{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,29]],"date-time":"2026-10-29T06:22:34Z","timestamp":1793254954200,"version":"4.5.0"},"reference-count":33,"publisher":"Oxford University Press (OUP)","issue":"8","license":[{"start":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T00:00:00Z","timestamp":1769040000000},"content-version":"vor","delay-in-days":1027,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"name":"RWTH Aachen Faculty of Medicine","award":["START Grant supporting the junior research group around Dr. Jens Spiesshoefer"],"award-info":[{"award-number":["START Grant supporting the junior research group around Dr. Jens Spiesshoefer"]}]},{"name":"RWTH Aachen Faculty of Medicine","award":["START Grant supporting the junior research group around Dr. Jens Spiesshoefer"],"award-info":[{"award-number":["START Grant supporting the junior research group around Dr. Jens Spiesshoefer"]}]}],"content-domain":{"domain":["www.atsjournals.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2023,4,15]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Rationale<\/jats:title>\n                    <jats:p>Dyspnea is often a persistent symptom after acute coronavirus disease (COVID-19), even if cardiac and pulmonary function are normal.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>This study investigated diaphragm muscle strength in patients after COVID-19 and its relationship to unexplained dyspnea on exertion.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Fifty patients previously hospitalized with COVID-19 (14 female, age 58\u2009\u00b1\u200912 yr, half of whom were treated with mechanical ventilation, and half of whom were treated outside the ICU) were evaluated using pulmonary function testing, 6-minute-walk test, echocardiography, twitch transdiaphragmatic pressure after cervical magnetic stimulation of the phrenic nerve roots, and diaphragm ultrasound. Diaphragm function data were compared with values from a healthy control group.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Measurements and Main Results<\/jats:title>\n                    <jats:p>Moderate or severe dyspnea on exertion was present at 15 months after hospital discharge in approximately two-thirds of patients. No significant pulmonary function or echocardiography abnormalities were detected. Twitch transdiaphragmatic pressure was significantly impaired in patients previously hospitalized with COVID-19 compared with control subjects, independent of initial disease severity (14\u2009\u00b1\u20098 vs. 21\u2009\u00b1\u20093 cm H2O in mechanically ventilated patients vs. control subjects [P\u2009=\u20090.02], and 15\u2009\u00b1\u20098 vs. 21\u2009\u00b1\u20093 cm H2O in nonventilated patients vs. control subjects [P\u2009=\u20090.04]). There was a significant association between twitch transdiaphragmatic pressure and the severity of dyspnea on exertion (P\u2009=\u20090.03).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Diaphragm muscle weakness was present 15 months after hospitalization for COVID-19 even in patients who did not require mechanical ventilation, and this weakness was associated with dyspnea on exertion. The current study, therefore, identifies diaphragm muscle weakness as a correlate for persistent dyspnea in patients after COVID-19 in whom lung and cardiac function are normal.<\/jats:p>\n                    <jats:p>Clinical trial registered with www.clinicaltrials.gov (NCT 04854863).<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1164\/rccm.202206-1243oc","type":"journal-article","created":{"date-parts":[[2023,1,3]],"date-time":"2023-01-03T16:12:20Z","timestamp":1672762340000},"page":"1012-1021","update-policy":"https:\/\/doi.org\/10.1164\/crossmarkpolicies","source":"Crossref","is-referenced-by-count":49,"title":["Diaphragm Muscle Weakness Might Explain Exertional Dyspnea 15 Months after Hospitalization for COVID-19"],"prefix":"10.1093","volume":"207","author":[{"given":"Binaya","family":"Regmi","sequence":"first","affiliation":[{"name":"Department of Pneumology and Intensive Care Medicine, University Hospital RWTH Aachen, Aachen, 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Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthias","family":"Boentert","sequence":"additional","affiliation":[{"name":"Department of Neurology with Institute for Translational Neurology, University Hospital of Muenster, Muenster, Germany; and"},{"name":"Department of Medicine, UKM Marienhospital Steinfurt, Steinfurt, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ayham","family":"Daher","sequence":"additional","affiliation":[{"name":"Department of Pneumology and Intensive Care Medicine, University Hospital RWTH Aachen, Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Dreher","sequence":"additional","affiliation":[{"name":"Department of Pneumology and Intensive Care Medicine, University Hospital RWTH Aachen, Aachen, 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