Early Plasmapheresis Among Patients With Hypertriglyceridemia-Associated Acute Pancreatitis.

Importance: The incidence of hypertriglyceridemia-associated acute pancreatitis (HTG-AP) is increasing. Plasmapheresis is theoretically effective in removing triglyceride from plasma, but whether it confers clinical benefits is unclear. Objective: To assess the association between plasmapheresis and the incidence and duration of organ failure among patients with HTG-AP. Design, Setting, and Participants: This is an a priori analysis of data from a multicenter, prospective cohort study with patients enrolled from 28 sites across China. Patients with HTG-AP were admitted within 72 hours from the disease onset. The first patient was enrolled on November 7th, 2020, and the last on November 30th, 2021. The follow-up of the 300th patient was completed on January 30th, 2022. Data were analyzed from April to May 2022. Exposures: Receiving plasmapheresis. The choice of triglyceride-lowering therapies was at the discretion of the treating physicians. Main Outcomes and Measures: The primary outcome was organ failure-free days to 14 days of enrollment. Secondary outcomes included other measures for organ failure, intensive care unit (ICU) admission, duration of ICU and hospital stays, incidence of infected pancreatic necrosis, and 60-day mortality. Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) analyses were used to control potential confounders. Results: Overall, 267 patients with HTG-AP were enrolled (185 [69.3%] were male; median [IQR] age, 37 [31-43] years), among whom 211 underwent conventional medical treatment and 56 underwent plasmapheresis. PSM created 47 pairs of patients with balanced baseline characteristics. In the matched cohort, no difference was detected concerning organ failure-free days between patients undergoing plasmapheresis or not (median [IQR], 12.0 [8.0-14.0] vs 13.0 [8.0-14.0]; P = .94). Moreover, more patients in the plasmapheresis group required ICU admission (44 [93.6%] vs 24 [51.1%]; P < .001). The IPTW results conformed to the results from the PSM analysis. Conclusions and Relevance: In this large multicenter cohort study of patients with HTG-AP, plasmapheresis was commonly used to lower plasma triglyceride. However, after adjusting for confounders, plasmapheresis was not associated with the incidence and duration of organ failure, but with increased ICU requirements.