KIDMO—Kidney prediction model

Risk calculator for deceased-donor kidney transplantation in Switzerland.

Auteur·rice

Swisstransplant

Date de publication

7 août 2023

What is KIDMO?

KIDMO is a prediction tool that helps clinicians and patients to see how the combination of donor, transplant and recipient clinical characteristics can affect graft survival after deceased-donor kidney transplantation.

How was KIDMO developed?

KIDMO was developed by Swisstransplant—the national organisation for organ donation and transplantation in Switzerland and all the six transplant centers.

The model is based on follow-up data from the Swiss Transplant Cohort Study (STCS) and information from the Swiss Organ Allocation System (SOAS) from over 2,000 kidney recipients transplanted between 2008 and 2021.

What can KIDMO predict?

It is not possible to predict the exact time of organ loss in the future. However, based on all the high-quality data we collected in Switzerland, we can estimate the risk for kidney graft failure for a specific patient conditional on some clinical characteristics.

In the statistical model, the primary outcome was graft survival calculated from the date of of transplantation to the date of irreversible graft failure by return to dialysis (or retransplantation).

More details about KIDMO can be found in the published study protocol.

Terms of use

The KIDMO is currently under development and for FOR RESEARCH PURPOSES ONLY; the program must not be used in clinical practice.

The KIDMO risk calculator (hereinafter referred to as “program”) comes with ABSOLUTELY NO WARRANTY and LIMITATION OF LIABILITY. The program is currently under development and FOR RESEARCH PURPOSES ONLY; this program must not be used in clinical practice, including, but not limited to, clinical decision making. This program is provided WITHOUT ANY WARRANTY; without even the implied warranty of merchantability or fitness for a particular purpose. In no event unless required by applicable law will any copyright holder, or any other party who uses this program be liable for damages, including any general, special, incidental or consequential damages arising out of the use or inability to use this program.

Risk calculator

Interpretation

  • The HR (hazard ratio) shows the relative increase or decrease in the event rate of kidney graft failure for this recipient compared to the median event rate in the reference population. So, a HR > 1 indicates a higher hazard, and a HR < 1 indicated lower hazard and a more favorable outcome as what we observe in average. A recipient with a HR of 1.0 corresponds to the median hazard.

  • The rank is the percentile of the recipients’ calculated hazard ratio and is interpreted as the percentage of recipients in the reference population with lower or equal hazard compared to the new recipient. The rank has a range from 0% to 100%, and the lower the score, the more favorable the outcome.

  • The CI (cumulative incidence) is the probability of occurrence of kidney graft failure over time at 2, 5 and 10 years.

Example
  • A HR of 0.69 means that the recipient may have graft failure at about 0.7-fold the rate of a recipient with median hazard. In other words, there is a decrease of the hazard rate by about 30%.

  • A recipient’s rank of 36% indicates that 36% of recipients had a lower or equal hazard rate, and 64% had a higher hazard rate.

  • A 10-year CI of 0.04 indicated that the probability of kidney graft failure for this recipient is 4% over a period of 10 years after transplantation. In other words, 4 in 100 recipients with similar clinical characteristics may experience kidney graft failure after 10 years.

The hazard rate is the frequency with which a kidney transplant fails per unit of time. The reference population is all the kidney recipients transplanted between 2008 to 2021 at a Swiss transplant center and included in the study. The reference recipient is a recipient transplanted in 2015 with all the clinical predictor variables set to the reference levels (median donor age: 54, donor history of diabetes: no, etc.) The risk calculator is initially set to the reference values except the transplantation year is set to 2021.

References

Study protocol

Schwab, S., Sidler, D., Haidar, F., Kuhn, C., Schaub, S., Koller, M., Mellac, K., Stürzinger, U., Tischhauser, B., Binet, I., Golshayan, D., Müller, T., Elmer, A., Franscini, N., Krügel, N., Fehr, T., Immer, F., Swisstransplant Kidney Working Group (STAN), & Swiss Transplant Cohort Study. (2023). Clinical prediction model for prognosis in kidney transplant recipients (KIDMO): study protocol. Diagnostic and Prognostic Research, 7(1), 6. doi:10.1186/s41512-022-00139-5

Acknowledgements

KIDMO was developed by Swisstransplant and all the Swiss transplant centers. Kidney recipients have been involved in the development of KIDMO.