The history of the use of pharmaceuticals to alleviate the symptoms of Parkinson's disease (PD) began 125 years ago, when belladonna alkaloids were first used in an attempt to control severe drooling in patients suffering from PD. These alkaloids possess anticholinergic activity, and unexpectedly, they alleviated other characteristic symptoms of PD, which include tremor, rigidity, akinesia and postural instability. However, it was not until 1958 that researchers discovered the presence of high levels of dopamine in the striatum of the brain and showed that the dopamine precursor (levodopa or L-dopa) reversed the tranquillization and parkinsonian-like motor impairments induced by treatment with reserpine. This set the stage for the development of the first real pharmacotherapy for treatment of PD.

Sanjiv CC, DM,
Tsui JKC, MD, FRCPC
Neurodegenerative Disorders Centre,
University of British Columbia,
Vancouver, BC, Canada

Dopaminergic Agents
At present, there is no pharmacological cure for Parkinson's disease (PD) and only the symptoms of the disease can be treated. There is no firm evidence to support the notion that any drug has a neuroprotective action in PD; therefore, the mainstay of current drug therapy is the manipulation of the dopaminergic pathways.

Levodopa (L-DOPA)
L-dopa is the most commonly prescribed medication for the treatment of PD.

Janis Miyasaki, MD, FRCPC
Mount Sinai Hospital,
Movement Disorders

Each year Parkinson's disease (PD) affects 4.5-21 people out of every 100,000. The prevalence rate is 200/100,000 members of the population. As the population ages, the prevalence can be expected to increase since the risk of developing PD steadily increases with each decade of life.¹ The cardinal symptoms of PD are tremor, rigidity, akinesia and postural instability.² A patient is diagnosed with Parkinson's disease based on him/her having a history consistent with PD, and showing the clinical signs on examination. Therefore, the physician must be familiar with the classic appearance of each sign of PD and with the alternative diagnoses that are implied by any variance in symptoms.

Tremor
The tremor in PD is classically 3-5 Hz and is described as pill-rolling, due to the rhythmic opposition of the index finger and thumb. Tremor is seen at rest, however, in some cases it may only be seen if the patient is distracted by the use of manoeuvres such as mental arithmetic. While the patient is walking, the affected arm will often shake. Anxiety markedly increases the tremor, whereas it abates during sleep. Tremor may also be seen with postural maintenance or during a physical action. If the postural or kinetic component of the tremor is predominant, the physician should consider an enhanced physiologic tremor or essential tremor as the diagnosis.

Basal Ganglia Motor Circuit is Target Site for Surgical Intervention

Farooq I. Khan, MD,
Robert Chen, MBBChir, MSc, FRCPC
Movement Disorders Centre,
Division of Neurology,
Toronto Western Hospital,
University of Toronto

Parkinson's Disease (PD) was first described by James Parkinson in 1817, and is a neurodegenerative disease that is characterized by tremor, bradykinesia, rigidity and postural instability. It results from the degeneration of the dopaminergic neurons in the substantia nigra (pars compacta) causing alterations in the basal ganglia circuitry; this circuitry is responsible for modulating and facilitating motor function through the cerebral cortex. The evolution of the treatment for PD has relied on both pharmacological and surgical approaches, arguably the most important of which was the discovery of levodopa in the early 1960s. Since then a number of other pharmacological agents such as monoamine oxidase (MAO) inhibitors, catechol-O-methyltransferase (COMT) inhibitors, and dopamine agonists, have played a vital role in the amelioration of disability arising from this disease. Unfortunately, long term pharmacotherapy, especially with levodopa, has caused problems of its own, namely the occurrence of fluctuation and dyskinesia. For these and other reasons that will be discussed, surgery has offered a ray of hope to combat this eventually crippling disease.

Eleanor Brownridge

Empowerment is the goal of a two-year-old program for people with Parkinson's. The Parkinson's Early Intervention Program at Baycrest Centre for Geriatric Care in Toronto is a 10-week education and exercise program for newly-diagnosed patients. Spouses are also encouraged to attend the twice weekly, two-hour sessions.

"Our goal is [to] help the participants develop problem-solving and health behaviour changes," says senior physiotherapist, Rebecca Gruber, the coordinator of the program. "We want to give them a sense of control over their destiny by encouraging them to set and achieve personal goals suitable for their lifestyle."

Physiotherapist Jan Goldstein (left) leads stretching exercise with members of the Parkinson's
Early Intervention Program at Baycrest Centre for Geriatric Care.

Patients applying for the program should have been diagnosed with Parkinson's within the last three years. "Time is of the essence," says Gruber. "Early intervention with appropriate exercises can prevent or delay some of the disabilities that commonly occur." To make it easier for the newly-diagnosed Parkinsonian, all the resources and expertise needed have been brought together under one roof.