The association between the degree of fever as measured in the emergency department and clinical outcomes of hospitalized adult patients

Published:December 08, 2021DOI:



      Fever is a physiologic response to a wide range of pathologies and one of the most common complaints and clinical signs in the emergency medicine department (ED). The association between fever magnitude and clinical outcomes has been evaluated in specific populations with inconsistent results.


      In this study we aimed to investigate the association between the degree of fever in the ED and clinical outcomes of hospitalized febrile adult patients.


      This was a retrospective single-center cohort study of all the patients with maximal body temperature (BT) ≥ 38.0 °C, as recorded during the ED evaluation, who were hospitalized between January 2015 and December 2020. Patients with heatstroke were excluded. The primary outcome was 30-day all-cause mortality and secondary outcomes were intensive care unit (ICU) admission and development of acute kidney injury (AKI).


      Fever was recorded among 8.1% of patients evaluated in the ED. Elevated BT was associated with increased risk of hospital admission (70.3% vs. 49.4%, p < 0.001), 30-day mortality (12.3% vs. 2.6%, p < 0.001), ICU admission (5.7% vs. 2.8%, p < 0.001), and AKI 11.7% vs. 3.8%, p < 0.001).
      After exclusion of nine patients with heatstroke, 21,252 hospitalized febrile patients were included in the final analysis. BT > 39.7 °C was progressively associated with increased mortality (OR 1.64–2.22, 95% CI 1.16–2.81, p < 0.005) as compared to BT 38.0–38.1 °C. More AKI events were observed in patients with BT > 39.5 °C (OR 1.48–2.91, 95% CI 1.11–3.66, p < 0.007). Temperature between 39.2 and 39.5 °C was associated with lower mortality (OR 0.62–0.71, 95% CI 0.51–0.87, p < 0.001). In a multiple logistic regression analysis BT > 39.9 °C was independently associated with increased mortality and AKI. BT > 39.7 °C was progressively associated with an increased risk of ICU admission.


      Among febrile patients admitted to the hospital, BT > 39.5 °C was associated with adverse clinical course, as compared to patients with lower-grade fever (38.0–38.1 °C). These patients should be flagged on arrival to the ED and likely warrant more aggressive evaluation and treatment.


