior to cohort entry will be excluded. Additionally, nondonors with more than 5 family physician visits in the 2 years prior to cohort entry will be excluded, as this could suggest an active health issue that needs attention before donation could occur.
• Any person with a history of kidney stones.

Sponsors & Collaborators

• London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's: lead

Related Publications (1)

• Thomas SM, Lam NN, Welk BK, Nguan C, Huang A, Nash DM, Prasad GV, Knoll GA, Koval JJ, Lentine KL, Kim SJ, Lok CE, Garg AX; Donor Nephrectomy Outcomes Research (DONOR) Network. Risk of kidney stones with surgical intervention in living kidney donors. Am J Transplant. 2013 Nov;13(11):2935-44. doi: 10.1111/ajt.12446. Epub 2013 Sep 18.

  PMID: 24102981 BACKGROUND

MeSH Terms

Conditions

Kidney Calculi; Urolithiasis

Condition Hierarchy (Ancestors)

Nephrolithiasis; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Urinary Calculi; Male Urogenital Diseases; Calculi; Pathological Conditions, Anatomical; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 21, 2026
• First Posted: May 28, 2026
• Study Start: July 1, 1992
• Primary Completion: March 31, 2024
• Study Completion: March 31, 2025
• Last Updated: May 28, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share