{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T04:59:58Z","timestamp":1785214798308,"version":"3.55.0"},"reference-count":39,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T00:00:00Z","timestamp":1785196800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Stroke"],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>The relationship between hemoglobin concentration and all-cause mortality in acute ischemic stroke (AIS) patients remains unclear due to conflicting findings. This study aims to evaluate the impact of hemoglobin concentration on the risk of both short-term and long-term all-cause mortality in AIS patients from a nationwide stroke registry.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Method<\/jats:title>\n                    <jats:p>We utilized data from the Singapore Stroke Registry (SSR), including patients &amp;gt;18years old at first AIS onset, and received treatment at a local hospital between 2005 and 2020. Patients were stratified according to sex-specific hemoglobin concentration cut-offs on anemia severity and polycythemia from the World Health Organization. Multivariate logistic regression and Cox proportional hazards modeling were performed, adjusting for demographics and cardiovascular risk factors.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A total of 56,884 ischemic stroke patients were included, of which 66.8% had no anemia, 15.7% had mild anemia, 12.2% had severe anemia, and 5.3% had polycythemia. The cohort was predominantly male (57%), with a median age of 68 years. The median follow-up duration was 10-years (IQR 7\u201313). Compared to patients with normal-range hemoglobin, both mild and severe anemia was associated with elevated short-term and long-term risks of all-cause mortality. Severe anemia was associated with the highest risk of all-cause mortality, with hazard ratios of 1.99 (95%CI:1.92\u20132.06) at 30-days, 1.73 (95%CI:1.66\u20131.81) at 1-year, and 1.52 (95%CI:1.41\u20131.64) at 5-years. However, the excess risk associated with severe anemia appeared to attenuate at 10-years, whilst the elevated risk persisted among patients with mild anemia.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>In this nationwide stroke registry, anemia is prevalent among AIS patients and is significantly associated with both short-term and long-term mortality.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fstro.2026.1859301","type":"journal-article","created":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T04:25:15Z","timestamp":1785212715000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Anemia impacts short-term and long-term mortality risk after acute ischemic stroke"],"prefix":"10.3389","volume":"5","author":[{"given":"Chen Ee","family":"Low","sequence":"first","affiliation":[{"name":"Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore","place":["Singapore, Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hon Jen","family":"Wong","sequence":"additional","affiliation":[{"name":"Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore","place":["Singapore, Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chun En","family":"Yau","sequence":"additional","affiliation":[{"name":"Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore","place":["Singapore, Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jia Yang","family":"Tan","sequence":"additional","affiliation":[{"name":"Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore","place":["Singapore, Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yao Neng","family":"Teo","sequence":"additional","affiliation":[{"name":"Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore","place":["Singapore, Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yao Hao","family":"Teo","sequence":"additional","affiliation":[{"name":"Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore","place":["Singapore, Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jasper R.","family":"Senff","sequence":"additional","affiliation":[{"name":"Department of Neurology, Massachusetts General Hospital, Boston","place":["MA, United States"]},{"name":"Department of Neurology, University Medical Center Utrecht","place":["Utrecht, Netherlands"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Reinier","family":"Tack","sequence":"additional","affiliation":[{"name":"Department of Neurology, Massachusetts General Hospital, Boston","place":["MA, United States"]},{"name":"Department of Neurology, University Medical Center Utrecht","place":["Utrecht, Netherlands"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew F. 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