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        • Young P.
        • Saxena M.
        • Beasley R.
        • Bellomo R.
        • Bailey M.
        • Pilcher D.
        • et al.
        Early peak temperature and mortality in critically ill patients with or without infection.
        Intensive Care Med. 2012 Mar; 38: 437-444
        • Greer D.
        • Funk S.
        • Reaven N.
        • Ouzounelli M.
        • Uman G.
        Impact of fever on outcome in patients with stroke and neurologic injury: a comprehensive meta-analysis.
        Stroke. 2008 Nov 1; 39: 3029-3035
        • DeWitt S.
        • Chavez S.A.
        • Perkins J.
        • Long B.
        • Koyfman A.
        Evaluation of fever in the emergency department.
        Am J Emerg Med. 2017 Nov 1; 35: 1755-1758
        • Rueegg M.
        • Nickel C.H.
        • Bingisser R.
        Disagreements between emergency patients and physicians regarding chief complaint – Patient factors and prognostic implications.
        Int J Clin Pract. 2021 May 1; 75e14070
        • Sundén-Cullberg J.
        • Rylance R.
        • Svefors J.
        • Norrby-Teglund A.
        • Björk J.
        • Inghammar M.
        Fever in the emergency department predicts survival of patients with severe sepsis and septic shock admitted to the ICU∗.
        Crit Care Med. 2017 Apr 1; 45: 591-599
        • Rosenfeld-Yehoshua N.
        • Barkan S.
        • Abu-Kishk I.
        • Booch M.
        • Suhami R.
        • Kozer E.
        Hyperpyrexia and high fever as a predictor for serious bacterial infection (SBI) in children—a systematic review.
        Eur J Pediatr. 2018 Mar 1; 177: 337-344
        • Michelson K.A.
        • Neuman M.I.
        • Pruitt C.M.
        • Desai S.
        • Wang M.E.
        • DePorre A.G.
        • et al.
        Height of fever and invasive bacterial infection.
        Arch Dis Child. 2021 Jun 1; 106: 594-596
        • Egi M.
        • Morita K.
        Fever in non-neurological critically ill patients: a systematic review of observational studies.
        J Crit Care. 2012 Oct; 27: 428-433
        • Reiner Benaim A.
        • Almog R.
        • Gorelik Y.
        • Hochberg I.
        • Nassar L.
        • Mashiach T.
        • et al.
        Analyzing medical research results based on synthetic data and their relation to real data results: systematic comparison from five observational studies.
        JMIR Med Inform. 2020; 8e16492
        • Bijur P.
        • Shah P.
        • Esses D.
        Temperature measurement in the adult emergency department: oral, tympanic membrane and temporal artery temperatures versus rectal temperature.
        Emerg Med J. 2016 Dec 1; 33: 843-847
        • Obermeyer Z.
        • Samra J.K.
        • Mullainathan S.
        Individual differences in normal body temperature: longitudinal big data analysis of patient records.
        BMJ. 2017 Dec 13; 359: 5468
        • Varney S.
        • Manthey D.
        • Culpepper V.
        • Creedon J.
        A comparison of oral, tympanic, and rectal temperature measurement in the elderly.
        J Emerg Med. 2002; 22: 153-157
        • Khwaja A.
        KDIGO clinical practice guidelines for acute kidney injury.
        Nephron. 2012 Aug 7; 120: c179-c184
        • Diringer M.N.
        • Reaven N.L.
        • Funk S.E.U.G.
        Elevated body temperature independently contributes to increased length of stay in neurologic intensive care unit patients.
        Crit Care Med. 2004 Jul; 32: 1489-1495
        • Yamamoto S.
        • Yamazaki S.
        • Shimizu T.
        • Takeshima T.
        • Fukuma S.
        • Yamamoto Y.
        • et al.
        Body temperature at the emergency department as a predictor of mortality in patients with bacterial infection.
        Med. 2016; 95
        • Lee B.H.
        • Inui D.
        • Suh G.Y.
        • Kim J.Y.
        • Kwon J.Y.
        • Park J.
        • et al.
        Association of body temperature and antipyretic treatments with mortality of critically ill patients with and without sepsis: multi-centered prospective observational study.
        Crit Care. 2012; 161 (2012 Feb 28;16(1):): 1-13
        • Casadevall A.
        Thermal restriction as an antimicrobial function of fever.
        PLoS Pathog. 2016 May 1; 12
        • Simpson W.
        Artificial fever therapy of syphilis and gonococcic infections.
        Br J Vener Dis. 1936 Jul 1; 12: 133-166
        • Ye S.
        • Xu D.
        • Zhang C.
        • Li M.
        • Zhang Y.
        Effect of antipyretic therapy on mortality in critically ill patients with sepsis receiving mechanical ventilation treatment.
        Can Respir J. 2017; 2017
        • Schulman C.I.
        • Namias N.
        • Doherty J.
        • Manning R.J.
        • Li P.
        • Elhaddad A.
        • et al.
        The effect of antipyretic therapy upon outcomes in critically ill patients: a randomized, prospective study.
        Surg Infect (Larchmt). 2005; 6: 369-375
        • Jefferies S.
        • Weatherall M.
        • Young P.
        • Eyers S.
        • Perrin K.G.
        • Beasley C.R.W.
        The effect of antipyretic medications on mortality in critically ill patients with infection: a systematic review and meta-analysis.
        Crit Care Resusc J Australas Acad Crit Care Med. 2011 Jun; 13: 125-131
        • Schortgen F.
        • Clabault K.
        • Katsahian S.
        • Devaquet J.
        • Mercat A.
        • Deye N.
        • et al.
        Fever control using external cooling in septic shock.
        (doi:101164/rccm201110-1820OC)185(10). 2012 Dec 14: 1088-1095
        • Mohr N.M.
        • Doerschug K.C.
        Point: should antipyretic therapy be given routinely to febrile patients in septic shock?.
        Yes Chest. 2013 Oct 1; 144: 1096-1098
        • Haupt M.
        • Rackow E.
        Adverse effects of febrile state on cardiac performance.
        Am Heart J. 1983; 105: 763-768
        • Mcilvoy L.
        Comparison of brain temperature to core temperature: a review of the literature.
        J Neurosci Nurs. 2004; 36: 23-31
        • Knott J.C.
        • Tan S.-L.
        • Street A.C.
        • Bailey M.
        • Cameron P.
        Febrile adults presenting to the emergency department: outcomes and markers of serious illness.
        Emerg Med J. 2004 Mar 1; 21: 170-174
        • DP H, SL N, CB L, J H, C P, AT L
        How well do discharge diagnoses identify hospitalised patients with community-acquired infections?--a validation study.
        PLoS One. 2014 Mar 24; 9
        • Cretikos M.A.
        • Bellomo R.
        • Hillman K.
        • Chen J.
        • Finfer S.
        • Flabouris A.
        Respiratory rate: the neglected vital sign.
        Med J Aust. 2008 Jun 2; 188: 657-659
        • Huang S.Y.
        • Greenes D.S.
        Effect of recent antipyretic use on measured fever in the pediatric emergency department.
        Arch Pediatr Adolesc Med. 2004 Oct 1; 158: 972-976