{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T21:07:58Z","timestamp":1774386478450,"version":"3.50.1"},"reference-count":27,"publisher":"Public Library of Science (PLoS)","issue":"3","license":[{"start":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T00:00:00Z","timestamp":1774310400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>This study assesses the impact of functional iron deficiency (FID) on outcomes, including all-cause mortality, hospitalizations and non-fatal cardiovascular events in patients with non-dialysis chronic kidney disease (CKD) and hemodialysis (HD).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In HD, absolute iron deficiency (AID) was defined as ferritin\u2009&lt;\u2009200 \u00b5g\/L and TSAT (transferrin saturation) \u2264 20%, and FID ferritin \u2265200 \u00b5g\/L with TSAT \u226420%. In CKD, AID was ferritin\u2009&lt;\u2009100 \u00b5g\/L and TSAT\u2009\u2264\u200920%, and FID ferritin\u2009\u2265\u2009100 \u00b5g\/L with TSAT\u2009\u2264\u200920%. Prevalent HD patients as of January 2012 and incident patients between January 2012 and December 2014 were included (n\u2009=\u2009512) and followed to 31\/12\/2018 (median 36.5 months). CKD patients who received iron infusions between January 2017 and December 2019 were included (n\u2009=\u2009831) and followed until 31\/12\/2023 (median 38.5 months).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>In the HD cohort, 71% of the FID patients were dead at the end of follow-up (vs No Iron Deficiency, NID: 52%, AID: 48%; p\u2009=\u20090.008). In the CKD cohort, 62% of the FID group died by the end of follow-up (vs AID: 49.5%, NID: 46.2%; p\u2009=\u20090.001). The hazard ratio for FID for all-cause mortality was 1.89 (p\u2009&lt;\u20090.001) in HD and 1.48 (p\u2009&lt;\u20090.001) in CKD. Multivariate analysis found FID was independently associated with all-cause mortality (HD HR:1.50, p\u2009=\u20090.015; CKD HR: 1.46, p\u2009=\u20090.017). Patients with FID on HD were more likely to be hospitalized (median episodes 2.5 FID vs 2 in AID and NID, p\u2009=\u20090.041; FID: 22.5 days vs AID: 10, NID:14 days, p\u2009=\u20090.019).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>FID was associated with all-cause mortality in patients with non-dialysis CKD and HD, and with higher rates of hospitalization and prolonged length of stay in HD.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0343724","type":"journal-article","created":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T17:39:56Z","timestamp":1774373996000},"page":"e0343724","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Functional iron deficiency and outcomes in patients with kidney 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