title: Obese patients who fall have less injury severity but a longer hospital stay than normal-weight patients.
abstract: BACKGROUND
  The effects of obesity on injury severity and outcome have been studied in trauma patients but not in those who have experienced a fall. The aim of this study was to compare injury patterns, injury severities, mortality rates, and in-hospital or intensive care unit (ICU) length of stay (LOS) between obese and normal-weight patients following a fall.
  
  
  METHODS
  Detailed data were retrieved for 273 fall-related hospitalized obese adult patients with a body mass index (BMI) ≥30 kg/m(2) and 2357 normal-weight patients with a BMI <25 kg/m(2) but ≥18.5 kg/m(2) from the Trauma Registry System of a Level I trauma center between January 1, 2009, and December 31, 2013. We used the Pearson's chi-squared test, Fisher's exact test, the Mann Whitney U test, and independent Student's t-test to analyze differences between the two groups.
  
  
  RESULTS
  Analysis of AIS scores and AIS severity scaling from 1 to 5 revealed no significant differences in trauma regions between obese and normal-weight patients. When stratified by injury severity (Injury Severity Score [ISS] of <16, 16-24, or ≥25), more obese patients had an ISS of <16 compared to normal-weight patients (90.5 % vs. 86.0 %, respectively; p = 0.041), while more normal-weight patients had an ISS between 16 and 24 (11.0 % vs. 6.6 %, respectively; p = 0.025). Obese patients who had experienced a fall had a significantly lower ISS (median (range): 9 (1-45) vs. 9 (1-50), respectively; p = 0.015) but longer in-hospital LOS than did normal-weight patients (10.1 days vs. 8.9 days, respectively; p = 0.049). Even after taking account of possible differences in comorbidity and ISS, the obese patients have an average 1.54 day longer LOS than that of normal-weight patients. However, no significant differences were found between obese and normal-weight patients in terms of the New Injury Severity Score (NISS), Trauma-Injury Severity Score (TRISS), mortality, percentage of patients admitted to the ICU, or LOS in the ICU.
  
  
  CONCLUSIONS
  Obese patients who had experienced a fall did not have different injured body regions than did normal-weight patients. However, they had a lower ISS but a longer in-hospital LOS than did normal-weight patients.
authors.affiliation: Department of Trauma Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, No.123, Ta-Pei Road, Niao-Sung District, Kaohsiung City, 833 Taiwan.
authors.forename: Jung-Fang
authors.initials: JF
authors.lastname: Chuang
authors.affiliation: Department of Neurosurgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Cheng-Shyuan
authors.initials: CS
authors.lastname: Rau
authors.affiliation: Department of Trauma Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, No.123, Ta-Pei Road, Niao-Sung District, Kaohsiung City, 833 Taiwan.
authors.forename: Hang-Tsung
authors.initials: HT
authors.lastname: Liu
authors.affiliation: Department of Anesthesiology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Shao-Chun
authors.initials: SC
authors.lastname: Wu
authors.affiliation: Department of Trauma Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, No.123, Ta-Pei Road, Niao-Sung District, Kaohsiung City, 833 Taiwan.
authors.forename: Yi-Chun
authors.initials: YC
authors.lastname: Chen
authors.affiliation: Department of Trauma Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, No.123, Ta-Pei Road, Niao-Sung District, Kaohsiung City, 833 Taiwan.
authors.forename: Shiun-Yuan
authors.initials: SY
authors.lastname: Hsu
authors.affiliation: Department of Trauma Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, No.123, Ta-Pei Road, Niao-Sung District, Kaohsiung City, 833 Taiwan.
authors.forename: Hsiao-Yun
authors.initials: HY
authors.lastname: Hsieh
authors.affiliation: Department of Trauma Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, No.123, Ta-Pei Road, Niao-Sung District, Kaohsiung City, 833 Taiwan.
authors.forename: Ching-Hua
authors.initials: CH
authors.lastname: Hsieh
keywords: Fall; In-hospital length of stay; Injury severity score; Mortality; Obesity