Subcutaneous adipose tissue is associated with acute kidney injury after abdominal trauma based on the generalized propensity score approach: A retrospective cohort study.

INTRODUCTION: Obesity is associated with an increased risk of acute kidney injury (AKI) after trauma. However, the associations between different adipose tissue depots and AKI remain unknown. Our study aims to quantify the effect of abdominal adiposity on AKI in trauma patients.

METHODS: We performed a retrospective cohort study of abdominal trauma patients who were admitted into our hospital from January 2010 to March 2020. Abdominal VAT (visceral adipose tissue) and SAT (subcutaneous adipose tissue) were measured at the level of the third lumbar vertebra using computed tomography. Causal modeling based on the generalized propensity score was used to quantify the effects of BMI (body mass index), VAT and SAT on AKI.

RESULTS: Among 324 abdominal trauma patients, 67 (20.68%) patients developed AKI. Patients with AKI had higher BMI (22.46 kg/m2 vs. 22.04 kg/m2, P = 0.014), higher SAT areas (89.06 cm2 vs. 83.39 cm2, P = 0.151) and VAT areas (140.02 cm2 vs. 91.48 cm2, P = 0.001) than those without AKI. By using causal modeling, we found that the risk of developing AKI increased by 8.3% (P = 0.001) and 4.8% (P = 0.022) with one unit increase in BMI (per 1 kg/m2), and ten units increase in SAT (per 10 cm2), respectively. However, VAT did not show a significant association with AKI (P = 0.327).

CONCLUSION: SAT, but not VAT, increased the risk of AKI among abdominal trauma patients. Measurement of SAT might help to identify patients at higher risk of AKI.