Friday, July 6, 2007

Misconceptions of Parkinson's Disease

Misconceptions regarding Parkinson’s Disease

Dr NK Chew, Consultant Neurologist
Kuala Lumpur.
5th July 2007.

During one of my Outpatient Clinic sessions, a 65 years old gentleman was diagnosed for the first time to have Parkinson’s Disease. He presented with difficulty walking and slowness of movement for about six months. She was brought to the hospital by her daughter. Upon hearing the diagnosis, her daughter was obviously distressed and sad. After prescribing the medication, the patient left my clinic but her daughter stayed to ask me this question – doctor, how many months longer can my father live?

I gave her a lengthy explanation about the illness and reassured her that she had misunderstood the illness. Before she left the clinic, she thanked me for giving her a big relief. She must have thought her beloved father would live for only another few months after the diagnosis was made.

This was a good example to illustrate the importance of having a clear understanding of this illness. Patients and caregivers often have many questions and misconception regarding Parkinson’s Disease. Unfortunately, doctors are often too busy to give adequate explanation about the illness in the clinic. Thus, the objective of this article is to clarify various misunderstanding about the illness that usually cause unnecessary anxiety among newly diagnosed patients and caregivers. The following is some of the common misconceptions that I have encountered in my clinical practice.

a) When you have Parkinson’s Disease, you only have several months to live

The drug (levodopa) for treating Parkinson’s Disease was discovered only in the 1960’s. Before the 1960’s, one study showed that untreated patients lived for an average of 10 years after diagnosis. As the physical disability in Parkinson’s Disease worsened with time, eventually patients became bed-ridden and succumbed to lung infection. This contributed to the shorter life span of Parkinson patients compared with those without Parkinson’s Disease.

Following the introduction of levodopa, the chances of survival of treated patients had significantly increased. With the use of levodopa, another study showed that patients’ quality of life had significantly improved and they could live for an average of 15 years. Nowadays, there are less patients who succumb to Parkinson’s Disease and more patients succumb to other common illnesses of old age such as stroke and heart attack.

In 1999, I carried out a study on 153 patients seen at University Hospital, Kuala Lumpur and found that the patients had had the illness for an average duration of 7.3


years, ranging from 6 months up to 21 years. Therefore, Parkinson’s Disease is certainly not a case of terminal stage of cancer whereby patients have only a few months left to live.

b) Parkinson’s Disease is caused by stroke

As Parkinson’s Disease and stroke usually occur in the elderly people, naturally some people think Parkinson’s Disease is caused by stroke. Actually both this illnesses are totally unrelated to each other. Stroke is characterized by sudden weakness of body caused by blockage of blood vessels and reduced amount of blood going to the brain. In contrast, Parkinson’s Disease is due to a progressive loss of certain cells in the brain that lead to slowness of movement. The symptoms Parkinson’s Disease begin very slowly unlike in stroke, and sometimes patients themselves may not remember exactly when the symptoms had started.

c) Parkinson’s Disease leads to dementia soon after diagnosis

Parkinson’s Disease is often confused with Alzheimer’s disease, a condition which is characterized by dementia (memory loss and change in behaviour). One of the reasons for the confusion is that both illnesses typically occur in the elderly people.

The difference between Parkinson’s Disease and Alzheimer’s Disease is that during the first ten years of illness, Parkinson’s patients usually have normal memory. In contrast, Alzheimer’s patients have poor memory right from the onset of illness. However, this rule is applicable only during the first ten years of illness.

Studies have shown that about 20% of Parkinson’s patients subsequently developed dementia, which occurred after a period of about ten years. Thus, a small percentage of Parkinson’s patients do develop memory problem during the late stage of illness.

d) Patients with Parkinson’s Disease will be paralysed and bed-ridden very soon after diagnosis

As mentioned earlier, the physical disability of Parkinson’s Disease does worsen as time goes by. Until today, there is still no cure for this illness. In the past, many patients eventually became bed-ridden. However, with the advent of more effective treatment (drugs and surgery) for Parkinson’s Disease, the scenario has changed for the better. There are more and more patients who remain reasonably active for many years (up to 15 years after having illness). Indeed, it is rare to see any Parkinson’s patient who is bedridden nowadays. I know some patients who continue playing tennis and badminton regularly despite having the illness for five years.

e) Parkinson’s Disease is caused by unhealthy food

Some studies have shown that Parkinson’s Disease has been associated with inadequate intake of vitamin E. In our study on Parkinson’s Disease in University Hospital, we found that there were disproportionately higher number of Malaysian Chinese patients than other races. We postulated that it could be due to the dietary habit of Malaysian Chinese


who preferred raw or half-cooked vegetables that may contain pesticides (chemicals that may cause changes in the brain leading to Parkinson’s Disease). Interestingly, people who regularly drink coffee have been reported to have lower chance of developing Parkinson’s Disease.

However, it has to be emphasized that all these are merely observations and the role of food in causing Parkinson’s Disease is still not proven.

f) The children of Parkinson’s patients have a strong possibility of inheriting the illness

The causation of Parkinson’s Disease has been attributed to the interplay between genetic and environmental factors. In other countries, 6-24% of cases have family members affected by the same illness. However, in our study in University Hospital, only 2% of Parkinson patients have affected family members. Thus, the possibility of children of Parkinson patients in Malaysia inheriting the same illness is very small and should not be
a major cause of concern.

g) Parkinson’s Disease can be transmitted to family members by an infection

This is a cause of concern among the immediate family members of Parkinson patients. Virus infection of the brain can rarely cause other types of brain disease with symptoms that resemble Parkinson’s Disease. However, this is very rare. Parkinson’s Disease itself has not been proven to be caused by infection of the brain. Thus, family members do not have to worry about acquiring the similar illness via infection.

In conclusion, adequate understanding of this illness is vital to avoid unnecessary anxiety. I hope that this article has helped to eliminate the misconceptions regarding Parkinson’s Disease.

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