Parkinson’s disease (PD) is a slowly progressing neurodegenerative disorder that affects movement. It can cause tremors in many people but not all cases. Slowing of movement and muscle stiffness are also common. About 60,000 people in the U.S. are diagnosed with PD each year with the frequency being 1.5 greater in men than it is in women.
PD tends to occur with advanced age (60 and over) with only 4% of people diagnosed before 50 years of age. According to the Parkinson’s Foundation, the economic burden of PD totals nearly $52 billion yearly. PD medications alone can cost up to $2,500 each year and surgery costs an estimated $100 billion annually.
Signs and symptoms
- Resting tremors are those that occur when a person is not moving. These tremors may first occur in the hands and fingers before developing into a “pill rolling” tremor, which causes someone to rub their thumb and finger back and forth repetitively.
- Bradykinesia or slowed movement, is common with PD. This may be accompanied by shorter steps and dragging feet.
- Stiff muscles may cause painful and reduced range of motion.
- Stooped posture, which affects balance.
- Automatic movements, such as blinking and smiling, might decrease.
- Mask face often results, which stems from reduced facial expressions and decreased eye movement.
- Monotone, soft, fast speech or slurring of words may be present.
- Micrographic, or small writing, may develop due to difficulty with writing and other fine motor tasks.
- Slow, shuffling, and hesitant gait.
- Freezing episodes that cause someone to stop in the middle of a movement.
The cause of PD has been identified as the break down of certain nerve cells called neurons. However, scientists do not know why this occurs. They know these neurons produce a chemical in your brain called dopamine. When dopamine levels decrease, abnormal brain activity occurs and leads certain hallmark symptoms to develop. Dopamine helps send messages to areas of the brain that control the motion of millions of nerve and muscle cells in the body. Genes are another factor that play a role, but only in rare cases when many family members have PD. Exposure to certain toxins such as polychlorinated biphenyls (PCBS) that were used in industrial processes or pesticides and herbicides can cause PD. Again, the risk of this occurring is small.
The presence of Lewy bodies, or clumps of specific substances within the brain, are markers that point toward PD on a cellular level. Furthermore, Lewy bodies contain a natural protein called Alpha-synuclein, which forms clumps that cells cannot break down and eliminate.
Hoehn-Yahr five stages
This system for diagnosis and staging of Parkinson’s was developed by Drs. Hoehn and Yahr in 1967. They are based on movement symptoms and a person’s ongoing self-care abilities and independence level.
- Stage 1 – This is the earliest stage of PD that involves mild symptoms without an impact on self-care. Tremors and symptoms influencing movement on one side of the body may be present along with some mild changes in facial expression, posture, and walking.
- Stage 2 – Symptoms worsen during this stage. This includes rigidity on both sides of the body and more obvious changes in walking and posture. Speech abnormalities may also be present. Someone with Stage 2 PD may be able to live alone, but daily self-care tasks will take more time and effort..
- Stage 3 – Symptoms such as loss of balance and coordination may result in falls. Movement is very slow. Someone in Stage 3 can still be independent, but symptoms will affect basic self-care activities like eating, grooming, dressing, and bathing.
- Stage 4 – Tasks become very challenging due to severe symptoms. Someone in Stage 4 may be able to stand without help, but needs a walker to get around. They will need assistance with all self-care tasks and household management. As a result, someone in this stage may no longer be able to live alone.
- Stage 5 – End stage PD, which is the most debilitating and advanced phase. Someone in Stage 5 may no longer be able to stand or walk due to significant muscle stiffness. They will either be bedridden or rely on a wheelchair to get around. This stage warrants round-the-clock care. New symptoms may develop such as delusions, hallucinations, mood disorders, and other non-motor symptoms such as impaired cognition, sleep disorders, changes in taste and smell, reading difficulty, quick fullness when eating, urinary urgency,and incontinence.
You may first be diagnosed with PD by your physician or an internist, who may refer you to a neurologist (a physician that diagnoses, treats, and manages conditions that affect the brain and nervous system, including PD, Alzheimer’s Disease, Multiple Sclerosis, Brain Tumors, and Stroke). There is no way to diagnose PD except through observations and questions. Observations may include noting symptoms such as tremors, muscle stiffness, lack of facial expression, ability to stand up from a chair, and inability to walk. Doctors may test your balance to see how quickly you can regain it if your equilibrium is disturbed.
Since there is no standard test for PD, this condition is diagnosed based on findings from a neurological exam and information reported by patients and caregivers. Parkinson’s Disease is a diagnosis made by excluding the possibility of other medical conditions and events, such as a stroke. Symptom progression and frequency varies from person to person.
Patients may receive medications after an individualized assessment of risks and benefits of their use and the age of the client upon diagnosis. In general, the goals of treatment for patients under 60 years old will include controlling impairing signs and symptoms of PD while protecting existing neurons. The primary medication choices for patients under the age of 50 include Eldepryl, Cocovri, and anticholinergic agents such as Artane and Cogentin. Patients in their 50s may require a dopamine agonist such as Mirapex in addition to or instead of Eldepryl to keep symptoms in check. If the desired response is still not achieved, a drug such as Sinemet should be added, followed by adjunctive Cocovri or anticholinergic therapy.
For patients who are 60 years and older, the primary goal is to improve existing functional impairments. For these patients, care is taken to avoid causing or worsening cognitive impairments. Sinemet CR is considered a first-line treatment for these patients. If this garners an inadequate response, providers can recommend a trial of immediate-release Sinemet and the addition of a dopamine agonist such as Mirapex once the maximum Sinemet doses are reached. Eldepryl, Cocovri, and anticholingeric agents such as Artane and Cogentin should be avoided because of their central nervous system side effects. These side effects can include insomnia, nervousness, lightheadedness, and seizures.
There are three surgical procedures used to treat Parkinson’s Disease. The first one is ablative or destructive surgery, which destroys areas of the brain affected by PD.This is intended to destroy abnormal electrical impulses or chemicals that cause PD symptoms. Stimulation and deep brain stimulation (DBS) involves implanting electrodes in the brain that can modify or block PD symptoms. Transplantation or restorative surgery consists of transplanting dopamine-producing cells from pig or human embryos into certain areas of the brain.