As people around the world continue to mourn the tragic loss of Robin Williams, his wife Susan Schneider recently revealed the beloved actor was in the early stages of Parkinson's Disease prior to his death.
Parkinson's Disease (PD) is a progressive condition that happens when the brain's nerve cells don't produce enough dopamine, a chemical that sends signals to an area of the brain that controls movement and coordination. This neurological disorder is somewhat common in the United States: The Parkinson's Disease Foundation reports that nearly 1 million Americans live with the condition and 50,000 to 60,000 new cases of PD are diagnosed each year.
Here are five more things to know about Parkinson's Disease.
Tremors aren't the only symptom
You might know already that Parkinson's is marked by tremors of the hands, arms, and legs, but there are some other common symptoms. People with this disease might also experience stiffness of the limbs, slowness of movement, and poor balance and coordination, according to The National Institute of Neurological Disorders and Stroke. Symptoms may first appear on one side of the body and later they will affect both sides.
As the disease progresses, people with PD may start having difficulty walking and the tremors may intensify. Many people with Parkinson's can experience non-motor symptoms as well, including bladder problems, constipation, difficulty speaking or swallowing, and depression, which Williams also struggled with in the past. While some people experience only minor motor disruptions, others can become severely disabled.
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It can affect younger people
While the National Parkinson's Foundation says that the average age of diagnosis is 62, some people develop the disease much sooner than that. One of the most well-known people with Parkinson's is Michael J. Fox, now 53, who was diagnosed near his 30th birthday in 1991. When the disorder is diagnosed before the age of 50, it's called Young-Onset Parkinson's. In people diagnosed at a young age, the disease may progress slower, but involuntary muscle spasms are more frequent, leading to abnormal movement and posture. In rare cases, teenagers and children can have Parkinson’s-like symptoms, but it's considered a distinct disease.
It's difficult to diagnose
There's actually no standard diagnostic test for the disorder, according to the Parkinson's Disease Foundation. So most physicians have to rely on a neurological exam and the medical history provided by the patient to diagnose the condition. Your doctor might look for things like uneven arm swing, tremors that persist in your arms when they're rested or extended, as well as difficulties with balance and stiffness in the limbs or neck.
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Risk factors aren't clear-cut
In general, the disease tends to hit men more than women, and people over 60. Not much is known about what causes Parkinson's, but it's thought to be sparked by a combination of genetic and environmental factors. There are two types of genes that researchers focus on when it comes to Parkinson's: People with the causal genes will get Parkinson's regardless of other factors, while mutations in associated genes only increase the risk of developing PD, the Parkinson's Disease Foundation reports. And most cases of PD are not inherited: Only 15 to 25% of people with Parkinson’s report having a relative with the disease. In the case of associated genes, environmental factors might play a role. Exposure to pesticides and prior head injury are just a few of the possible culprits studied by researchers, but clear links haven't been established.
No cure exists, but PD can be managed
There is no cure for Parkinson's Disease. A few different medications exist to treat the symptoms of Parkinson's, but one combo drug helps nearly 75% of cases: Levodopa. It's combined with another drug, Carbidopa, and works to help nerve cells make much-needed dopamine, according to the National Institute of Neurological Disorders and Stroke. Levodopa can help ease rigidity and slowness of movement, but can have some side effects after prolonged use like spontaneous and involuntary movements, known as dyskinesias. But most doctors encourage people to start treatment early to reduce risk of falling.