Effectiveness and safety of low molecular weight heparin in the management of acute pancreatitis: a systematic review and meta-analysis

Background Recent studies suggest that low-molecular-weight heparin (LMWH) may play a role in mitigating the severity of acute pancreatitis (AP). This systematic review and meta-analysis aims to synthesise existing evidence on the effectiveness and safety of LMWH in the treatment of moderately-severe and severe AP. Methods This systematic review and meta-analysis was conducted in accordance with the 2020 update of the PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. The systematic search was conducted in MEDLINE, the Cochrane Central Register of Controlled Trials, Scopus, and EMBASE, covering studies published up to February 2024. Randomised controlled trials (RCTs) and observational studies (n-RCTs) that reported the differences in the outcomes of AP for patients receiving LMWH in addition to the standard treatment (Intervention), compared to patients managed by standard treatment without LMWH (Control) were eligible. A random-effects model was used to calculate the pooled relative risk (RR) and mean differences (MD) with the corresponding 95% CI. Results Thirteen studies were included in the meta-analysis, all published between 2004 and 2022. Eight studies were RCTs, and five were n-RCTs. Data from 13,709 patients (6.971 Interventions and 6.738 Controls) were analysed. The comparison of Intervention and Control groups showed the superiority of LMWH to standard treatments in terms of overall mortality (RR = 0.44, 95% CI = 0.31; 0.64, P < 0.0001, I2 = 51%), acute necrotic collections (RR = 0.24, 95% CI = 0.09; 0.62, P = 0.003, I-2 = 0%), and organ failure (RR = 0.67, 95% CI = 0.48; 0.93, P = 0.02, I-2 = 78%). The Intervention group showed superior outcomes compared with the Control group for gastrointestinal bleeding (RR = 0.64, 95% CI = 0.44; 0.94, P = 0.02, I-2 = 0%), length of hospital stay (MD= - 6.08, 95% CI = - 10.08; - 2.07, P = 0.003, I-2 = 98%), need for operative interventions (RR = 0.50, 95% CI = 0.29; 0.87, P = 0.01, I-2 = 61%), and vascular thrombosis (RR = 0.43, 95% CI = 0.31; 0.61, P < 0.00001, I-2 = 0%). Conclusions Moderate to high-quality evidence suggests that early intervention with LMWH could improve the prognosis of non-mild AP in terms of mortality, organ failure, and decreased incidence of vascular thrombosis. In light of our findings, integrating LMWH into the treatment regimen for moderate-severe to severe AP is advocated.