Comorbid Normal Pressure Hydrocephalus with Parkinsonism: A Clinical Challenge and Call for Awareness

Table 2

Comparing signs and symptoms of iNPH versus PD.

	iNPH	PD
Prevalence	2 cases/1000 in individuals > 70; years old [13]	10 cases/1,000 in individuals 70–79; years old [14]
Age at onset	Adults over the age of 60	Incidence peak between 70 and 79 years
Urinary disturbance	Common, nonspecific	Common, nonspecific
Cognitive dysfunction	Frontal, executive dysfunction	Frontal, executive dysfunction; global cognitive impairment usually denotes disease progression
Bradykinesia	62% of patients display bradykinesia affecting their lower limbs symmetrically; upper limbs are typically spared	Cardinal feature of the disease; upper limbs are usually affected early on in an asymmetric fashion
Rest tremor	Absent	Cardinal feature of the disease; observed in about 60% of patients
Rigidity	Rare	Cardinal feature of the disease; observed in about 60% of patients
Hallucinations	Absent	Usually manifesting with visual misperceptions and passage illusions with retained insight; florid hallucinations typically arise in advanced stages
Cortical deficits (aphasia, apraxia, agnosia)	Absent	Rare
Response to L-dopa	Absent, mild, or inconsistent	Excellent, sustained, supportive diagnostic criteria
Response to shunt placement	>60% of patients	Absent
MRI/CT	Ventriculomegaly	Noncontributory
Time course of gait failure	Early feature	If present early, regarded as a “red flag” for the diagnosis of disease
Gait velocity	Decreased	Decreased
Step length	Decreased	Decreased
Arm swing	Normal	Reduced or abolished
Freezing of gait	Early feature	Most commonly observed in the advanced stages
Responsiveness to cues	Absent or poor	Significant
Step height	Reduced	Reduced
Base	Wide	Narrow