Sex-Based Differences in Inpatient Burn Mortality

  • Felicia N. WilliamsEmail author
  • Paula D. Strassle
  • Laquanda Knowlin
  • Sonia Napravnik
  • David van Duin
  • Anthony Charles
  • Rabia Nizamani
  • Samuel W. Jones
  • Bruce A. Cairns
Original Scientific Report



Among burn patients, research is conflicted, but may suggest that females are at increased risk of mortality, despite the opposite being true in non-burn trauma. Our objective was to determine whether sex-based differences in burn mortality exist, and assess whether patient demographics, comorbid conditions, and injury characteristics explain said differences.


Adult patients admitted with burn injury—including inhalation injury only—between 2004 and 2013 were included. Inverse probability of treatment weights (IPTW) and inverse probability of censor weights (IPCW) were calculated using admit year, patient demographics, comorbid conditions, and injury characteristics to adjust for potential confounding and informative censoring. Standardized Kaplan–Meier survival curves, weighted by both IPTW and IPCW, were used to estimate the 30-day and 60-day risk of inpatient mortality across sex.


Females were older (median age 44 vs. 41 years old, p < 0.0001) and more likely to be Black (32% vs. 25%, p < 0.0001), have diabetes (14% vs. 10%, p < 0.0001), pulmonary disease (14% vs. 7%, p < 0.0001), heart failure (4% vs. 2%, p = 0.001), scald burns (45% vs. 26%, p < 0.0001), and inhalational injuries (10% vs. 8%, p = 0.04). Even after weighting, females were still over twice as likely to die after 60 days (RR 2.87, 95% CI 1.09, 7.51).


Female burn patients have a significantly higher risk of 60-day mortality, even after accounting for demographics, comorbid conditions, burn size, and inhalational injury. Future research efforts and treatments to attenuate mortality should account for these sex-based differences. The project was supported by the National Institutes of Health, Grant Number UL1TR001111.



The project described was supported by the National Center for Advancing Translational Sciences (NCATS), National Institutes of Health, through Grant Award No. UL1TR001111. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

The study was approved by our institutional review board (IRB).


