- Progressive supranuclear palsy (PSP) is a rare, progressive neurodegenerative disease that affects movement, balance, vision, speech, and cognition. It is classified as a tauopathy, meaning it is caused by abnormal accumulation of the tau protein in specific areas of the brain, particularly the brainstem, basal ganglia, and frontal lobes. PSP typically begins in people over the age of 60 and progresses over several years.
- The hallmark symptoms of PSP are postural instability and early falls, especially falling backward, often within the first year of onset. Patients may also develop supranuclear gaze palsy, which refers to difficulty moving the eyes, especially vertically (looking up and down), despite intact eye muscles. This eye movement problem often leads to visual disturbances and difficulty with tasks such as reading or going down stairs. In addition to these core features, patients commonly experience stiffness, slowness of movement (bradykinesia), and axial rigidity (trunk stiffness more than limb stiffness), which can resemble Parkinson’s disease, although PSP typically does not respond well to dopaminergic treatments like levodopa.
- Cognitive and behavioral symptoms are also common in PSP. These may include executive dysfunction (difficulty with planning, problem-solving, and multitasking), apathy, impulsivity, and emotional lability. Unlike Alzheimer’s disease, memory may be relatively preserved in early stages. Speech and swallowing difficulties (dysarthria and dysphagia) often arise as the disease progresses, contributing significantly to disability and risk of aspiration pneumonia.
- The cause of PSP is not fully understood, but it is associated with the accumulation of abnormal 4R tau isoforms in affected brain regions. This tau pathology leads to neuronal loss and gliosis. Although most cases are sporadic, rare familial cases linked to mutations in the MAPT gene have been reported. PSP is part of a broader spectrum of disorders called atypical parkinsonian syndromes, which also includes corticobasal degeneration (CBD) and multiple system atrophy (MSA).
- Diagnosis of PSP is based on clinical criteria and supported by neuroimaging. MRI may reveal midbrain atrophy with preservation of the pons, leading to the classic “hummingbird” or “penguin” sign on sagittal views. Functional imaging or PET scans may assist in distinguishing PSP from Parkinson’s disease or other parkinsonian disorders. However, no definitive diagnostic test exists, and diagnosis often evolves over time.
- There is currently no cure for PSP, and treatment focuses on symptom relief and supportive care. Physical therapy and balance training can help manage mobility issues and reduce the risk of falls. Speech and occupational therapy may assist with communication and daily living activities. Dopaminergic medications like levodopa are sometimes tried but generally provide limited benefit. As the disease advances, multidisciplinary care becomes essential, involving neurologists, rehabilitation specialists, speech therapists, and caregivers.
- Research into PSP is ongoing, particularly in understanding tau pathology and developing targeted therapies. Clinical trials are exploring anti-tau agents and neuroprotective strategies. Increased awareness and earlier recognition of PSP can improve management and quality of life for patients and families dealing with this challenging condition.
