Normal Pressure Hydrocephalus: Clinical Symptom Triad
Normal pressure hydrocephalus presents with a classic triad of gait disturbance, urinary incontinence, and cognitive impairment, with gait abnormalities typically appearing first and cognitive decline developing later in the disease course. 1, 2, 3
Primary Symptoms
Gait Disturbance
- The cardinal and most common presenting symptom is a hypokinetic gait disorder where the feet appear "glued to the floor" or "magnetic," occurring in approximately 70% of NPH patients 2
- The gait is characterized by shuffling, bradykinesia, and an unsteady, broad-based pattern 4, 5
- Gait alterations occur early in the disease course, often before other symptoms become apparent 1, 3
Urinary Incontinence
- Urinary urgency and incontinence develop as part of the classic triad 6, 7
- This symptom may lead patients to initially consult urologists or gynecologists rather than neurologists, contributing to delayed diagnosis 6
Cognitive Impairment
- Cognitive dysfunction develops later in the disease course and is characterized by frontal lobe symptoms including psychomotor slowing, deficits in attention, working memory, verbal fluency, and executive function 3
- Memory lapses occur as part of the subcortical dementia pattern 3, 7
- The cognitive impairment distinguishes NPH from pure motor disorders 8
Clinical Presentation Patterns
Temporal Progression
- Patients typically present late in the disease course due to the slow and gradual nature of symptom onset 1
- The sequence usually follows: gait disturbance → urinary symptoms → cognitive decline 1, 3
Common Pitfalls
- Approximately 80% of NPH cases remain unrecognized and untreated because the symptoms mimic other neurodegenerative disorders 4
- Three-quarters of patients with NPH severe enough to require treatment also suffer from another neurodegenerative disorder (particularly Alzheimer's disease in 20-57% of cases), complicating the clinical picture 3, 9, 4
Diagnostic Significance
- NPH represents a potentially reversible cause of dementia when treated with CSF diversion (shunting), making early recognition critical 1, 3
- The spontaneous course of untreated NPH leads to dependence on nursing care for the vast majority of patients 4
- Modern treatment leads to clinical improvement in 70-90% of properly selected patients, with all three symptoms potentially improving 2, 4