An Overview of Parkinson's Disease

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Parkinson's disease is a progressive disorder that develops as a result of the death of dopamine-producing nerve cells in the brain. Dopamine is a vital chemical messenger that helps regulate muscle activity. When dopamine is depleted, classic Parkinson's symptoms like shaking, stiffness, and walking difficulties can occur.

While Parkinson's disease used to be considered solely a motor disorder, experts now recognize that it also causes non-motor related symptoms like sleeping problems and constipation. What's interesting is that these symptoms may actually predate the motor symptoms by many years, even decades.

Symptoms

The symptoms of Parkinson's disease can be subtle early on. In fact, they may even go unnoticed. But eventually, the symptoms slowly worsen with time.

Hallmark symptoms of Parkinson's include:

  • Tremors: In Parkinson's, this is often called a "pill-rolling tremor" because of the way it appears—as if a person is rolling a pill or other tiny object between his or her thumb and index finger. It's also described as a resting tremor because it occurs when a body part (like, but not limited to, the hand) is relaxed and resting.
  • Bradykinesia: This is a person's decreased ability to move. A person may progress from difficulty using his or her fingers (for example, opening a jar or typing) to difficulty using their legs, leading to a shuffling gait with short steps.
  • Rigidity: A person with rigidity experiences muscle stiffness and resistance to muscle relaxation. They may not swing their arms much when walking, for example. Rigidity can be painful and contribute to difficulty moving.
  • Postural instability: This symptom, defined as a sense of imbalance when standing up, usually arises later on in the course of Parkinson's disease.

Other motor-related symptoms can include decreased eye blinking, speech and swallowing issues, and reduced facial expressions.

Non-motor symptoms of Parkinson's, which are getting increased research attention, include hallucinations, mood disorders, sleep problems, skin issues, and sensory disturbances. Non-motor symptoms are often more debilitating than motor symptoms and can often start years earlier.

Not everyone experiences these additional motor and non-motor symptoms of Parkinson's to the same degree, if at all.

Causes

While the precise cause of a person's Parkinson's disease is as of yet unknown, experts believe that it results from a complex interaction between a person's genes and the environment. Examples of environmental triggers include pesticides and other toxins (although their role is the development of the disease is considered small).

Other risk factors for Parkinson's disease include older age (generally 60 and over) and sex. Men are more likely to have Parkinson's disease than women.

Researchers have also found that changes occur in the brains of people with Parkinson's disease, although it is not clear why. These include clumps of abnormal cells called Lewy's bodies and naturally-occurring proteins called alpha-synuclein that also begin to clump in people with Parkinson's.

By understanding why these occur, scientists may one day unlock the underlying cause of Parkinson's disease.

Diagnosis

The diagnosis of Parkinson's disease requires a careful and thorough evaluation by a doctor, usually a neurologist. They will ask several questions about sleep, mood, memory, walking problems, and recent falls. They will also perform a physical examination to check reflexes, muscle strength, and balance.

There are specific criteria doctors follow to diagnose Parkinson's disease. For example, one that supports a diagnosis is a person with Parkinson-like symptoms demonstrating marked improvement after taking levodopa (a medication commonly used in the treatment of Parkinson's).

While the diagnosis is straightforward in some people, it may be more challenging in others, especially since there are other neurological health conditions that share similar symptoms with Parkinson's disease.

There is no blood test or brain imaging test that can definitively diagnose Parkinson's, but testing may be done to rule out other causes of your symptoms.

Treatment

There is no cure for Parkinson's disease, but there are a number of treatments that can ease its symptoms. Deciding when to start pharmaceutical treatment depends largely on how severe or debilitating those symptoms are. Related side effects of these drugs must also be considered.

Among the commonly prescribed medications and therapies:

