{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T20:03:21Z","timestamp":1790193801165,"version":"4.1.0"},"reference-count":28,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2021,11,9]],"date-time":"2021-11-09T00:00:00Z","timestamp":1636416000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2021,11,9]],"date-time":"2021-11-09T00:00:00Z","timestamp":1636416000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100001661","name":"Ruprecht-Karls-Universit\u00e4t Heidelberg","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100001661","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Respir Res"],"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Background<\/jats:title>\n                <jats:p>Iron deficiency affects up to 50% of patients with pulmonary arterial hypertension (PAH) but iron markers such as ferritin and serum iron are confounded by several non-disease related factors like acute inflammation and diet. The aim of this study was to identify a new marker for iron deficiency and clinical outcome in PAH patients.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>In this single-center, retrospective study we assessed indicators of iron status and clinical parameters specifying the time to clinical worsening (TTCW) and survival in PAH patients at time of initial diagnosis and at 1-year follow-up using univariable and multivariable analysis.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>In total, 150 patients were included with an invasively confirmed PAH and complete data on iron metabolism. The proportion of hypochromic erythrocytes\u2009&gt;\u20092% at initial diagnosis was identified as an independent predictor for a shorter TTCW (p\u2009=\u20090.0001) and worse survival (p\u2009=\u20090.002) at initial diagnosis as well as worse survival (p\u2009=\u20090.016) at 1-year follow-up. Only a subset of these patients (64%) suffered from iron deficiency. Low ferritin or low serum iron neither correlated with TTCW nor survival. Severe hemoglobin deficiency at baseline was significantly associated with a shorter TTCW (p\u2009=\u20090.001).<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>The presence of hypochromic erythrocytes\u2009&gt;\u20092% was a strong and independent predictor of mortality and shorter TTCW in this cohort of PAH patients. Thus, it can serve as a valuable indicator of iron homeostasis and prognosis even in patients without iron deficiency or anemia. Further studies are needed to confirm the results and to investigate therapeutic implications.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12931-021-01884-9","type":"journal-article","created":{"date-parts":[[2021,11,9]],"date-time":"2021-11-09T14:03:44Z","timestamp":1636466624000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Prognostic impact of hypochromic erythrocytes in patients with pulmonary arterial hypertension"],"prefix":"10.1186","volume":"22","author":[{"given":"Panagiota","family":"Xanthouli","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vivienne","family":"Theobald","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicola","family":"Benjamin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto M.","family":"Marra","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"D\u2019Agostino","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin","family":"Egenlauf","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Memoona","family":"Shaukat","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cao","family":"Ding","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"Cittadini","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eduardo","family":"Bossone","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"K\u00f6gler","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ekkehard","family":"Gr\u00fcnig","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martina U.","family":"Muckenthaler","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7288-8297","authenticated-orcid":false,"given":"Christina A.","family":"Eichstaedt","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,11,9]]},"reference":[{"key":"1884_CR1","doi-asserted-by":"publisher","first-page":"2007","DOI":"10.1002\/ehf2.12797","volume":"7","author":"VK Chopra","year":"2020","unstructured":"Chopra VK, Anker SD. 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The study complies with the Declaration of Helsinki in its current version.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"PX has received personal fees from MSD and OMT outside the submitted work. VT, MK, MS, DC, AC, AD, MM and CAE declare that they have no competing interests related to this study. AMM has received personal fees from Bayer, outside the submitted work. NB received speaker fees from Actelion pharmaceuticals \/ Janssen Medical, Bayer HealthCare and MSD, outside the submitted work. EG has received grants and personal fees from Actelion, Bayer AG, and MSD; grants from GSK, Novartis, and United Therapeutics; and personal fees from SCOPE, OrPha Swiss GmbH, and Zurich Heart House, outside the submitted work. BE received travel fees, consulting fees, speaking fees, and\/or honoraria from Actelion, MSD, Bayer and OMT, outside the submitted work.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"288"}}