Body Mass Index and Mortality in Blunt Trauma: The Right BMI can be Protective

Am J Surg. 2020 Dec;220(6):1475-1479. doi: 10.1016/j.amjsurg.2020.10.017. Epub 2020 Oct 13.

Abstract

Background: There are limited studies examining the role of BMI on mortality in the trauma population. The aim of this study was to analyze whether the "obesity paradox" exists in non-elderly patients with blunt trauma.

Methods: A retrospective study was performed on the Trauma Quality Improvement Program (TQIP) database for 2016. All non-elderly patients aged 18-64, with blunt traumatic injuries were identified. A generalized additive model (GAM) was built to assess the association of mortality and BMI adjusted for age, gender, race, and injury severity score (ISS).

Results: 28,475 patients (mean age = 42.5, SD = 14.3) were identified. 20,328 (71.4%) were male. Age (p < 0.0001), gender (p < 0.0001), and ISS (p < 0.0001) had significant associations with mortality. After GAM, BMI showed a significant U-shaped association with mortality (EDF = 3.2, p = 0.003). A BMI range of 31.5 ± 0.9 kg/m2 was associated with the lowest mortality.

Conclusion: High BMI can be a protective factor in mortality within non-elderly patients with blunt trauma. However, underweight or morbid obesity suggest a higher risk of mortality.

Keywords: Blunt trauma; Generalized additive model; Obesity; Obesity paradox; Retrospective.

MeSH terms

  • Adolescent
  • Adult
  • Body Mass Index*
  • Female
  • Humans
  • Injury Severity Score
  • Length of Stay / statistics & numerical data
  • Male
  • Middle Aged
  • Obesity, Morbid / complications
  • Retrospective Studies
  • Risk Factors
  • Thinness / complications
  • Wounds, Nonpenetrating / mortality*