  1. 1.
    Al-Tarrah K, Moiemen N, Lord JM (2017) The influence of sex steroid hormones on the response to trauma and burn injury. Burns Trauma 5:29CrossRefGoogle Scholar
  2. 2.
    Williams FN, Jeschke MG, Chinkes DL et al (2009) Modulation of the hypermetabolic response to trauma: temperature, nutrition, and drugs. J Am Coll Surg 208:489–502CrossRefGoogle Scholar
  3. 3.
    Colohan SM (2010) Predicting prognosis in thermal burns with associated inhalational injury: a systematic review of prognostic factors in adult burn victims. J Burn Care Res 31:529–539CrossRefGoogle Scholar
  4. 4.
    Rashid A, Khanna A, Gowar JP et al (2001) Revised estimates of mortality from burns in the last 20 years at the Birmingham Burns Centre. Burns 27:723–730CrossRefGoogle Scholar
  5. 5.
    Roberts G, Lloyd M, Parker M et al (2012) The Baux score is dead. Long live the Baux score: a 27-year retrospective cohort study of mortality at a regional burns service. J Trauma Acute Care Surg 72:251–256CrossRefGoogle Scholar
  6. 6.
    Ryan CM, Schoenfeld DA, Thorpe WP et al (1998) Objective estimates of the probability of death from burn injuries. N Engl J Med 338:362–366CrossRefGoogle Scholar
  7. 7.
    Gomez M, Wong DT, Stewart TE et al (2008) The FLAMES score accurately predicts mortality risk in burn patients. J Trauma 65:636–645CrossRefGoogle Scholar
  8. 8.
    Tobiasen J, Hiebert JM, Edlich RF (1982) The abbreviated burn severity index. Ann Emerg Med 11:260–262CrossRefGoogle Scholar
  9. 9.
    Angele MK, Frantz MC, Chaudry IH (2006) Gender and sex hormones influence the response to trauma and sepsis: potential therapeutic approaches. Clinics (Sao Paulo) 61:479–488CrossRefGoogle Scholar
  10. 10.
    Bedri H, Romanowski KS, Liao J et al (2017) A national study of the effect of race, socioeconomic status, and gender on burn outcomes. J Burn Care Res 38:161–168CrossRefGoogle Scholar
  11. 11.
    Wilmore D, Pruitt BA Jr (1972) Do fat boys get burned? Lancet 2:1083CrossRefGoogle Scholar
  12. 12.
    Wilmore DW, Pruitt BA Jr (1972) Fat boys get burned. Lancet 2:631–632CrossRefGoogle Scholar
  13. 13.
    Osler T, Glance LG, Hosmer DW (2010) Simplified estimates of the probability of death after burn injuries: extending and updating the Baux score. J Trauma 68:690–697CrossRefGoogle Scholar
  14. 14.
    Cole SR, Hernan MA (2004) Adjusted survival curves with inverse probability weights. Comput Methods Programs Biomed 75:45–49CrossRefGoogle Scholar
  15. 15.
    Knowlin L, Reid T, Williams F et al (2017) Burn mortality in patients with preexisting cardiovascular disease. Burns 43:949–955CrossRefGoogle Scholar
  16. 16.
    Knowlin L, Strassle PD, Williams FN et al (2018) Burn injury outcomes in patients with pre-existing diabetic mellitus: risk of hospital-acquired infections and inpatient mortality. Burns 44:272–279CrossRefGoogle Scholar
  17. 17.
    Knowlin LT, Stanford LB, Cairns BA et al (2017) The effect of preexisting respiratory co-morbidities on burn outcomes. Burns 43:366–373CrossRefGoogle Scholar
  18. 18.
    Strassle PD, Williams FN, Napravnik S et al (2017) Improved survival of patients with extensive burns: trends in patient characteristics and mortality among burn patients in a tertiary care burn facility, 2004–2013. J Burn Care Res 38:187–193CrossRefGoogle Scholar
  19. 19.
    Knowlin L, Stanford L, Moore D et al (2016) The measured effect magnitude of co-morbidities on burn injury mortality. Burns 42:1433–1438CrossRefGoogle Scholar
  20. 20.
    Li T, Xiao X, Zhang J et al (2014) Age and sex differences in vascular responsiveness in healthy and trauma patients: contribution of estrogen receptor-mediated Rho kinase and PKC pathways. Am J Physiol Heart Circ Physiol 306:H1105–1115CrossRefGoogle Scholar
  21. 21.
    Liu T, Xie J, Yang F et al (2015) The influence of sex on outcomes in trauma patients: a meta-analysis. Am J Surg 210:911–921CrossRefGoogle Scholar
  22. 22.
    Moore EC, Pilcher D, Bailey M et al (2014) Women are more than twice as likely to die from burns as men in Australia and New Zealand: an unexpected finding of the Burns Evaluation And Mortality (BEAM) Study. J Crit Care 29:594–598CrossRefGoogle Scholar
  23. 23.
    Raju R, Chaudry IH (2008) Sex steroids/receptor antagonist: their use as adjuncts after trauma-hemorrhage for improving immune/cardiovascular responses and for decreasing mortality from subsequent sepsis. Anesth Analg 107:159–166CrossRefGoogle Scholar
  24. 24.
    Offner PJ, Moore EE, Biffl WL (1999) Male gender is a risk factor for major infections after surgery. Arch Surg 134:935–938 (discussion 938–940)CrossRefGoogle Scholar
  25. 25.
    Weniger M, Angele MK, Chaudry IH (2016) The role and use of estrogens following trauma. Shock 46:4–11CrossRefGoogle Scholar
  26. 26.
    Karimi K, Faraklas I, Lewis G et al (2017) Increased mortality in women: sex differences in burn outcomes. Burns Trauma 5:18CrossRefGoogle Scholar
  27. 27.
    Deitch EA, Ananthakrishnan P, Cohen DB et al (2006) Neutrophil activation is modulated by sex hormones after trauma-hemorrhagic shock and burn injuries. Am J Physiol Heart Circ Physiol 291:H1456–1465CrossRefGoogle Scholar
  28. 28.
