Parkinson's Disease is named after a British physician, James Parkinson, who first described it in “An Essay on the Shaking Palsy” in 1817. The National Institute on Aging has put together a nice summary of Parkinson's Disease [referenced, infra].
It is important to know that while Parkinson's usually affects older individuals that are already beyond the age of retirement (>65 years), it can sometimes affect younger individuals that are still working and who require long-term disability benefits. [See: “Michael J. Fox,” infra.].
Symptoms from Parkinson's include tremor, shaking, stiffness, and difficulty with walking (shuffling gait), balance, and coordination. As the disease progresses, people may have difficulty walking and talking. They may also have mental and behavioral changes, sleep problems, depression, memory difficulties, cognitive impairment, and fatigue.
What Causes Parkinson's Disease?
Parkinson's disease occurs when nerve cells (neurons) in an area of the brain that controls movement called the basal ganglia and the substantia nigra become impaired and/or die. Normally, these neurons produce a neurotransmitter chemical called dopamine. When the neurons die or become impaired, they produce less dopamine, which causes the movement problems of Parkinson's. Scientists still do not know what causes cells that produce dopamine to die.
People with Parkinson's also lose the nerve endings that produce norepinephrine, the main chemical messenger of the sympathetic nervous system, which controls many automatic functions of the body, such as heart rate and blood pressure. The loss of norepinephrine might help explain some of the non-movement features of Parkinson's, such as fatigue, irregular blood pressure, decreased movement of food through the digestive tract, and sudden drop in blood pressure (orthostatic hypotension) when a person stands up from a sitting or lying-down position.
Many brain cells of people with Parkinson's contain Lewy bodies, unusual clumps of the protein alpha-synuclein. Scientists are trying to better understand the normal and abnormal functions of alpha-synuclein and its relationship to genetic mutations that impact Parkinson's disease and Lewy body dementia.
Although some cases of Parkinson's appear to be hereditary, and a few can be traced to specific genetic mutations, in most cases the disease occurs randomly and does not seem to run in families. Many researchers now believe that Parkinson's disease results from a combination of genetic factors and environmental factors such as exposure to toxins.
Symptoms of Parkinson's Disease
Parkinson's disease has four main symptoms:
- Tremor (trembling) in hands, arms, legs, jaw, or head
- Stiffness of the limbs and trunk
- Slowness of movement
- Impaired balance and coordination, sometimes leading to falls
Other symptoms may include depression and other emotional changes; difficulty swallowing, chewing, and speaking; urinary problems or constipation; skin problems; and sleep disruptions.
Symptoms of Parkinson's and the rate of progression differ among individuals. Sometimes people dismiss early symptoms of Parkinson's as the effects of normal aging. In most cases, there are no medical tests to definitively detect the disease, so it can be difficult to diagnose accurately.
Early symptoms of Parkinson's disease are subtle and occur gradually. For example, affected people may feel mild tremors or have difficulty getting out of a chair. They may notice that they speak too softly, or that their handwriting is slow and looks cramped or small. Friends or family members may be the first to notice changes in someone with early Parkinson's. They may see that the person's face lacks expression and animation, or that the person does not move an arm or leg normally.
People with Parkinson's often develop a parkinsonian gait that includes a tendency to lean forward, small quick steps as if hurrying forward, and reduced swinging of the arms. They also may have trouble initiating or continuing movement.
Symptoms often begin on one side of the body or even in one limb on one side of the body. As the disease progresses, it eventually affects both sides. However, the symptoms may still be more severe on one side than on the other.
Many people with Parkinson's note that prior to experiencing stiffness and tremor, they had sleep problems, constipation, decreased ability to smell, and restless legs.
Diagnosis of Parkinson's Disease
Several disorders can cause symptoms like those of Parkinson's disease. People with Parkinson's-like symptoms that result from other causes are sometimes said to have parkinsonism. While these disorders initially may be misdiagnosed as Parkinson's, certain medical tests, as well as response to drug treatment, may help to distinguish them from Parkinson's. Since many other diseases have similar features but require different treatments, it is important to make an exact diagnosis as soon as possible.
There are currently no blood or laboratory tests to diagnose nongenetic cases of Parkinson's disease. Diagnosis is based on a person's medical history and a neurological examination. Improvement after initiating medication is another important hallmark of Parkinson's disease.
Treatment of Parkinson's Disease
Although there is no cure for Parkinson's disease, medicines, surgical treatment, and other therapies can often relieve some symptoms.
Medicines prescribed for Parkinson's include:
- Drugs that increase the level of dopamine in the brain
- Drugs that affect other brain chemicals in the body
- Drugs that help control nonmotor symptoms
The main therapy for Parkinson's is levodopa, also called L-dopa. Nerve cells use levodopa to make dopamine to replenish the brain's dwindling supply. Usually, people take levodopa along with another medication called carbidopa. Carbidopa prevents or reduces some of the side effects of levodopa therapy—such as nausea, vomiting, low blood pressure, and restlessness—and reduces the amount of levodopa needed to improve symptoms.
