A Screening Protocol for Idiopathic Normal Pressure Hydrocephalus: Reducing Underdiagnosis, Relieving the Economic Burden for the Health Systems, while Improving the Quality of Life of our Patients

Abstract

Background

Idiopathic normal pressure hydrocephalus (iNPH) is a common condition affecting the elderly. Numerous investigations highlight that its period-prevalence could be underestimated, as well as the economic burden of the missed treatments. The objective of the present investigation is to determine if a cohort of radiologically suspected iNPH patients presents the clinical landmarks of this condition, and to estimate the economic burden of these potentially missed diagnoses.

Methods

We recorded age, sex, reason to access emergency rooms of our community hospitals, values of Evans' Index, callosal Angle, presence of disproportionately enlarged subarachnoid space hydrocephalus and obvious ventricular enlargement. We telephoned the patients who presented at least two radiological signs of iNPH and administered the idiopathic normal-pressure hydrocephalus grading scale (iNPHGS), to assess the severity of signs and symptoms linked to iNPH, to understand if a strong radiological suspect had a clinical correlation.

Results

Among the 308 brain computed tomography scans of a week, a total of 21 agreed to be enrolled in the present investigation. When administering iNPHGS questionnaire to radiologically suspected iNPH, 17/21 patients (80.1%) scored ≥1 in at least two of the three iNPHGS subscales. The scores of the three subscales were strongly associated to each other. The estimated monthly and yearly health-related costs may be EUR 4'799'440 and 57.59 million of Euros, respectively.

Conclusions

There is an association between the radiological features of iNPH and the scores of iNPHGS. The period-prevalence could be 5.51%, implying high health care costs, with significant societal impact, and reduced quality of life in patients suffering from undiagnosed iNPH.

Keywords

iNPH - cognitive - urinary - gait disturbance - costs

Institutional Review Board Statement

Ethics committee/institutional review board approval was not required for this manuscript, because it was a retrospective, observational data collection, without any randomization, The radiological and clinical data, and the analyzed data were completely anonymized. The study did not influence world wide accepted standard of care. All included patients signed a formal informed consent after appropriate information, both for letting the data be analyzed in research and concerning surgical information.

Data Availability Statement

Data available on request, [e-mail], [e-mail]

Author Contributions

G.P. ideation, S.C. and E.I. data collection. An.Po. and M.S. methodology and supervision. A.Pe., D.A., and G.D.M. manuscript draft and revision. A.P. final supervision.

Publication History

Received: 04 September 2024

Accepted: 04 July 2025

Accepted Manuscript online:
07 July 2025

Article published online:
09 January 2026

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