    Yao X, Wigginton JG, Maass DL et al (2014) Estrogen-provided cardiac protection following burn trauma is mediated through a reduction in mitochondria-derived DAMPs. Am J Physiol Heart Circ Physiol 306:H882–894CrossRefGoogle Scholar
  29. 29.
    Gregory MS, Faunce DE, Duffner LA et al (2000) Gender difference in cell-mediated immunity after thermal injury is mediated, in part, by elevated levels of interleukin-6. J Leukoc Biol 67:319–326CrossRefGoogle Scholar
  30. 30.
    Calvin M (2000) Oestrogens and wound healing. Maturitas 34:195–210CrossRefGoogle Scholar
  31. 31.
    Gilliver SC, Ashcroft GS (2007) Sex steroids and cutaneous wound healing: the contrasting influences of estrogens and androgens. Climacteric 10:276–288CrossRefGoogle Scholar
  32. 32.
    Kerby JD, McGwin G Jr, George RL et al (2006) Sex differences in mortality after burn injury: results of analysis of the National Burn Repository of the American Burn Association. J Burn Care Res 27:452–456CrossRefGoogle Scholar
  33. 33.
    George RL, McGwin G Jr, Schwacha MG et al (2005) The association between sex and mortality among burn patients as modified by age. J Burn Care Rehabil 26:416–421CrossRefGoogle Scholar
  34. 34.
    Gregory MS, Duffner LA, Faunce DE et al (2000) Estrogen mediates the sex difference in post-burn immunosuppression. J Endocrinol 164:129–138CrossRefGoogle Scholar
  35. 35.
    Damas P, Ledoux D, Nys M et al (1992) Cytokine serum level during severe sepsis in human IL-6 as a marker of severity. Ann Surg 215:356–362CrossRefGoogle Scholar
  36. 36.
    Eitas TK, Stepp W, Sjeklocha L et al (2017) Differential regulation of innate immune cytokine production through pharmacological activation of Nuclear Factor-Erythroid-2-Related Factor 2 (NRF2) in burn patient immune cells and monocytes. PLoS ONE 12:e0184164CrossRefGoogle Scholar
  37. 37.
    Gregory MS, Duffner LA, Hahn EL et al (2000) Differential production of prostaglandin E(2) in male and female mice subjected to thermal injury contributes to the gender difference in immune function: possible role for 15-hydroxyprostaglandin dehydrogenase. Cell Immunol 205:94–102CrossRefGoogle Scholar
  38. 38.
    Hack CE, De Groot ER, Felt-Bersma RJ et al (1989) Increased plasma levels of interleukin-6 in sepsis. Blood 74:1704–1710Google Scholar
  39. 39.
    Brahmbhatt TS, Hernon M, Siegert CJ et al (2017) Trauma and BMI mortality. Curr Obes Rep 6:211–216CrossRefGoogle Scholar
  40. 40.
    Diebel ME, Diebel LN, Liberati DM (2016) Gender dimorphism in adipose tissue response to stress conditions: a plausible mechanism to explain the conflicting data regarding trauma and obesity. J Trauma Acute Care Surg 81:1028–1034CrossRefGoogle Scholar
  41. 41.
    Liu T, Chen JJ, Bai XJ et al (2013) The effect of obesity on outcomes in trauma patients: a meta-analysis. Injury 44:1145–1152CrossRefGoogle Scholar
  42. 42.
    Dissanaike S, Ha D, Mitchell D et al (2017) Socioeconomic status, gender, and burn injury: a retrospective review. Am J Surg 214:677–681CrossRefGoogle Scholar
  43. 43.
    Doctor N, Yang S, Maerzacker S et al (2016) Socioeconomic status and outcomes after burn injury. J Burn Care Res 37:e56–62CrossRefGoogle Scholar
  44. 44.
    Edelman LS (2007) Social and economic factors associated with the risk of burn injury. Burns 33:958–965CrossRefGoogle Scholar
  45. 45.
    Seney ML, Huo Z, Cahill K et al (2018) Opposite molecular signatures of depression in men and women. Biol Psychiatry. Google Scholar
  46. 46.
    Wasiak J, Lee SJ, Paul E et al (2017) Female patients display poorer burn-specific quality of life 12 months after a burn injury. Injury 48:87–93CrossRefGoogle Scholar
  47. 47.
    Wasiak J, Lee SJ, Paul E et al (2014) Predictors of health status and health- related quality of life 12 months after severe burn. Burns 40:568–574CrossRefGoogle Scholar
  48. 48.
    Wolf SE, Rose JK, Desai MH et al (1997) Mortality determinants in massive pediatric burns. An analysis of 103 children with > or = 80% TBSA burns (> or = 70% full-thickness). Ann Surg 225:554–565 (discussion 565–559)CrossRefGoogle Scholar
  49. 49.
    FitzGerald C, Hurst S (2017) Implicit bias in healthcare professionals: a systematic review. BMC Med Ethics 18:19CrossRefGoogle Scholar
  50. 50.
    Forster NA, Zingg M, Haile SR et al (2011) 30 years later: does the ABSI need revision? Burns 37:958–963CrossRefGoogle Scholar

Copyright information

© Société Internationale de Chirurgie 2019

Authors and Affiliations

  • Felicia N. Williams
    • 1
    • 2
    Email author
  • Paula D. Strassle
    • 1
    • 3
  • Laquanda Knowlin
    • 4
  • Sonia Napravnik
    • 3
    • 5
  • David van Duin
    • 5
  • Anthony Charles
    • 1
  • Rabia Nizamani
    • 1
    • 2
  • Samuel W. Jones
    • 1
    • 2
  • Bruce A. Cairns
    • 1
    • 2
  1. 1.Department of SurgeryUniversity of North Carolina School of MedicineChapel HillUSA
  2. 2.Department of SurgeryNorth Carolina Jaycee Burn CenterChapel HillUSA
  3. 3.Department of EpidemiologyUniversity of North Carolina at Chapel HillChapel HillUSA
  4. 4.Department of SurgeryHoward UniversityWashingtonUSA
  5. 5.Division of Infectious DiseasesUniversity of North Carolina School of MedicineChapel HillUSA

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