People with Parkinson's should never stop taking levodopa without telling their doctor. Suddenly stopping the drug may have serious side effects, such as being unable to move or having difficulty breathing.
Other medicines used to treat Parkinson's symptoms include:
- Dopamine agonists to mimic the role of dopamine in the brain
- MAO-B inhibitors to slow down an enzyme that breaks down dopamine in the brain
- COMT inhibitors to help break down dopamine
- Amantadine, an old antiviral drug, to reduce involuntary movements
- Anticholinergic drugs to reduce tremors and muscle rigidity
Deep Brain Stimulation
For people with Parkinson's who do not respond well to medications, deep brain stimulation, or DBS, may be appropriate. DBS is a surgical procedure that surgically implants electrodes into part of the brain and connects them to a small electrical device implanted in the chest. The device and electrodes painlessly stimulate the brain in a way that helps stop many of the movement-related symptoms of Parkinson's, such as tremor, slowness of movement, and rigidity.
Other therapies may be used to help with Parkinson's disease symptoms. They include physical, occupational, and speech therapies, which help with gait and voice disorders, tremors and rigidity, and decline in mental functions. Other supportive therapies include a healthy diet and exercises to strengthen muscles and improve balance.
Genetics of Parkinson's Disease
Probably 90% of patients who develop Parkinson's Disease have no evidence of genetic abnormalities. However, some patients with Parkinson's have mutations in a gene called SNCA (alpha-synuclein), while other patients have mutations in the gene LRRK2. This is particularly true in Ashkenazi (Eastern European) Jews.
For the most part, there is no known cause of Parkinson's and genetics do not appear to be a significant factor.
Parkinson's Disease in the Media
The 1990 movie “Awakenings,” based on a story by Oliver Sacks and starring Robert De Niro and Robin Williams, depicted how L-dopa was first used to successfully treat severely affected patients with Parkinson's who were essentially catatonic from their disease.
Michael J. Fox and Parkinson's Disease
The actor, Michael J. Fox, was diagnosed with Parkinson's disease at 29 years of age. He was shooting the motion picture “Doc Holiday” when his symptoms started. He retired from show business in 2000, as his symptoms worsened. He started a foundation, the Michael J. Fox Foundation, to support awareness, education, and research in Parkinson's Disease.
Medical Marijuana and Parkinson's Disease
The Michael J. Flox Foundation has reported that some patients received benefit from medical marijuana, according to Dr. Laszlo Mechtler, from Dent Neurologic Institute in New York. He reported that nearly 70% of people, had some improvement in pain, sleep, neuropathy, and anxiety, but about 34% of patients developed sleepiness, balance problems, and upset stomach. [Reference: FoxFeed Blog, March 5, 2019.]
Stem Cell Research in Parkinson's Disease
There are several different kinds of “stem cells” that are being used in treatment and research.
- Embryonic stem cells come from a human embryo created from an in vitro fertilization that is not going to be used.
- Adult stem cells are typically harvested from the blood or bone marrow and are often used to treat blood cancers.
- Umbilical cord stem cells come from the umbilical cord after delivery.
- Mesenchymal stem cells come from tissues that include bone, cartilage, and fat. They are the types of stem cells typically used to treat patients at “stem cell clinics.”
- Induced pluripotent stem cells can be created from adult skin cells or from blood cells that have been reprogrammed to revert to an embryonic state.
- Human parthenogenetic stem cells are derived from an unfertilized human ovum.
The goal of stem cell therapy is to “turn on” stem cells so they turn into dopaminergic neurons (which are the nerve cells that are depleted in Parkinson's disease) and then safely inject them into the brain of a Parkinson's patient. Unfortunately, doctors and scientists have not been able to accomplish this goal so far.[Reference: https://www.apdaparkinson.org/article/understanding-stem-cell-therapy-in-parkinsons-disease-treatment/]
Does stem cell treatment work for Parkinson's? Unfortunately, not yet. Research is continuing, of course, and hopefully it will lead to successful use of stem cells in the future.
Getting Disability Benefits with Parkinson's Disease
Essential Medical Documentation
SSA utilizes the term "Impairments" (and resulting "limitations" - why you cannot work) are the essential bits of information that must be clearly and consistently documented throughout your medical history by the treating sources (medical doctors, neurologists, psychologists, psychiatrists).
SSA additionally utilizes the term "Residual Functional Capacity" (RFC); this is a key concept related to the resulting physical and/or mental impairments from conditions for which the disability claim is based upon and the impact upon ability to work.
SSA has its own forms that are used for Physical RFC here and for Mental RFC here. These forms can be filled out by the treating source who has the opportunity to examine the patient and understand the limitations which result from his/her condition and thereby document with specificity in the language of SSA disability.
SSA has its own forms that are used for Physical RFC here. These forms can be filled out by the treating source who has the opportunity to examine the patient and understand the limitations which result from his/her condition and thereby document with specificity in the language of SSA disability.
SSA "Listing" or "Blue Book" description of Parkinson's for disability benefits can be found here. (see 11.06)