Obesity classification predicts early complications and mortality after acetabular fracture

Obesity remains a global epidemic. The effect of obesity on the risk of complications after acetabular fracture is unknown. Here, we evaluate the effect of BMI on early complications and mortality after acetabular fracture. We hypothesize that the risk of inpatient complications and mortality will be greater in patients with high BMI when compared to those with normal BMI.

Adult patients with acetabular fracture were identified via the Trauma Quality Improvement Program data from 2015 to 2019. The primary outcome was overall complication rate with reference to normal-weight patients (BMI = 25-30 kg/m²). The secondary outcome was rates of death. The association of obesity class on the primary and secondary outcomes was assessed using Bonferroni-corrected multiple logistic regression models considering patient, injury, and treatment covariates.

A total of 99,721 patients with acetabular fracture were identified. Class I obesity (BMI = 30-35 kg/m²) was associated with 1.2 greater adjusted relative risk (aRR; 95% confidence interval (CI) 1.1-1.3) of any adverse event, without significant increases in adjusted risk of death. Class II obesity (BMI = 35-40 kg/m²) was associated with aRR = 1.2 (95% CI 1.1-1.3) of any adverse event and aRR = 1.5 (95% CI 1.2-2.0) of death. Class III obesity (BMI ≥ 40 kg/m²) was associated with aRR = 1.3 (95% CI 1.2-1.4) of any adverse event and aRR = 2.3 (95% CI 1.8-2.9) of death.

Obesity is associated greater risk of adverse events and death following acetabular fracture. Obesity severity classification scales with these risks.