The Impact of Lipoprotein Apheresis on Changes of Fibrinogen and aPTT: A Systematic Review and Meta-Analysis

Lipoprotein apheresis (LA) may influence hemostasis, but reported effects are inconsistent. We quantitatively assessed changes in fibrinogen, plasminogen, activated partial thromboplastin time (aPTT) and thrombin time (TT). Following PRISMA, PubMed, Scopus, and Web of Science were searched to August 2025 for observational human studies reporting pre-/post-apheresis values. Weighted mean differences (WMD) with 95% confidence intervals (CIs) were pooled using random- or fixed-effects models according to heterogeneity. Prespecified subgroups compared modality (DALI, HELP) and treatment duration (≤ 1 year, > 1 year). Meta-regression, publication bias and leave-one-out sensitivity analyses were performed. From 678 records, 38 publications were eligible. LA reduced fibrinogen (60 studies; n = 1615; WMD = -107.46 mg/dL, 95% CI: -125.3 to -89.63; p < 0.001) and prolonged aPTT (14 studies; n = 406; WMD = +47.9 s, 95% CI: 34.29-61.51; p < 0.001). No significant change was observed for plasminogen (5 studies; n = 171; WMD = -1.89 mg/dL, 95% CI: -5.14 to 1.36; p = 0.29) or TT (4 studies; n = 54; WMD = +2.56 s, 95% CI: -0.25 to 5.37; p = 0.59). Fibrinogen fell with both modalities and durations, greater with HELP (-139.13 mg/dL) than DALI (-58.9 mg/dL). aPTT increased with both, numerically larger with DALI (+90.21 s) than with HELP (+26.95 s). Repeated LA lowers fibrinogen and prolongs aPTT, with no clear pooled effect on plasminogen or TT. These findings support routine periprocedural coagulation monitoring and standardized reporting across modalities.