Symptoms of Progressive Supranuclear Palsy
Progressive supranuclear palsy (PSP) is characterized primarily by vertical supranuclear gaze palsy, postural instability with frequent backward falls, axial dystonia, and parkinsonian features that respond poorly to levodopa treatment. 1
Core Clinical Features
Movement and Postural Symptoms
- Postural instability and falls: Early and prominent symptom, with patients often falling backward 1, 2
- Parkinsonian features:
- Bradykinesia/akinesia (slowness of movement)
- Rigidity (particularly axial/neck stiffness)
- Parkinsonian gait/posture
- Notable absence or minimal presence of tremor compared to Parkinson's disease 1
- Lurching gait and axial dystonia 1
Ocular Symptoms
- Vertical supranuclear gaze palsy: Difficulty looking up and down, particularly downward gaze 1, 3
- Early ocular symptoms that may precede full gaze palsy:
- Decreased velocity of saccades
- Slow saccades
- Absence of normal optokinetic nystagmus vertically 1
- Fixation instability 3
- Eyelid abnormalities:
- Lid retraction
- Blepharospasm
- Apraxia of eyelid opening and closing 3
Cognitive and Behavioral Symptoms
- Cognitive impairment: Present in early stages and progressive 4
- Frontal release signs 2
- Pseudobulbar palsy: Emotional lability, inappropriate laughing or crying 2
Bulbar Symptoms
- Dysarthria: Speech difficulties
- Dysphagia: Swallowing difficulties (more common in later stages) 4
Progression Pattern
Early Symptoms (First 2-3 Years)
- Gait disorders and unexplained falls (particularly backward)
- Slowness of movement
- Neck stiffness
- Difficulty looking up/down
- Cognitive changes 2, 4
Later Symptoms (After 4+ Years)
- Progressive loss of independence in activities of daily living
- Worsening dysphagia
- More severe ocular and cognitive disorders
- Sleep disturbances (associated with increased mortality risk) 2, 4
Diagnostic Challenges
- PSP can be difficult to diagnose, especially in early stages when vertical gaze palsy may not be present 5
- Can be confused with other parkinsonian disorders like Parkinson's disease, multiple system atrophy, dementia with Lewy bodies, and corticobasal degeneration 3
- Some patients may present with PSP-like symptoms (vertical supranuclear gaze palsy, postural instability) but without parkinsonism 6
Key Distinguishing Features from Parkinson's Disease
- Poor response to levodopa therapy 5
- Early falls and postural instability (vs. later in Parkinson's)
- Vertical gaze abnormalities (vs. normal in early Parkinson's)
- Less tremor than typical Parkinson's disease
- More rapid progression 1, 5
Imaging studies, while not specific for PSP, may assist in diagnosis, but the definitive diagnosis requires both clinical and neuropathological evidence 5.
The average age of onset is around 63-65 years, with a median survival of approximately 9 years from symptom onset 5, 2.
PSP symptoms significantly impact quality of life and functional independence, with most patients requiring assistance with daily activities after 4 years of disease progression 4.