Idiopathic normal pressure hydrocephalus (iNPH) is a neurological condition that can cause walking difficulties, cognitive impairment, and urinary incontinence. Although iNPH can be treated with cerebrospinal fluid (CSF) shunt surgery, diagnosis is often challenging because its symptoms and brain imaging findings may overlap with those of other neurodegenerative disorders, such as Alzheimer's disease or vascular parkinsonism. As a result, some patients may experience delayed diagnosis or may not be referred for potentially beneficial surgical treatment.

This observational study aims to evaluate whether combining different types of clinical information can improve the diagnosis of iNPH and help identify patients who are more likely to benefit from surgery. The study integrates cognitive testing, motor performance assessment, CSF biomarker analysis, and brain magnetic resonance imaging.

Patients aged over 60 years with suspected iNPH who are evaluated within a standardized diagnostic care pathway will be included. Cognitive and motor performance will be assessed before and after a cerebrospinal fluid tap test, which is part of routine clinical practice. Results will be compared between patients who receive a confirmed diagnosis of iNPH and undergo CSF shunt surgery and patients who receive an alternative diagnosis and do not undergo surgical treatment.

The results of this study may help improve diagnostic accuracy, reduce false-negative test results, and support better clinical decision-making in patients with suspected idiopathic normal pressure hydrocephalus.

This is an observational, non-interventional cohort study designed to assess the diagnostic and prognostic value of a multimodal approach in patients with suspected idiopathic normal pressure hydrocephalus (iNPH).

The study includes patients aged over 60 years who are referred to a standardized diagnostic, therapeutic, and care pathway for suspected iNPH at a tertiary referral center. All data are collected as part of routine clinical practice after informed consent.

Clinical data collection includes demographic and medical information, standardized neuropsychological assessments, motor performance tests, cerebrospinal fluid (CSF) analysis, and brain magnetic resonance imaging. Cognitive and motor assessments are performed before and after the CSF tap test, which is routinely used to support diagnostic and therapeutic decision-making in iNPH.

The exposed cohort consists of patients with confirmed iNPH who undergo CSF shunt surgery, while the non-exposed cohort includes patients who receive an alternative diagnosis and are managed without surgical intervention. The two groups will be compared with respect to changes in cognitive and motor performance, CSF biomarker profiles, and neuroimaging parameters.

Secondary analyses will explore associations between changes in cognitive and motor outcomes, CSF biomarkers, neuroimaging features, and surgical outcomes, including clinical response at 6 months following surgery when available within the study timeframe.

The study combines prospectively collected data with retrospectively available clinical data to provide a comprehensive characterization of patients with suspected iNPH and to support improved diagnostic accuracy and surgical candidate selection.

Inclusion Criteria:

• Age 60 years or older.
• Patients with suspected idiopathic normal pressure hydrocephalus referred to the institutional diagnostic, therapeutic, and care pathway.
• Ability to provide written informed consent.

Exclusion Criteria:

• Refusal or inability to provide informed consent.

The study population includes adults aged 60 years or older with suspected idiopathic normal pressure hydrocephalus who are referred to a standardized diagnostic, therapeutic, and care pathway at a tertiary referral center. Participants undergo clinical, cognitive, motor, cerebrospinal fluid, and neuroimaging evaluations as part of routine clinical practice.

Individual participant data will not be shared because the study dataset contains sensitive personal health information and, despite de-identification, there remains a risk of re-identification. Data sharing is therefore limited to aggregated results to protect participant privacy and comply with applicable data protection regulations.