Aims: We studied the role of obesity and the Acute Physiology and Chronic Health Evaluation (APACHE) O score in predicting the outcome in patients with acute pancreatitis (AP) using the Asia-Pacific obesity classification.
Methods: Two hundred eighty AP patients were classified into three different groups, normal weight [body mass index (BMI) = 18.5-22.9 kg/m(2)], overweight (BMI = 23-24.9 kg/m(2)) and obese (BMI > 25 kg/m(2)), according to the Asia-Pacific obesity classification. For all patients APACHE II scores and modified APACHE O (i.e., APACHE Oap) scores that included a factor for obesity were calculated. The patients were managed using a standard protocol, and the outcome measures were compared for different obesity groups.
Results: Of the 280 patients (mean age 40.7 years), 46.8% were normal weight, 29.6% overweight and 23.6% obese. Forty-six (16.4%) patients underwent surgery, and 61 (21.8%) patients died. Patients with higher BMI had worse radiological indices of severity, more infected necrosis (p < 0.001), more persistent organ failure (p < 0.001) and higher requirement for percutaneous drain insertion (p = 0.04), surgery (p = 0.008) and mortality (p < 0.001). The area under the curve for predicting mortality was 0.879 for APACHE II and 0.886 for APACHE Oap; at a cutoff of 8.5, the APACHE II score had a sensitivity of 88.2% and specificity of 68.7%, and APACHE Oap 90.2 and 64.0%, respectively.
Conclusions: BMI ≥ 23 kg/m(2) was an important predictor of a severe disease course and fatal outcome in patients with AP. However, the predictive accuracy of APACHE Oap for mortality was similar to APACHE II.