Background Systemic immune-inflammation index (SII) has been identified as a prognostic biomarker in various diseases. However, its significance in acute pancreatitis (AP) has not been reported. Therefore, the main aim of this study was to determine the association of SII with clinical outcomes of AP patients, after adjusting for several confounders. Methods This retrospective cohort study was conducted using data retrieved from the Medical Information Mart for Intensive Care III database (MIMIC-III). The study only included patients diagnosed with AP. SII was calculated as the platelet counts x neutrophil counts/lymphocyte counts. Cox regression models were employed to assess the impact of SII on the 30- and 90-day mortality of AP patients. Subgroup analysis was carried out to explore the stability of the relationship between SII and AP mortality. Results A total of 513 patients were found to be eligible based on the inclusion and exclusion criteria. For 30-day all-cause mortality, in the model adjusted for multiple confounders, the HR (95% CI) for mid-SII group (SII: 75.6−104.2) and high-SII groups (SII: >104.2) were 1.29 (0.65, 2.56) and 2.57 (1.35, 4.88), respectively, compared to the low-SII group (SII: <75.5). A similar trend was observed for 90-day mortality. Subgroup analyses presented a stable relationship between SII and 30-day all-cause mortality of AP patients. Conclusion SII is a potentially useful prognostic biomarker for AP. However, prospective studies are needed to confirm this finding.

Background The association of serum triglyceride (TG) levels with the severity of hypertriglyceridaemia-induced acute pancreatitis (HTG-AP) remains controversial. This study aimed to comprehensively assess the TG levels from the initial onset and their predictive value in the disease assessment of HTG-AP. Methods Data collected from January 2018 to July 2021 in one institute were assessed retrospectively. HTG-AP was defined as a TG level > 500 mg/dL in the absence of other common aetiologies of AP. The TG levels within 24 hours (24 h), 48 hours (48 h), 3-4 days (3-4 d), and 5-7 days (5-7 d) after symptom onset and their correlations with disease severity in HTG-AP patients were analysed by cross-sectional and longitudinal studies. Results In the cross-sectional study, 377 HTG-AP patients were included before lipid-lowering intervention: 216 subjects had their first TG levels measured within 24 h after onset, 91 within 48 h, 50 in 3-4 d, and 20 in 5-7 d. TG levels decreased in the 24 h, 48 h and 3-4 d groups (P < 0.001), however, the TG decline in the 5-7 d group had no difference compared with the 3-4 d group. HTG-AP patients with severe or moderately severe disease displayed higher TG levels than those with mild disease in the 24 h and 48 h groups (P < 0.050) but not in the 3-4 d or 5-7 d groups. Furthermore, the TG levels were correlated with the modified computed tomography severity index only in the 24 h and 48 h groups, while an association between serum calcium levels and C-reactive protein levels was only present in the 24 h group. Similarly, the TG levels were related to hospital days and ICU days in the 24 h and/or 48 h groups. In the longitudinal study, 165 patients with complete records of TG levels from 24 h to 5-7 d were enrolled. With supportive care and lipid-lowering treatment after admission, the TG levels declined rapidly (P < 0.001), and the correlations with disease severity weakened or even disappeared from 24 h to 5-7 d. Conclusion TG levels decreased and attenuated the association with disease severity of HTG-AP over the time of onset. The TG levels within the initial 48 h after onset were most useful for the diagnosis and disease assessment of HTG-AP.