Total Psoas Area Index is Valuable to Assess Sarcopenia, Sarcopenic Overweight/Obesity and Predict Outcomes in Patients Undergoing Open Pancreatoduodenectomy

Background and Aim Sarcopenia has been proven to be a risk factor after pancreatoduodenectomy (PD). We aimed to evaluate if decreased psoas muscle area and density shown in CT scan, as measures for sarcopenia, were associated with postoperative major complications and adverse outcomes in patients who underwent PD. Patients and Methods We analyzed 152 consecutive patients who underwent open PD. Total psoas area and muscle attenuation were measured on CT images at the level of the third lumbar vertebra. Total psoas area index (TPAI) was calculated, the cut-off values of TPAI were estimated and validated. The relationship between radiographic characters and outcomes was analyzed. Results The optimal cut-off values of TPAI were 4.78 cm2/m2 for males and 3.46 cm2/m2 for females. The values were validated by outcomes with significant differences in the rate of major complications, re-operation, length of stay, and total cost. The prevalence of TPAI-defined sarcopenia and sarcopenic overweight/obesity was 38.8% and 17.1% in total. In multivariate logistic regression, rate of major complications was associated with TPAI [OR=0.605, 95% CI (0.414, 0.883), P=0.009], TPAI-defined sarcopenia [OR=8.256, 95% CI (2.890, 23.583), P=0.000] and sarcopenic overweight/obesity [OR=7.462, 95% CI (2.084, 26.724), P=0.002]; meanwhile, NRS2002-defined nutritional risk and GLIM-defined malnutrition did not show relationship with major complications. Conclusion Both sarcopenia and sarcopenic overweight/obesity determined by new TPAI cut-off values were associated with a higher rate of major complications and adverse outcomes in Chinese patients undergoing open PD whereas usual nutritional assessment was not.