About Parkinson's Disease

Parkinson’s disease is a chronic, progressive neurological disease. It belongs to a group of conditions called motor system disorders, which are the result of the loss of dopamine-producing brain cells. Dopamine, a neurochemical that controls communication between brain cells, is responsible for control of motor function. Nearly 80 percent of the dopamine producing cells in the brain die before the motor symptoms of Parkinson’s disease even appear. The four primary symptoms of Parkinson’s disease are tremor, or trembling in hands, arms, legs, jaw, and face; rigidity, or stiffness of the limbs and trunk; bradykinesia, or slowness of movement; and postural instability, or impaired balance and coordination. Other symptoms may include cognitive changes; difficulty in swallowing, chewing, and speaking; urinary problems or constipation; skin problems; and sleep disruptions. As these symptoms become more pronounced, patients may have difficulty walking, talking, or completing other simple tasks. Early symptoms of Parkinson’s are subtle and occur gradually. In some people the disease progresses more quickly than in others.

Currently there is no cure, therapy, or drug to slow or halt the progression of Parkinson’s disease. While medication masks some symptoms for a limited period, generally four to eight years, dose-limiting side-effects do occur after time. Eventually the medications lose their effectiveness, leaving the person unable to move, speak or swallow.

In 1817, a British scientist named James Parkinson first described “the shaking palsy” in an essay. It was through this essay that he defined what we know as Parkinson’s disease today: “involuntary tremulous motion, with lessened muscular power, in parts not in action and even when supported; with a propensity to bend the trunk forwards, and to pass from a walking to a running pace: the senses and intellects being uninjured.”

It is unknown exactly how many Americans live with Parkinson’s disease, but most estimates range from 500,000 to 1.5 million. It is believed that nearly 60,000 people are diagnosed each year in the U.S. with Parkinson’s. The average age of diagnosis for Parkinson’s disease is 60 years old, but people as young as 18 have been diagnosed. Typically, anyone diagnosed under the age of 50 is considered as having young-onset Parkinson’s disease.

The cause of Parkinson’s disease remains unknown, but scientists and researchers believe there to be both genetic and environmental factors. In October 2003, scientists at NIH discovered that too much of the alpha-synuclein gene may cause Parkinson’s disease. More recently, scientists at the University of California at Los Angeles discovered that some pesticides used on plants and crops that end up in well water are linked to an increased risk of Parkinson’s disease. The environmental and genetic links to Parkinson’s disease are diverse, but the science continues to progress.

In order to establish better numbers and understanding about people with Parkinson’s, Congress has taken up a bill, H.R. 2595/S. 425, the National Neurological Diseases Surveillance System Act, that will create national, coordinated registries for both Parkinson’s disease and all neurological disorders. When the registry is implemented, we will learn important information about Parkinson’s disease such as geographic prevalence, disease clusters, and the number of Americans living with Parkinson’s disease.

PAN continues to fight for better treatments and a cure for Parkinson’s disease. Click here to learn more about PAN’s legislative priorities for the Parkinson’s disease community.