Efficacy and Safety of CSF Shunting for Idiopathic Normal Pressure Hydrocephalus: A Systematic Review and Meta-Analysis

Idiopathic normal pressure hydrocephalus (iNPH) is a potentially reversible neurological condition characterized by gait disturbance, cognitive impairment, and urinary dysfunction. CSF shunting remains the standard treatment; however, reported efficacy and complication rates vary across studies. This systematic review and meta-analysis aimed to evaluate the effectiveness and safety of CSF shunting in patients with iNPH based exclusively on evidence from randomized controlled trials (RCTs). The review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Literature searches were performed in PubMed, ScienceDirect, and the Cochrane Library for English-language RCTs published since 2010. Eligible studies included patients aged ≥60 years with radiologically confirmed iNPH who underwent ventriculoperitoneal or lumboperitoneal shunting. Primary outcomes included changes in modified Rankin Scale (mRS) scores and gait velocity. Secondary outcomes included cognitive and urinary measures, as well as adverse events. Random-effects models were applied. Three RCTs comprising 210 participants were included. CSF shunting was associated with significant improvement in functional outcomes (MD, -0.75; 95% CI, -1.01 to -0.49) and gait velocity (MD, 0.21 m/s; 95% CI, 0.12 to 0.29), with low heterogeneity. No significant improvement was observed in cognitive or urinary outcomes. However, shunting was associated with an increased risk of subdural hematoma. CSF shunting provides meaningful functional and gait benefits in carefully selected patients with iNPH, although it is associated with an elevated risk of subdural hematoma. Careful patient selection and risk-benefit evaluation remain essential.