{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T16:20:04Z","timestamp":1778775604585,"version":"3.51.4"},"reference-count":27,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,9,26]],"date-time":"2022-09-26T00:00:00Z","timestamp":1664150400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002848","name":"ANID PIA\/APOYO","doi-asserted-by":"publisher","award":["AFB180003"],"award-info":[{"award-number":["AFB180003"]}],"id":[{"id":"10.13039\/501100002848","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002848","name":"ANID PIA\/APOYO","doi-asserted-by":"publisher","award":["ID19I10303"],"award-info":[{"award-number":["ID19I10303"]}],"id":[{"id":"10.13039\/501100002848","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Fondo Nacional de Investigaci\u00f3n y Desarrollo","award":["AFB180003"],"award-info":[{"award-number":["AFB180003"]}]},{"name":"Fondo Nacional de Investigaci\u00f3n y Desarrollo","award":["ID19I10303"],"award-info":[{"award-number":["ID19I10303"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: We developed a predictive statistical model to identify donor\u2013recipient characteristics related to kidney graft survival in the Chilean population. Given the large number of potential predictors relative to the sample size, we implemented an automated variable selection mechanism that could be revised in future studies as more national data is collected. Materials and Methods: A retrospective multicenter study was conducted to analyze data from 822 adult kidney transplant recipients from adult donors between 1998 and 2018. To the best of our knowledge, this is the largest kidney transplant database to date in Chile. A procedure based on a cross-validated regularized Cox regression using the Elastic Net penalty was applied to objectively identify predictors of death-censored graft failure. Hazard ratios were estimated by adjusting a multivariate Cox regression with the selected predictors. Results: Seven variables were associated with the risk of death-censored graft failure; four from the donor: age (HR = 1.02, 95% CI: 1.00\u20131.03), male sex (HR = 0.64, 95% CI: 0.46\u20130.90), history of hypertension (HR = 1.49, 95% CI: 0.98\u20132.28), and history of diabetes (HR = 2.04, 95% CI: 0.97\u20134.29); two from the recipient: years on dialysis log-transformation (HR = 1.29, 95% CI: 0.99\u20131.67) and history of previous solid organ transplantation (HR = 2.02, 95% CI: 1.18\u20133.47); and one from the transplant: number of HLA mismatches (HR = 1.13, 95% CI: 0.99\u20131.28). Only the latter is considered for patient prioritization in deceased kidney allocation in Chile. Conclusions: A risk model for kidney graft failure was developed and trained for the Chilean population, providing objective criteria which can be used to improve efficiency in deceased kidney allocation.<\/jats:p>","DOI":"10.3390\/medicina58101348","type":"journal-article","created":{"date-parts":[[2022,9,26]],"date-time":"2022-09-26T05:20:58Z","timestamp":1664169658000},"page":"1348","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Identifying Factors Predicting Kidney Graft Survival in Chile Using Elastic-Net-Regularized Cox\u2019s Regression"],"prefix":"10.3390","volume":"58","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6029-1247","authenticated-orcid":false,"given":"Leandro","family":"Magga","sequence":"first","affiliation":[{"name":"Department of Industrial Engineering, University of Chile, Santiago 8370456, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sim\u00f3n","family":"Maturana","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, University of Chile, Santiago 8370456, Chile"},{"name":"Instituto Sistemas Complejos de Ingenier\u00eda, Santiago 8370398, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8465-624X","authenticated-orcid":false,"given":"Marcelo","family":"Olivares","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, University of Chile, Santiago 8370456, Chile"},{"name":"Instituto Sistemas Complejos de Ingenier\u00eda, Santiago 8370398, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mart\u00edn","family":"Valdevenito","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, University of Chile, Santiago 8370456, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Josefa","family":"Cabezas","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, University of Chile, Santiago 8370456, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Javier","family":"Chapochnick","sequence":"additional","affiliation":[{"name":"Cl\u00ednica Santa Mar\u00eda, Santiago 7520378, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fernando","family":"Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Hospital del Salvador, Santiago 7500922, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alvaro","family":"Kompatzki","sequence":"additional","affiliation":[{"name":"Hospital S\u00f3tero del R\u00edo, Santiago 8207257, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hans","family":"M\u00fcller","sequence":"additional","affiliation":[{"name":"Hospital Las Higueras, Talcahuano 4270918, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jacqueline","family":"Pefaur","sequence":"additional","affiliation":[{"name":"Hospital Barros Luco Trudeau, Santiago 8900085, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Camilo","family":"Ulloa","sequence":"additional","affiliation":[{"name":"Cl\u00ednica Alemana de Santiago, Santiago 8320000, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5522-7670","authenticated-orcid":false,"given":"Ricardo","family":"Valjalo","sequence":"additional","affiliation":[{"name":"Hospital del Salvador, Santiago 7500922, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Mark, E., Goldsman, D., Gurbaxani, B., Keskinocak, P., and Sokol, J. 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