Body Mass Index Does Not Predict Injury Pattern or Outcome After Motorcycle Crash

Introduction: The obesity epidemic plagues the United States, affecting approximately 42% of the population. The relationship of obesity with injury severity and outcomes has been poorly studied among motorcycle collisions (MCC). This study aimed to compare injury severity, mortality, injury regions, and hospital and intensive care unit length of stay (LOS) between obese and normal-weight MCC patients.

Methods: Trauma registries from three Pennsylvania Level 1 trauma centers were queried for adult MCC patients (January 1, 2016, and December 31, 2020). Obesity was defined as adult patients with body mass index ≥ 30 kg/m² and normal weight was defined as body mass index < 30 kg/m² but > 18.5 kg/m². Demographics and injury characteristics including injury severity score (ISS), abbreviated injury score, mortality, transfusions and LOS were compared. P ≤ 0.05 was considered significant.

Results: One thousand one hundred sixty-four patients met the inclusion criteria: 40% obese (n = 463) and 60% nonobese (n = 701). Comparison of ISS demonstrated no statistically significant difference between obese and normal-weight patients with median ISS (interquartile range) 9 (5-14) versus 9 (5-14), respectively (P = 0.29). Obese patients were older with median age 45 (32-55) y versus 38 (26-54) y, respectively (P < 0.01). Comorbidities were equally distributed among both groups except for the incidence of hypertension (30 versus 13.8%, P < 0.01) and diabetes (11 versus 4.4%, P < 0.01). There was no statistically significant difference in Trauma Injury Severity Score or abbreviated injury score. Hospital LOS, intensive care unit LOS, and 30-day mortality among both groups were similar.

Conclusions: Obese patients experiencing MCC had no differences in distribution of injury, mortality, or injury severity, mortality, injury regions, and hospital compared to normal-weight adults. Our study differs from current data that obese motorcycle drivers may have different injury characteristics and increased LOS.