  • Carbidopa-levodopa is the primary treatment for Parkinson's disease. Levodopa is converted into dopamine in the body, while carbidopa increases levodopa's penetration into the brain.
  • Dopamine agonists like Mirapex (pramipexole) and Requip (ropinirole) stimulate dopamine receptors and "trick" the brain into thinking it has more dopamine than it has. Dopamine agonists are less effective than levodopa and are often staged for use in early disease before more serious symptoms develop.
  • Monoamine oxidase-B (MAO-B) inhibitors like Zelapar (selegiline) and Azilect (rasagiline) inhibit the enzymes that inactivate dopamine in the brain. Like dopamine, MAO-B drugs are often used in early disease, reserving levodopa for later use.
  • COMT inhibitors like Comtan (entacapone) and Tasmar (tolcapone) work by bolstering the effects of levodopa in the brain. They are used for people in whom levodopa effects are starting to wane.
  • Symmetrel (amantadine) is an antiviral drug used in early Parkinson's disease to manage mild tremors and rigidity.
  • Anticholinergics like Artane (trihexyphenidyl) and Cogentin (benztropine) are prescribed to minimize tremors and spasms. While useful, they are used with caution give possible side effects (e.g., confusion, cognitive decline).
  • Deep brain stimulation (DBS) involves the placement of electrodes and the delivery of electrical impulses to the brain to treat dyskinesia, tremors, and other symptoms when medications are no longer effective.

In the early stages of Parkinson's disease, medications may not be necessary. By delaying treatment until needed, you can preserve your long-term treatment options.

Non-Motor Symptoms

Non-motor symptoms of Parkinson's—such as sleep disorders, cognitive dysfunction, and mood changes—are treated individually. Since many of these symptoms are caused or exacerbated by the drugs used to treat Parkinson's disease, a simple dose adjustment may be all that is needed.

Among the other symptomatic treatment approaches:

  • Antidepressants like selective serotonin reuptake inhibitors (SSRIs) may benefit those with depression, a common disorder in people with Parkinson's.
  • Mild over-the-counter corticosteroid creams can help improve skin problems caused by the long-term use of certain drugs.
  • Antipsychotic drugs like Clozaril (clozapine) and Nuplazid (pimavanserin) may benefit people with visual hallucinations if a dose adjustment fails to provide relief.
  • Rehabilitation therapies like speech, occupational, and physical therapy are commonly used to improve the quality of life in people with Parkinson's disease.
  • Exelon (rivastigmine), a cognitive-enhancing drug typically prescribed as a skin patch, may help people with Parkinson's-associated dementia.

In addition to medical interventions, positive lifestyle choices can enhance your ongoing treatment. This includes routine exercise (to maintain balance and mobility), good nutrition (to ensure energy and manage side effects), good sleep hygiene (to overcome insomnia), and stress reduction (to improve moods and feel better about yourself).

Caregiving

As a caregiver to a loved one with Parkinson's disease, it is not uncommon to feel powerless, overwhelmed, and frightened by the progressive nature of the disease. Fortunately, with the right preparation and resources, you and your loved one will not only learn to cope but thrive in the face of life's challenges.

Here are some key tips to guide you on your caregiving journey:

  • Educate yourself. By becoming knowledgable about all aspects of the disease, you will be better prepared when complications arise. This includes learning about the proper use of medications; knowing the signs and symptoms of disease progression, and educating yourself about beneficial lifestyle choices (including diet and exercise).
  • Be adaptable. While it is important to keep a strict routine with things like medications, you should also remember that Parkinson's is a disease marked by uncertainty. Try not to be stressed if everyday tasks take longer or plans go awry because of a sudden change in your loved one's mood or mobility. By keeping a sense of humor and simply "rolling with it," you'll feel less like a victim of circumstance.
  • Anticipate symptoms. As your loved one's primary caregiver, you are in the best position to note sudden or subtle changes in behavior, symptoms, abilities, or moods. By reporting these to your healthcare provider, treatments can be adjusted or safeguards taken to protect your loved one from harm.
  • Seek supportive aids. As your loved one's physical abilities begin to change, it is best to introduce mobility aids (like walkers and lifts) and room modifications (like handrails and walk-in tubs) before the limitations become profound. It allows your loved one to adapt to these changes gradually while reducing the stress placed on you physically.
  • Find support. As a long-term caregiver, it is important to reach out to others for the support you need to remain healthy emotionally. This includes friends, family, and support groups who can provide you a safe space to express yourself openly and honestly.

If you are unable to cope, do not hesitate to ask your doctor for a referral to a psychologist or psychiatrist who can offer ongoing counseling or medications if needed.

A Word From Verywell

Parkinson's disease is a complex disorder that affects not only how a person moves but also how they feel, sleep, behave, and think. As challenging as this may be, with education and patience, you can begin the process of normalizing the disease in your life and maintaining an optimal quality of life.

It is important to remember that Parkinson's disease, like other degenerative conditions, affects the entire family. By working together and caring for each other's needs, you can become masters of the disease rather than letting the disease master you.

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