Under the Umbrella -- Progressive Supranuclear Palsy
Overview
Progressive supranuclear palsy (PSP) is a rare brain disorder that causes serious and permanent problems with control of gait and balance. The hallmark of PSP is a visual disturbance, which results from a progressive inability to coordinate eye movements, and is the cause of instability. Additional motor symptoms similar to those seen in Parkinson disease, such as tremor (involuntary shaking) and rigidity (resistance to imposed movement) usually develop. Depression and apathy are common mood symptoms. Later in disease progression, other FTD features such as behavioral and social dysfunction or cognitive decline, may develop. PSP is not itself life-threatening. If medical complications do not develop, patients may live into their 70's.
Key Clinical Features
* Difficulty coordinating eye movement This is the hallmark of PSP, the symptom that usually develops first, and the feature that is most useful in distinguishing PSP from similar neurodegenerative disorders (such as Parkinson). Patients cannot coordinate their eyes to look up or down. Some patients experience this visual deficit as blurring.
* Gait instability results from a decreasing ability to maintain balance.
* Slowness and stiffness of movements, similar to that seen in Parkinson disease
* Dysphagia (difficulty swallowing)
* Dysarthria (speech difficulties)
* Alterations in mood and behavior may include depression and apathy.
Later in the disease progression some PSP patients experience symptoms in the following categories:
* Behavioral Symptoms
* Cognitive Symptoms
* Emotional Symptoms
Key Pathologic Features
Upon autopsy, there is atrophy of cells in the basal ganglia, the substantia nigra, the subthalamus, and the brainstem (the portion of the brain responsible for balance). These areas also suffer neuronal loss and gliosis (overgrowth, or development of tumors). Lesions in the portion of the brain called the oculomotor nucleus, which is responsible for coordinating eye movements, are also found.
Cause
Scientists have recently determined that these affected cells contain deposits of an abnormal form of the protein tau.
Genetics
The majority of PSP is not hereditary.
Treatment
There is currently no effective treatment for PSP, although scientists are searching for better ways to manage the disease. In some patients the slowness, stiffness, and balance problems of PSP may respond to antiparkinsonian agents such as levodopa, or levodopa combined with anticholinergic agents, but the effect is usually temporary. The speech, vision, and swallowing difficulties usually do not respond to any drug treatment.
Another group of drugs that has been of some modest success in PSP are antidepressant medications. The most commonly used of these drugs are Prozac, Elavil, and Tofranil. The anti-PSP benefit of these drugs seems to be unrelated to their ability to relieve depression.
A surgical procedure, a gastrostomy, may be necessary when there are swallowing disturbances. This surgery involves the placement of a tube through the skin of the abdomen into the stomach (intestine) for feeding purposes.
Currently, clinical research trials with free radical scavengers (agents that can get rid of potentially harmful free radicals in the brain) are being planned for PSP. Ongoing research focusing on Parkinson and Alzheimer diseases should shed light on the disease process at work in PSP, as well as suggest effective therapies.
Management and Prognosis
As with all FTDs, the pattern of signs and symptoms of PSP can be quite different from person to person.
Management of PSP symptoms can take many forms. Patients frequently use weighted walking aids to counteract their tendency to fall backward. Bifocals or special glasses called prisms are sometimes prescribed for PSP patients to remedy the difficulty of looking down. Although formal physical therapy is of no proven benefit in PSP, exercises can be done to keep the joints limber.
PSP gets progressively worse but is not itself directly life-threatening. It does, however, predispose patients to serious complications such as pneumonia secondary to difficulty in swallowing (dysphagia). The most common complications are: choking and pneumonia, head injury, and fractures caused by falls. The most common cause of death is pneumonia. With good attention to medical and nutritional needs, however, most PSP patients live well into their 70s and beyond.
For additional information and support:
Society for Progressive Supranuclear Palsy
Woodholme Medical Building
1838 Greene Tree Road, #515
Baltimore, MD 21208
spsp@psp.org
http://www.psp.org
Tel: 410-486-3330 800-457-4777
Fax: 410-486-4283
___
Material prepared by Jennifer M. Farmer, MS, CGC, Website Clinical Consultant and Susan L-J Dickinson, MS, CGC, Website Medical and Science Writer.
Votes:29
Comments: 0