Serum AIM2 as a Prognostic Biomarker for Disease Severity and Delirium in Acute Pancreatitis: A Multicenter Prospective Cohort Study.

OBJECTIVE: Absent in melanoma 2 (AIM2) is implicated in inflammation, and delirium is a common complication following acute pancreatitis (AP). We investigated whether serum AIM2 levels are related to severity and delirium after AP. METHODS: This multicenter prospective cohort study included 349 patients with AP and 100 controls. According to a ratio of 7:3, patients were randomly assigned to study group (244 cases) and validation group (105 cases). Severity metrics included the acute physiologic and chronic health evaluation II (APACHE II), Ranson scale, computed tomography severity index (CTSI), and bedside index for severity in acute pancreatitis (BISAP). Severity correlation and delirium association were determined by using multifactorial analyses. Delirium-prediction model was verified in the validation group. RESULTS: Serum AIM2 levels were significantly higher in patients with AP than in controls. Serum AIM2 levels were independently correlated with the APACHE II scores, Ranson scores, BISAP scores, and CTSI scores. Serum AIM2 levels were linearly related to delirium risk after AP under the restricted cubic spline. Serum AIM2 levels, CTSI scores and BISAP scores were independently associated with delirium following AP. Serum AIM2 levels had predictive ability comparable to those of APACHE II, Ranson, BISAP, and CTSI scores. Delirium-prediction model integrating serum AIM2 levels, CTSI scores, and BISAP scores was stable and clinically valid by using a series of statistical approaches, whether in the study group or validation group. CONCLUSIONS: Enhanced serum AIM2 levels are tightly correlated with disease severity and efficiently predict delirium following AP, suggesting that serum AIM2 may be a potential biomarker of AP.