Kidney Week

Abstract: FR-PO0940

Association Between Vitamin D Supplementation and Relapses in Children with Nephrotic Syndrome: A Target Trial Emulation Study

Session Information

• Pediatric Nephrology: Genetic Diseases, Development, Neonatal Nephrology, Glomerular Diseases, and More
  October 23, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Pediatric Nephrology

• 1800 Pediatric Nephrology

Authors

• Robinson, Cal, The Hospital for Sick Children, Toronto, Ontario, Canada

Cal Robinson, MBChB, PhD, FASN

• Sivaratnam, Surabhi, The Hospital for Sick Children, Toronto, Ontario, Canada

Surabhi Sivaratnam, MD

• Aman, Nowrin F., The Hospital for Sick Children, Toronto, Ontario, Canada

Nowrin F. Aman, MBBS, MSc

• Banh, Tonny Hue Minh, The Hospital for Sick Children, Toronto, Ontario, Canada

Tonny Hue Minh Banh

• Brooke, Josefina A., The Hospital for Sick Children, Toronto, Ontario, Canada

Josefina A. Brooke, RN

• Bruno, Valentina, The Hospital for Sick Children, Toronto, Ontario, Canada

Valentina Bruno, MD, MS, MSc

• Dhillon, Vaneet, The Hospital for Sick Children, Toronto, Ontario, Canada

Vaneet Dhillon, NP, RN

• Garner, Mackenzie Alexander, The Hospital for Sick Children, Toronto, Ontario, Canada

Mackenzie Alexander Garner

• Licht, Christoph, The Hospital for Sick Children, Toronto, Ontario, Canada

Christoph Licht, MD, FASN

• McKay, Ashlene Maree, The Hospital for Sick Children, Toronto, Ontario, Canada

Ashlene Maree McKay, MD

• Noone, Damien Gerard, University of Alberta, Edmonton, Alberta, Canada

Damien Gerard Noone, MD, MSc

• Pearl, Rachel Jane, The Hospital for Sick Children, Toronto, Ontario, Canada

Rachel Jane Pearl, MD

• Radhakrishnan, Seetha, The Hospital for Sick Children, Toronto, Ontario, Canada

Seetha Radhakrishnan, MD

• Selvathesan, Nithiakishna, The Hospital for Sick Children, Toronto, Ontario, Canada

Nithiakishna Selvathesan, MD, MBChB

• Teoh, Chia Wei, The Hospital for Sick Children, Toronto, Ontario, Canada

Chia Wei Teoh, MBChB, MSc

• Vanos Hosick, Kristen, The Hospital for Sick Children, Toronto, Ontario, Canada

Kristen Vanos Hosick, RN

• Vasilevska-Ristovska, Jovanka, The Hospital for Sick Children, Toronto, Ontario, Canada

Jovanka Vasilevska-Ristovska, MD

• Parekh, Rulan S., Women's College Hospital, Toronto, Ontario, Canada

Rulan S. Parekh, MD, MS, FASN

Background

Nephrotic syndrome is a common childhood immune-mediated glomerular disease. More than half of children develop vitamin D deficiency. Vitamin D has immunomodulatory properties, which may influence nephrotic syndrome outcomes. Our objective was to determine if vitamin D supplementation lowers nephrotic syndrome relapse risk.

Methods

We emulated a hypothetical randomized controlled trial comparing vitamin D supplementation vs. usual care using observational data from a prospective cohort. We included children (6mo-18yr) with immunosuppression-responsive nephrotic syndrome. Vitamin D supplementation was reported at annual study visits. The primary outcome was relapse by the next study visit or end of follow-up. We used marginal structural models with propensity score overlap weighting and weighted logistic regression to evaluate the effect of vitamin D supplementation on relapse, accounting for time-varying exposures and confounders. Secondary outcomes (relapse rate, time-to-relapse, and initiation of steroid-sparing medication) were evaluated using marginal structural models with weighted regression.

Results

We included 745 children with nephrotic syndrome (6060 study visits). Median (IQR) follow-up was 5.2 (3.0-9.3) years. Vitamin D supplementation was being used at 1393 (23%) study visits, and 394 (53%) children ever used vitamin D. After propensity score overlap weighting, all covariates were balanced and propensity score distributions overlapped. Vitamin D supplementation was associated with a significantly lower risk of relapse (weighted OR 0.83, 95%CI 0.73-0.95, p=0.006) and steroid-sparing medication initiation (weighted OR 0.78, 95%CI 0.64-0.96), but no difference in relapse rate or time-to-relapse. Relapse risk decreased in a graded manner with higher vitamin D supplementation dose and serum vitamin D level.

Conclusion

Vitamin D supplementation is associated with a lower risk of childhood nephrotic syndrome relapses. Vitamin D is a safe, low-cost intervention with potential benefits in childhood nephrotic syndrome.

Outcomes among 745 children with nephrotic syndrome by vitamin D supplementation use

Funding

• Government Support – Non-U.S.