{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T19:26:00Z","timestamp":1774466760943,"version":"3.50.1"},"reference-count":23,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T00:00:00Z","timestamp":1769817600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T00:00:00Z","timestamp":1769817600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100000050","name":"National Heart, Lung, and Blood Institute","doi-asserted-by":"publisher","award":["HL156812"],"award-info":[{"award-number":["HL156812"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000738","name":"U.S. Department of Veterans Affairs","doi-asserted-by":"publisher","award":["IK2CX001882"],"award-info":[{"award-number":["IK2CX001882"]}],"id":[{"id":"10.13039\/100000738","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100006108","name":"National Center for Advancing Translational Sciences","doi-asserted-by":"publisher","award":["UM1TR004528"],"award-info":[{"award-number":["UM1TR004528"]}],"id":[{"id":"10.13039\/100006108","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Sleep Breath"],"published-print":{"date-parts":[[2026,3]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>In a Long Haul COVID referral clinic we describe the primary presentations of fatigue according to the CDC 2015 criteria for myalgic encephalitis\/chronic fatigue syndrome (ME\/CFS).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Between September 2021 and April 2022, 277 patients (61% women, 54 yrs: range 18\u201390 yrs) presented an average of 10 months after an acute COVID-19 infection (22% hospitalized). The clinical data were analyzed to conpare those with or without a primary or co-primary complaint of fatigue, subdivided as meeting ME\/CFS criteria or not.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      209 (73.5%) people (64% women) presented with fatigue. The Fatigue Severity Score was 5.33 (out 7) in those with 5.31 (SD1.54) vs. without 4.43 (SD1.65) a primary fatigue complaint (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&gt;\u20090.001). Anxiety (58% vs. 38%,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.02) and any psychiatric diagnosis (66% vs. 44%%,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.01), but not depression itself, were overrepresented in those with Fatigue and ME\/CFS. Those with prior managed sleep conditions did not increase risk for fatigue presentation. Of those with fatigue and an elevated FSS, 45\/209 (21.9%) met criteria for ME\/CFS. In those not meeting these criteria, associated ME\/CFS symptoms were less consistent. Physical functioning by ECOG (1.88 (0.78) and 26% &gt;2) did correlate with fatigue status. Depression was present (PHQ9 12.34 (5.95) with 63% &gt;10) to a moderate or higher degree and was different with fatigue complaints. Brain fog (51.9%) was similar among the three categories, and correlated with FSS\u2009&gt;\u20094, ECOG, and depression.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>The fatigue phenotype in those presenting with it as a primary complaint comprises 21% meeting ME\/CFS criteria and 79% which do not. In all the Long Haul COVID presentations. brain fog had separate, distinguishing features. Post-COVID fatigue is a spectrum which will confound clinical trials.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s11325-025-03512-y","type":"journal-article","created":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T17:06:18Z","timestamp":1769879178000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The fatigue spectrum in a community-based long haul COVID cohort"],"prefix":"10.1007","volume":"30","author":[{"given":"Isabelle V.","family":"Carter","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anna","family":"May","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Isabella C.","family":"Hsieh","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juliane","family":"Torer","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David","family":"Rosenberg","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7740-9013","authenticated-orcid":false,"given":"Kingman P.","family":"Strohl","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2026,1,31]]},"reference":[{"issue":"18","key":"3512_CR1","doi-asserted-by":"publisher","first-page":"1746","DOI":"10.1056\/NEJMsb2408466","volume":"391","author":"EW Ely","year":"2024","unstructured":"Ely EW, Brown LM, Fineberg HV (2024) Long covid defined. 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The data of this study will be shared on reasonable request to the corresponding authors.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of Interest"}}],"article-number":"27"}}