{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T17:01:10Z","timestamp":1791392470518,"version":"4.3.3"},"reference-count":16,"publisher":"Wiley","issue":"5","license":[{"start":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T00:00:00Z","timestamp":1789862400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"},{"start":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T00:00:00Z","timestamp":1789862400000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Muscle and Nerve"],"published-print":{"date-parts":[[2026,11]]},"abstract":"ABSTRACT<\/jats:title>\n \n Introduction\/Aims<\/jats:title>\n Phrenic nerve conduction studies (NCS) are regularly used in the evaluation of neuromuscular respiratory dysfunction; however, the impact of body mass index (BMI) on phrenic compound muscle action potential (CMAP) amplitudes remains poorly characterized. We evaluated the relationship between BMI and phrenic CMAP amplitudes in patients without evidence of neuromuscular diaphragmatic dysfunction.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n We performed a retrospective secondary analysis of patients derived from two previously published cohorts from Mayo Clinic (Rochester, Minnesota) and the University of Alberta (Edmonton, Alberta) evaluating diaphragm ultrasound in suspected neuromuscular respiratory insufficiency. Patients without evidence of neuromuscular disease affecting the diaphragm who underwent bilateral phrenic NCS and diaphragm ultrasound were included.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n Seventy\u2010nine patients met inclusion criteria, including 36 with\n BMI<\/jats:styled-content>\n \u2009\u2265\u200930\u2009kg\/m\n 2<\/jats:sup>\n . Median phrenic\n CMAP<\/jats:styled-content>\n amplitudes were significantly lower in patients with\n BMI<\/jats:styled-content>\n \u2009\u2265\u200930\u2009kg\/m\n 2<\/jats:sup>\n compared to\n BMI<\/jats:styled-content>\n \u2009<\u200930\u2009kg\/m\n 2<\/jats:sup>\n (0.25\u2009\n mV<\/jats:styled-content>\n [\n IQR<\/jats:styled-content>\n 0.10\u20130.38] vs. 0.50\u2009mV [0.30\u20130.65],\n p<\/jats:italic>\n \u2009<\u20090.001). Low phrenic\n CMAP<\/jats:styled-content>\n amplitudes (<\u20090.3\u2009\n mV<\/jats:styled-content>\n ) were more common in patients with obesity (58% vs. 21%,\n p<\/jats:italic>\n \u2009<\u20090.001).\n BMI<\/jats:styled-content>\n demonstrated a moderate negative correlation with phrenic\n CMAP<\/jats:styled-content>\n amplitude (\n \u03c1<\/jats:italic>\n \u2009=\u2009\u22120.50,\n p<\/jats:italic>\n \u2009<\u20090.001). Diaphragm thickness at functional residual capacity did not differ significantly between\n BMI<\/jats:styled-content>\n groups, while diaphragm thickening ratio was modestly lower in obesity.\n <\/jats:p>\n <\/jats:sec>\n \n Discussion<\/jats:title>\n Elevated BMI is associated with lower phrenic CMAP amplitudes in patients without evidence of neuromuscular diaphragmatic dysfunction. Reduced phrenic CMAP amplitudes in obesity may reflect technical recording limitations rather than clinically meaningful diaphragmatic dysfunction. Low\u2010amplitude phrenic responses in patients with obesity should be interpreted cautiously and alongside adjunctive assessments such as diaphragm ultrasound.<\/jats:p>\n <\/jats:sec>","DOI":"10.1002\/mus.70414","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T06:45:44Z","timestamp":1789973144000},"page":"1450-1455","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Reduced Phrenic\n CMAP<\/scp>\n Amplitudes in Obesity Despite Preserved Diaphragm Ultrasound Measures"],"prefix":"10.1002","volume":"74","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7961-7879","authenticated-orcid":false,"given":"Andrea J.","family":"Boon","sequence":"first","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation Mayo Clinic Rochester Minnesota USA"},{"name":"Department of Neurology Mayo Clinic Rochester Minnesota USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6212-1236","authenticated-orcid":false,"given":"Elie","family":"Naddaf","sequence":"additional","affiliation":[{"name":"Department of Neurology Mayo Clinic Rochester Minnesota USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3512-1796","authenticated-orcid":false,"given":"Grayson","family":"Beecher","sequence":"additional","affiliation":[{"name":"Division of Neurology, Department of Medicine University of Alberta Edmonton Alberta Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,9,20]]},"reference":[{"key":"e_1_2_10_2_1","doi-asserted-by":"publisher","DOI":"10.1002\/mus.27998"},{"key":"e_1_2_10_3_1","doi-asserted-by":"publisher","DOI":"10.1002\/mus.26414"},{"key":"e_1_2_10_4_1","doi-asserted-by":"publisher","DOI":"10.1097\/WNP.0000000000001181"},{"key":"e_1_2_10_5_1","doi-asserted-by":"publisher","DOI":"10.1002\/mus.20887"},{"key":"e_1_2_10_6_1","doi-asserted-by":"publisher","DOI":"10.1002\/mus.880180311"},{"key":"e_1_2_10_7_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-022-11930-1"},{"key":"e_1_2_10_8_1","doi-asserted-by":"publisher","DOI":"10.1002\/mus.24059"},{"key":"e_1_2_10_9_1","doi-asserted-by":"publisher","DOI":"10.1016\/S1388-2457(00)00250-9"},{"key":"e_1_2_10_10_1","doi-asserted-by":"crossref","unstructured":"S. D.Emmerich C. D.Fryar B.Stierman andC. L.Ogden \u201cObesity and Severe Obesity Prevalence in Adults: United States August 2021\u2010August 2023 \u201d NCHS Data Brief 2024(508).","DOI":"10.15620\/cdc\/159281"},{"key":"e_1_2_10_11_1","doi-asserted-by":"publisher","DOI":"10.1503\/cmaj.241421"},{"key":"e_1_2_10_12_1","doi-asserted-by":"publisher","DOI":"10.1212\/WNL.0000000000000841"},{"key":"e_1_2_10_13_1","doi-asserted-by":"publisher","DOI":"10.1002\/mus.28194"},{"key":"e_1_2_10_14_1","doi-asserted-by":"publisher","DOI":"10.1002\/mus.23702"},{"key":"e_1_2_10_15_1","doi-asserted-by":"publisher","DOI":"10.1002\/(SICI)1097-4598(199811)21:11<1398::AID-MUS6>3.0.CO;2-4"},{"key":"e_1_2_10_16_1","doi-asserted-by":"publisher","DOI":"10.1002\/mus.28403"},{"key":"e_1_2_10_17_1","doi-asserted-by":"publisher","DOI":"10.1002\/mus.28076"}],"container-title":["Muscle & Nerve"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/mus.70414","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/mus.70414","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/mus.70414","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T16:43:06Z","timestamp":1791391386000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/mus.70414"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,20]]},"references-count":16,"journal-issue":{"issue":"5","published-print":{"date-parts":[[2026,11]]}},"alternative-id":["10.1002\/mus.70414"],"URL":"https:\/\/doi.org\/10.1002\/mus.70414","archive":["Portico"],"relation":{},"ISSN":["0148-639X","1097-4598"],"issn-type":[{"value":"0148-639X","type":"print"},{"value":"1097-4598","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,20]]},"assertion":[{"value":"2026-05-31","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-09-15","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-09-20","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}