{"pk":8486,"title":"Validation of a Decision Rule for Selective  TSH Screening in Atrial Fibrillation","subtitle":null,"abstract":"Introduction:\n Atrial fibrillation (AF) is the most common cardiac dysrhythmia. Current guidelines recommend obtaining thyroid-stimulating hormone (TSH) levels in all patients presenting with AF.Our aim was to investigate the utility of TSH levels for emergency department (ED) patients with a final diagnosis of AF while externally validating and potentially refining a clinical decision rule that recommends obtaining TSH levels only in patients with previous stroke, hypertension, or thyroid disease. \nMethods: \nWe conducted a retrospective, cross-sectional study of consecutive patients who presented to an ED from January 2011 to March 2014 with a final ED diagnosis of AF. Charts were reviewed for historical features and TSH level. We assessed the sensitivity and specificity of the previously derived clinical decision rule.\nResults: \nOf the 1,964 patients who were eligible, 1,458 (74%) had a TSH level available for analysis. The overall prevalence of a low TSH (<0.3µIU/mL) was 2% (n=36). Elevated TSH levels (>5µIU/mL) were identified in 11% (n=159). The clinical decision rule had a sensitivity of 88.9% (95% CI [73.0-96.4]) and a specificity of 27.5% (95% CI [25.2-29.9]) for identifying a low TSH. When analyzed for its ability to identify any abnormal TSH values (high or low TSH), the sensitivity and specificity were 74.4% (95% CI [67.5-80.2]) and 27.3% (95% CI [24.9-29.9]), respectively. \nConclusion: \nLow TSH in patients presenting to the ED with a final diagnosis of AF is rare (2%). The sensitivity of a clinical decision rule including a history of thyroid disease, hypertension, or stroke for identifying low TSH levels in patients presenting to the ED with a final diagnosis of atrial fibrillation was lower than originally reported (88.9% vs. 93%). When elevated TSH levels were included as an outcome, the sensitivity was reduced to 74.4%. We recommend that emergency medicine providers not routinely order TSH levels for all patients with a primary diagnosis of AF. Instead, these investigations can be limited to patients with new onset AF or those with a history of thyroid disease with no known TSH level within three months . [West J Emerg Med. 2015;16(1):–0.]","language":"en","license":{"name":"Creative Commons Attribution 4.0","short_name":"CC BY 4.0","text":"Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.\r\n\r\nNo additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.","url":"https://creativecommons.org/licenses/by/4.0"},"keywords":[{"word":"atrial fibrillation"},{"word":"clinical decision rule"},{"word":"routine testing"},{"word":"thyroid stimulating hormone"},{"word":"hyperthyroid"},{"word":"hypothyroid"}],"section":"Technology in Emergency Medicine","is_remote":true,"remote_url":"https://escholarship.org/uc/item/8jk2q8sb","frozenauthors":[{"first_name":"Shawna","middle_name":"D.","last_name":"Bellew","name_suffix":"","institution":"Mayo Clinic, Department of Emergency Medicine, Rochester, Minnesota","department":"None"},{"first_name":"Rajat","middle_name":"","last_name":"Moman","name_suffix":"","institution":"Mayo Medical School, Rochester, Minnesota","department":"None"},{"first_name":"Christine","middle_name":"M.","last_name":"Lohse","name_suffix":"","institution":"Mayo Clinic, Department of Health Sciences Research, Division of Biostatistics, Rochester, Minnesota","department":"None"},{"first_name":"Erik","middle_name":"P","last_name":"Hess","name_suffix":"","institution":"Mayo Clinic, Department of Emergency Medicine, Rochester, Minnesota; Mayo Clinic, Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, Rochester, Minnesota","department":"None"},{"first_name":"M. Fernanda","middle_name":"","last_name":"Bellolio","name_suffix":"","institution":"Mayo Clinic, Department of Emergency Medicine, Rochester, Minnesota; Mayo Clinic, Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, Rochester, Minnesota","department":"None"}],"date_submitted":"2014-08-10T23:42:10Z","date_accepted":"2014-08-10T23:42:10Z","date_published":"2015-01-06T01:31:07Z","render_galley":null,"galleys":[{"label":"","type":"pdf","path":"https://journalpub.escholarship.org/westjem/article/8486/galley/4898/download/"}]}