Conquering Another Challenge: Progressive Supranuclear Palsy
Just a decade ago my Grandmother was able to hike her favorite destinations with ease and as long as I can remember I was being shown pictures of every place she had climbed, hiked, or visited. She would share her stories with me over a home cooked meal, or during a nice afternoon hike in the Arizona desert. A woman who is as strong, active, and in good health as she is should be enjoying her senior years; unfortunately she can not because she is gradually deteriorating from a brain disease called PSP.
What is Proressive Supranuclear Palsy?
This is a rare brain disorder that causes serious and "progressive" issues with control of gait and balance, along with complex eye movement and thinking problems. Individuals who are affected often experience alterations in mood and behavior, i.e. depression, apathy, and progressive mild dementia. This disease begins slowly and continues to get worse and cause weakness by damaging certain parts of the brain. PSP was first described as a "distinct disorder" in 1964; affected people DO NOT die from PSP itself.
Who gets PSP and what are the symptoms?
Approximately 1 in every 100,000 people over the age of 60 have PSP, making it much less common than Parkinson's disease, which affects more than 500,000 Americans. Affected individuals are usually middle-aged or elderly, and men are affected more often than women. PSP is often difficult to diagnose because its symptoms can be very much like those of other, more common movement disorders, and because some of the most characteristic symptoms may develop late or not at all. The most frequent first symptom of PSP is a loss of balance while walking. Individuals may have unexplained falls or a stiffness and awkwardness in gait. Sometimes the falls are described by the person experiencing them as attacks of dizziness. Other common early symptoms are changes in personality such as a loss of interest in ordinary pleasurable activities or increased irritability, cantankerousness, and forgetfulness. Individuals may suddenly laugh or cry for no apparent reason, they may be apathetic, or they may have occasional angry outbursts, also for no apparent reason. It must be emphasized that the pattern of signs and symptoms can be quite different from person to person. As the disease progresses, most people will begin to develop a blurring of vision and problems controlling eye movement. In fact, eye problems usually offer the first definitive clue that PSP is the proper diagnosis. Individuals affected by PSP have trouble voluntarily shifting their gaze downward, and also can have trouble controlling their eyelids. This can lead to involuntary closing of the eyes, prolonged or infrequent blinking, or difficulty in opening the eyes. Another common visual problem is an inability to maintain eye contact during a conversation. This can give the mistaken impression that the person is hostile or uninterested. Speech usually becomes slurred and swallowing solid foods or liquids can be difficult.In rare cases, the symptoms will be more similar to those of Parkinson disease, and some individuals may even have tremors. This version is often referred to as “Parkinsonian PSP” or PSP-P.
What Causes PSP?
Scientists do not fully know what causes these brain cells to degenerate, but it is known that a hallmark of the disease is the accumulation of an abnormal protein called tau. There is no evidence that PSP is contagious, and genetic factors have not been implicated in most individuals. No ethnic or racial groups have been affected more often than any others, and PSP is no more likely to occur in some geographic areas than in others. There are, however, several theories about PSP's cause. One possibility is that an unconventional virus-like agent infects the body and takes years or decades to start producing visible effects. Another possibility is that random genetic mutations, of the kind that occur in all of us all the time, happen to occur in particular cells or certain genes, in just the right combination to injure these cells. A third possibility is that there is exposure to some unknown chemical in the food, air, or water which slowly damages certain vulnerable areas of the brain. Another possible cause of PSP is cellular damage caused by free radicals, reactive molecules produced continuously by all cells during normal metabolism. Although the body has built-in mechanisms for clearing free radicals from the system, scientists suspect that, under certain circumstances, free radicals can react with and damage other molecules. A great deal of research is directed at understanding the role of free radical damage in human diseases.