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FYI to the the Parkinsn's mailing list. I noticed that many of you are asking questions which are answered in the handout I give when I visit PD support groups. Let me know if anyone finds this helpful. Introduction Parkinson's Disease (PD) was first formally described by James Parkinson in 1817. Prior to James Parkinson during the 18th century, the features were noted but the disease was not fully described. In the early 1900's a epidemic of Encephalitis lethargica in Europe left many people with Parkinson's-like malady as a residual illness after surviving flu-like condition. This outbreak greatly increased the number of patients with parkinsonism and was important in that it taught us that all that shakes is not PD. It was than realized that other causes of bradykinesia (slow movements) and tremor exist. The first breakthrough in therapy came with the introduction of Levo-Dopa therapy in the 1960's. Today there are numerous new therapies to treat different aspects of PD and to slow the progression of the disease. Another exciting advance in the understanding of PD came about when it was discovered that a street drug called MPTP caused PD by producing neurotoxins in the brain. This lead to the discovery that drugs that inhibit the formation of neurotoxins are partially protective for PD. Scope of the Problem Parkinson's Disease is not rare. There are over 300,000 sufferers of PD with 40,000 new cases diagnosed per year. The cost is tremendous. This represents hundreds of millions of dollars of lost revenue, not to mention the cost of medications, therapies, and to care givers. Risk Factors PD commonly affects the age group of 40-90 year olds. It affects men slightly more than women, and affects the white race more that the Japanese, Chinese and African races. There may be a slight genetic predisposition (keep in mind that there are many PD look-alikes which are inherited). There has not been a proven association with exposure to rural homes, farming, well water, herbicides or pesticides. Infection of a fetus with the flu may increase the risk of developing PD later in life. Trauma has not been shown to increase the risk of PD, however boxers may develop pugalistic PD after long careers in boxing. Emotional stress is though to be a risk factor. Protective Factors The protective effects of cigarettes, vitamin C, E, beta-carotene, cod liver oil or protein calories or lack of protein has not been proven. Protein in food is known to decrease the absorption of Sinemet by competing with binding sites in the gut. Clinical Features of PD The first symptom that a patient may notice may be tremor, rigidity, akinesia (freezing), postural disturbance or balance problems. Tremor is the most common complaint. There may also be dystonia (abnormal movements), fatigue, depression, anxiety, restlessness, poor handwriting, quieting of voice, change in posture, muscle aches, cramping or paresthesias (tingling feelings). The gait is shuffling with a stooped posture, narrow base and flexed knees with turning en bloc. The severity of PD is divided into 5 stages, and the treatment is tailored to the stage. Parkinsonism Look-Alikes Pathologic studies into the underlying cause of PD have lead to the discovery of a number of other diseases which share clinical features to PD. Approximately 80% of patients who present with the symptoms above will be found to have idiopathic PD. Approximately 8% have secondary PD (due to toxins, drugs, trauma, metabolic disorder, infection stroke, brain tumor). About 10% have Parkinson plus syndromes, a group of disorders with multiple system degeneration with neurologic involvement beyond the typical features of PD. These include eye movement problems in Progressive Supranuclear Palsy (PSP), dysautonomia (problems with blood pressure, digestion, etc...) in Shy Drager Syndrome (SDS), ataxia (poor coordination) in OlivoPontoCerebellar Atrophy (OPCA), apraxia (poor fine motor control), myoclonus (jerking) and alien hand in CorticoBasal Ganglionic Degeneration (CBGD), dementia in Alzheimer's Disease with Parkinsonism (ADP) or diffuse Lewy Body Disease (LBD), dementia with motor neuron disease with Parkinsonism Dementia Amyotrophic Lateral Sclerosis (PD-ALS). These diseases usually have less tremor, early problems with gait and poor response to Sinemet. Progressive Surpanuclear Palsy This disorder accounts for 7% of parkinsonism and merits special mention here. The gait is stiff, extended, broad based with pivoting instead of turning en bloc. The earliest problems are with balance and have had falls. There is dysarthia (slurred speech) dysphagia (swalling problems) and emotional incontinence. There is paralysis of downward gaze. The response to medications is less than in PD. The other PD look-alikes will not be discussed further due to time constraints. Treatment with Sinemet Most of the audience is familiar with Levo-Dopa/Carbidopa therapy. L-Dopa is converted to Dopamine in the brain in cells in the substantia nigra. Carbidopa prevents some of the side effects of conversion outside the brain. Sinemet requires intact cells in the brain and places some stress on these cells. For this reason, Sinemet is sometimes withheld until the later stages of the disease, and has a limited length of time for its use. Other medications may be tried with and without Sinemet to protect the cells and to lessen the requirement for Sinemet. Problems with On/Off effects and dystonia have been lessened by the use of continuous release Sinemet (CR). Treatment with Selegiline (Deprenyl, Edepryl) Selegiline increases the length of action and the magnitude of the effects of Sinemet. It is thought that it also slows the progression of PD by inhibiting the production of toxins in the brain which destroy brain cells. Treatment with Dopamine Agonists Drugs that act directly on receptors rather than requiring the conversion to dopamine by intact brain cells were developed to address some limitations of Sinemet. These drugs are believed not to put as much strain on brain cells and allow the dosage of Sinemet to be lessened. Examples of these drugs are bromocriptine (Parlodel), pergolide (Permax), Lisuride (available in Europe only) and apomorphine. Treatment with Anticholinergic Medications Drugs that block transmission of are useful in the treatment of PD. These medications also alleviate depression and reduce tremor. Examples include (Symmetrel), benztropine (Cogentin), amitryptiline (Elavil), bedadryl and trihexiphenidyl (Artane). Other Treatments All patients with PD receive extensive evaluation in my clinic. Patients are helped with problems with sleep, depression and daily activities and there is extensive help for care givers as well. Recently medicare has approved the reimbursement for at home nurses and therapists for PD. PD patients often require canes, walkers, dietary changes, modifications of their home and work environments and assistance in their daily activities. PD Surgery Our staff is experienced with state of the art surgery for PD. This consists of neurosurgical transplantation of fetal cells into the the brain to produce dopamine. This treatment is indicated for a small, select group of patients. Reference: Neurologic Clinics "Parkinson's Disease" May 1992, Editors JM Cedarbaum, ST Gancher, Publisher WB Saunders, Harcourt Brace. Page 341. Steve52N.aol.com (Steve Norris)