Effectiveness of acrylonitrile-co-methallyl sulfonate surface-treated membranes for treating pneumonia: A propensity-score matched retrospective cohort study

Abstract Background: The acrylonitrile-co-methallyl sulfonate surface-treated (AN69ST) membrane has cytokine adsorption capacity and is used for treating sepsis. This study aimed to compare the effects of continuous renal replacement therapy (CRRT) using the AN69ST membrane with CRRT using other membranes for patients with pneumonia-associated sepsis.Methods: We conducted a retrospective cohort study using a nationwide Japanese inpatient database. We included data of those adults who were hospitalized with a primary diagnosis of pneumonia and received CRRT using either the AN69ST membrane or another membrane within 2 days of admission and were discharged from the hospitals between September 2014 and March 2017. Propensity-score matching was used to compare in-hospital mortality between the two groups.Results: Eligible patients (N = 2,393) were categorized into an AN69ST group (N = 631) and a non-AN69ST group (N = 1,762). The overall in-hospital mortality rate was 38.9%. Among the 545 propensity-matched patient pairs, the in-hospital mortality rate was significantly lower in the AN69ST group than in the non-AN69ST group (35.8 vs. 41.8%, P = 0.046).Conclusions: Among patients with pneumonia-associated sepsis treated with CRRT, CRRT with the AN69ST membrane was associated with a significantly lower in-hospital mortality than CRRT with standard membranes.