ObjectiveTo investigate the features of patients with recurrence of hypertriglyceridemic acute pancreatitis (HTG-AP) and the influence of metabolic syndrome (MetS) on recurrence through a retrospective analysis. MethodsA retrospective analysis was performed for 132 patients with recurrent HTG-AP who were admitted to The Affiliated Hospital of Southwest Medical University from June 2013 to December(recurrence group), and 132 patients with non-recurrent HTG-AP who were treated during the same period of time were enrolled as control group. Related data were collected, including basic information (age, sex, diabetes, hypertension, and body mass index), clinical data (etiology, routine blood test results, and biochemical results), and complications ［systemic inflammatory response syndrome (SIRS), acute peripancreatic fluid collection (APFC), acute necrosis collection (ANC), acute respiratory distress syndrome (ARDS), acute renal failure (ARF), multiple organ dysfunction syndrome (MODS), and ICU admission rate］. The t-test was used for comparison of normally distributed continuous data between groups, and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between groups; the chi-square test or the Fisher’s exact test was used for comparison of categorical data between groups. A logistic regression analysis was used for comparison of related variables, and the receiver operating characteristic (ROC) curve was used to validate the diagnostic value of variables. ResultsCompared with the control group, the recurrence group had a significantly higher proportion of patients with MetS, obesity, a high-density lipoprotein cholesterol (HDL-C) level of ＜1 mmol/L, or ANC and significantly higher levels of blood glucose and C-reactive protein (CRP) and white blood cell count (WBC) (χ2=9.138, χ2=6.823, χ2=13.251, χ2=9587, Z=-2.255, Z=-2.202, Z=-4.674, all P＜0.05). The 132 patients in the recurrence group were divided into MetS group with 92 patients and non-MetS group with 40 patients, and compared with the non-MetS group, the MetS group had significantly higher WBC and blood glucose and a significantly higher proportion of patients with SIRS, APFC, ANC, or progression to moderate-to-severe AP (MSAP) (t=2.434, t=4.881, χ2=4.513, χ2=7.936, χ2=7.031, χ2=7.150, all P＜0.05). MetS (odds ratio ［OR］=2.007, 95% confidence interval ［CI］: 1.152-3.497, P＜0.05), ANC (OR=2.270, 95%CI: 1.185-4.347, P＜0.05), and WBC (OR=1.135, 95%CI: 1.059-1.217, P＜0.05) were independent risk factors for recurrence in HTG-AP patients. The combination of MetS, ANC, and WBC had a relatively high value in predicting the recurrence of HTG-AP, with an area under the ROC curve of 0.692. In the recurrence group, the levels of triglyceride, blood glucose, and CRP and the proportion of patients with smoking, HDL-C ＜1 mmol/L, or obesity in 125 patients (7 patients were excluded due to incomplete case data) at the time of recurrence were significantly lower than those in 132 patients at initial admission (Z=-3.270,Z=-3.546,Z=-4.382,χ2=0547,χ2=8.259,χ2=5.143, all P＜0.05), with further reductions in the proportion of patients with MSAP, APFC, or ANC (χ2=4.086,χ2=11.930,χ2=4.967,all P＜005). ConclusionMetS aggravates disease severity in patients with recurrent HTG-AP and is an important factor for recurrence. Smoking cessation, weight loss, and oral lipid-lowering drugs can reduce disease severity at the time of readmission.