From the Guidelines
Progressive supranuclear palsy (PSP) is a rare neurodegenerative brain disorder characterized by the gradual deterioration of brain cells in areas that control movement, balance, speech, swallowing, vision, mood, behavior, and cognition, with a hallmark symptom of difficulty with eye movements, especially looking downward. PSP is a tauopathy, in which tau proteins abnormally accumulate in different regions of the brain, forming tangles that disrupt normal cellular function 1. The condition typically begins after age 60 and progresses more rapidly than Parkinson's disease, with which it is often initially confused. Other common symptoms include:
- Frequent falls (often backward)
- Stiffness
- Slow movement
- Difficulty swallowing
- Slurred speech
- Changes in personality or cognition PSP is the most common atypical Parkinsonism, with a prevalence of around 5/100,000, and patients classically present in the sixth or seventh decade (mean age of onset at 63) with a lurching gait and axial dystonia, manifested as unexplained falls 1.
Diagnosis and Treatment
Diagnosing PSP can be challenging, and imaging remains an essential diagnostic tool in the evaluation of a patient presenting with Parkinsonian symptoms 1. The neurological examination aims to identify motor signs that may be associated with PSP, such as parkinsonism, oculomotor disorders, or vertical gaze palsy (or in early stages, absence of normal optokinetic nystagmus or slowing of down saccades) and postural instability 1. Currently, there is no cure for PSP, and treatment focuses on managing symptoms with medications like levodopa (though response is typically limited), antidepressants for mood symptoms, and botulinum toxin for eye problems. Physical, occupational, and speech therapy are crucial parts of management. Most patients require increasing assistance with daily activities as the disease progresses, with life expectancy typically 5-9 years after diagnosis.
From the Research
Definition and Characteristics of Progressive Supranuclear Palsy
- Progressive supranuclear palsy (PSP) is a progressive neurodegenerative disorder characterized by postural instability and falls, vertical supranuclear gaze palsy, parkinsonism with poor levodopa response, pseudobulbar palsy, and frontal release signs 2.
- PSP is a disorder of tau protein aggregation, with a clinical spectrum wider than originally described, including a phenotype resembling Parkinson disease 3.
- The disease is almost entirely sporadic, with a prevalence of five to six persons per 100,000, mean onset age of 63, and median survival of 7 years 3.
Clinical Features and Diagnosis
- The most commonly reported symptoms at baseline are motor (100%) followed by cognitive/behavioral (89%), systemic and bulbar (80%), and sleep disturbances (60%) 2.
- Slowness of movement, falls, neck stiffness, and difficulty looking up/down have high prevalence from baseline, while balance and gait impairment are less common at baseline but increase in prevalence over time 2.
- The 2017 International Parkinson and Movement Disorder Society PSP criteria outline 14 core clinical features and 4 clinical clues that combine to diagnose one of eight PSP phenotypes with probable, possible, or suggestive certainty 4.
Treatment and Management
- Current treatment is symptomatic, but tau-based therapeutics are in active clinical trials 4.
- Deep brain stimulation (DBS) has been explored as a possible symptomatic treatment for PSP, considering the pedunculopontine nucleus (PPN) as a promising target, but current evidence does not yet establish clear criteria for ideal candidates 5.
- Carefully targeted symptomatic treatment with drugs and other therapies is available and effective at reducing morbidity and improving quality of life 6.