Integrating Clinical Judgment and Objective Measures in Normal Pressure Hydrocephalus: Key Predictors of Shunt...

Idiopathic normal pressure hydrocephalus (iNPH) is a neurological disorder affecting older adults for which symptoms may improve following shunting; however, the criteria for surgical referral remain unclear. While most studies rely on fixed cut-off scores for cognitive and gait tests, the present study examined decision-making based on clinical judgment to identify which factors influence referral. A secondary objective was to compare pre- and post-CSF tap test (CSF-TT) changes between the shunt and no shunt groups.

This retrospective study included 175 patients assessed at CHU de Québec - Hôpital de l'Enfant-Jésus. Based on a combination of objective test results and clinical judgment, patients were categorized as referred (n = 119) or not referred (n = 56) for shunt surgery. Logistic regression identified the variables influencing referral decisions. Mixed-effects ANOVA models for repeated measures were conducted to compare pre- and post-CSF-TT changes in gait and cognitive performance between shunt and no shunt groups.

Three change indices significantly predicted referral: the 10-Meter Walk Test (normal pace), the Trail Making Test Condition 5 and the Berg Balance Scale. Higher education positively influenced referral. While most gait and balance measures showed significant improvement following CSF-TT, cognitive tests appeared less responsive to the procedure.

Although this study employed a clinically grounded approach based on clinical judgment rather than fixed thresholds, the findings align with prior literature identifying gait and balance as robust indicators. This study reinforces the need to shift from rigid threshold-based criteria toward individualized, clinically grounded decision-making models that can better capture the heterogeneity of iNPH presentations.