@article{e2126f4651d14df1bcd2ab7344fbf5ed,
title = "Application of the International IgA Nephropathy Prediction Tool one or two years post-biopsy",
abstract = "The International IgA Nephropathy (IgAN) Prediction Tool is the preferred method in the 2021 KDIGO guidelines to predict, at the time of kidney biopsy, the risk of a 50% drop in estimated glomerular filtration rate or kidney failure. However, it is not known if the Prediction Tool can be accurately applied after a period of observation post-biopsy. Using an international multi-ethnic derivation cohort of 2,507 adults with IgAN, we updated the Prediction Tool for use one year after biopsy, and externally validated this in a cohort of 722 adults. The original Prediction Tool applied at one-year without modification had a coefficient of variation (R2) of 55% and 54% and four-year concordance (C statistic) of 0.82 but poor calibration with under-prediction of risk (integrated calibration index (ICI) 1.54 and 2.11, with and without race, respectively). Our updated Prediction Tool had a better model fit with higher R2 (61% and 60%), significant increase in four-year C-statistic (0.87 and 0.86) and better four-year calibration with lower ICI (0.75 and 0.35). On external validation, the updated Prediction Tool had similar R2 (60% and 58%) and four-year C-statistics (both 0.85) compared to the derivation analysis, with excellent four-year calibration (ICI 0.62 and 0.56). This updated Prediction Tool had similar prediction performance when used two years after biopsy. Thus, the original Prediction Tool should be used only at the time of biopsy whereas our updated Prediction Tool can be used for risk stratification one or two years post-biopsy.",
keywords = "IgA nephropathy, disease progression, end-stage kidney disease, prediction tool, risk prediction",
author = "Barbour, {Sean J.} and Rosanna Coppo and Hong Zhang and Zhi-Hong Liu and Yusuke Suzuki and Keiichi Matsuzaki and Lee Er and Reich, {Heather N.} and Jonathan Barratt and Cattran, {Daniel C.} and {International IgA Nephropathy Network} and Russo, {M. L.} and S. Troyanov and Cook, {H. T.} and I. Roberts and V. Tesar and D. Maixnerova and S. Lundberg and L. Gesualdo and F. Emma and L. Fuiano and G. Beltrame and C. Rollino and A. Amore and R. Camilla and L. Peruzzi and M. Praga and S. Feriozzi and R. Polci and G. Segoloni and L. Colla and A. Pani and D. Piras and A. Angioi and G. Cancarini and S. Ravera and M. Durlik and E. Moggia and J. Ballarin and {di Giulio}, S. and F. Pugliese and I. Serriello and Y. Caliskan and M. Sever and I. Kilicaslan and F. Locatelli and {del Vecchio}, L. and S. Florquin and Z. Liu and J. Weening and K. Takahashi",
note = "Funding Information: Funding support for this project was provided by grant funding from the Canadian Institutes of Health Research (PCG-155557). The European Validation Study of the Oxford Classification of IGA Nephropathy (VALIGA) study was supported by a grant from the first research call and the Immunonephrology Working Group of the European Renal Association – European Dialysis and Transplant Association. The Oxford derivation and North American Validation studies were supported by the International IgA Nephropathy Network, the Toronto GN Registry, and the Toronto General Hospital Foundation (McCann Fund). The funders had no role in the design or conduct of the study; the collection, management, analysis, or interpretation of the data; the preparation, review, or approval of the manuscript; or the decision to submit the manuscript for publication. Publisher Copyright: {\textcopyright} 2022 International Society of Nephrology",
year = "2022",
month = jul,
day = "1",
doi = "https://doi.org/10.1016/j.kint.2022.02.042",
language = "English",
volume = "102",
pages = "160--172",
journal = "Kidney International",
issn = "0085-2538",
publisher = "Nature Publishing Group",
number = "1",
}