Parkinson’s disease: A primer

Here’s what you need to know about Parkinson’s – what it is and how it can be managed.

Approximately 100,000 Canadians suffer from Parkinson’s disease – 1 per cent of the population over 60 and 2 per cent of the population over 70. 20 per cent of those diagnosed are under 50 years of age. What is Parkinson’s and how can it be managed? Here’s a primer.

What is Parkinson’s disease?
Parkinson’s disease is a degenerative disorder of the central nervous system that often impairs the sufferer’s motor skills and speech. It is both chronic and progressive. Its key components include muscle rigidity, tremors, and a slowing of physical movement which can become a loss of movement. Other symptoms can include cognitive impairment and language problems.

Parkinson’s disease is not a ‘new’ disease. It was first formally described in An Essay on the Shaking Palsy, published in 1817 by James Parkinson. It has probably existed for many thousands of years. Its symptoms and potential therapies were also mentioned in the Ayurveda, the system of medicine practiced in India as early as 5000 BC, and in the first Chinese medical text, Nei Jing, which appeared 2500 years ago. Most recently, actor Michael J. Fox, who suffers from the disease, has created a foundation to push for a cure in this century, and brought the public’s attention to the disease.

Despite this long history, the root cause of Parkinson’s is not known. Recent studies suggest it has a genetic component, but may be triggered by the environment. It is known that the symptoms are related to a lack of dopamine production in the brain. Dopamine is a neurotransmitter (chemical in the brain) that is related to adrenaline, and it is linked to movement, emotional response, and capacity to feel pleasure and pain.

Symptoms and diagnosis
Parkinson’s disease usually begins with subtle symptoms, although it progresses at different rates in different people. The tremors or shaking which affect most Parkinson’s patients may interfere with daily activities. Difficulty swallowing, chewing, and speaking may be earlier symptoms. Depression and other emotional changes may take place. Other symptoms include urinary problems, skin problems, and sleep disruptions. Reduced facial expressions and speaking in a soft voice are also indicative of Parkinson’s.

Diagnosing Parkinson’s disease is a process of elimination, as there are no tests that have been shown to pinpoint Parkinson’s disease. It can be difficult to diagnose properly. Generally other diseases are eliminated through tests, and then a medical history and a neurological examination will determine if symptoms point towards Parkinson’s disease.

The prognosis for the disease varies from person to person. Some people experience only minor motor dysfunction; others become severely disabled.

The first approved treatment for Parkinson’s, a drug called levodopa, or l-dopa. This drug becomes dopamine in the brain, and often provides an appreciable lightening of symptoms. However, over time it can become less effective, requiring higher doses. The drug itself also causes tics, involuntary movements, and hallucinations in some patients.