Ventriculoperitoneal shunt placement safety in idiopathic Normal Pressure Hydrocephalus: Anticoagulated versus non-anticoagulated patients

Background Many patients with idiopathic normal pressure hydrocephalus (iNPH) have medical comorbidities requiring anticoagulation that could negatively impact outcomes. This study evaluated the safety of ventriculoperitoneal shunt (VPS) placement in iNPH patients on systemic anticoagulation versus those not on anticoagulation. Methods Patients > 60 years of age with iNPH who underwent shunting between 2018 and 2022 were retrospectively reviewed. Baseline demographics, comorbidities (quantified by modified Frailty Index (mFI) and Charlson Comorbidity Index (CCI)), anticoagulant/antiplatelet agent use (other than aspirin), operative details, and complications were collected. Outcomes of interest were the occurrence of postoperative hemorrhage and overdrainage. Results A total of 234 patients were included in the study (mean age 75.22 ± 6.04 years; 66.7% male); 36 were on anticoagulation/antiplatelet therapy (excluding aspirin). This included 6 on Warfarin, 19 on direct Xa inhibitors, 10 on Clopidogrel, and one on both Clopidogrel and Warfarin. Notably, 70% of patients (164/234) used aspirin alone or combined with anticoagulation or clopidogrel. Baseline mFI was similar between groups, but those on anticoagulant/antiplatelet therapy had a higher mean CCI (2.67±1.87 vs. 1.75±1.84; p=0.001). Patients on anticoagulants were more likely to experience tract hemorrhage (11.1 vs. 2.5%; p=0.03), with no significant difference in the rates of intraventricular hemorrhage or overdrainage related subdural fluid collection. Conclusions Anticoagulant and antiplatelet agents are common in the iNPH population, and patients on these agents experienced higher rates of tract hemorrhage following VPS placement; however, overall hemorrhagic complication rates were similar.