BACKGROUND:Hypertriglyceridemia is one of the three most common causes of AP, which is associated with the AP prognosis that has not been clearly defined. METHODS:In this retrospective study, 1539 AP patients, who had serum triglyceride (TG) levels measured within the first 72 h, were assessed. The study groups consisted of patients with normal, mild, moderate, and severe/very severe HTG levels based on the Endocrine Society Clinical Practice Guidelines. We collected baseline demographic information, laboratory values, complications, and clinical outcome data in different HTG severity groups to analyze the clinical significance of elevated TG levels in AP. RESULTS:Our study included 1539 AP patients; of these, 1078 (70%) had a normal TG levels, and 461 (30%) had elevated TG levels. The rates of severe AP increased in HTG groups of increasing severity (4% vs. 8% vs. 12%; P trend < 0.001). acute necrotic collection (ANC) and pancreatic necrosis developed in 32 and 39 of 112 patients (29% and 35%) (P trend = 0.001; P trend = 0.001) in the severe/very severe HTG group, respectively. The proportion of persistent organ failure (POF), multiple organ failure (MOF), and persistent Systemic Inflammatory Response Syndrome (SIRS) increased with higher grades of HTG (P trend < 0.001; P trend < 0.001; P trend < 0.001). The ICU admission rate was higher in the severe/very severe HTG group (57/112 patients; 51%; P trend < 0.001). A logistic multivariate regression analysis showed a positive correlation between HTG and certain AP complications. CONCLUSION:In addition to other factors, an elevated TG level could be associated with the severity and prognosis of AP, including pancreatic necrosis, POF, MOF, persistent SIRS, ICU admission, and mortality.