Parkinson’s Disease

Background

Parkinson’s disease (PD) is one of the most common neurological diseases, affecting at least 1.5 million people in the United States (American Parkinson Disease Association {APDA}, 2010). The average age of onset is about 59 years of age (APDA, 2010), and the likelihood of developing PD increases with age (National Institute of Neurological Disorders, 2008). It affects both men and women, particularly those over the age of 60 years (American Parkinson Disease Foundation, 2012). Parkinson’s disease was first described by Dr. James Parkinson as the “shaking palsy,” so named to describe the motor tremors witnessed in those experiencing this condition.

Parkinson’s disease is a degenerative, chronic disorder of the central nervous system in which nerve cells in the basal ganglia degenerate. A loss of neurons in the substantia nigra of the brainstem causes a decrease in the production of the neurotransmitter dopamine, which is responsible for fine motor movement. Dopamine is needed for smooth movement and also plays a role in feelings and emotions. One specific pathological marker is called the Lewy body, which under a microscope appears as a round, dying neuron.

Signs and Symptoms

Parkinson’s disease has no known etiology, though several causes are suspected. There is a family history in 15% of cases. Some believe a virus or environmental factors play a significant role in the development of the disease. A higher risk of PD has been noted in teachers, medical workers, loggers, and miners, suggesting the possibility of a respiratory virus being to blame. More recent theories blame herbicides or pesticides. An emerging theory discusses PD as an injury related to an event or exposure to a toxin versus a disease. Interestingly, coffee drinking and cigarettes are thought to have a protective effect in the development of PD (Films for the Humanities and Sciences, 2004).

The signs and symptoms of PD are many; however, there are four cardinal signs: bradykinesia (slowness of movement), rigidity, tremor, and gait changes such as imbalance or incoordination. A typical patient with PD symptoms will have some distinctive movement characteristics with the components of stiffness, shuffling gait, arms at the side when walking, incoordination, and a tendency to fall backward. Not all patients exhibit resting tremor, but most have problems with movement, such as difficulty starting movement, increased stiffness with passive resistance, and rigidity, as well as freezing during motion (NINDS, 2012). Advanced PD may result in Parkinson’s dementia.

Diagnosis

Diagnosis of PD is made primarily on the clinician’s physical examination and thorough history taken from the patient and/or family. Several other conditions may cause symptoms similar to PD, such as the neurological effects of tremor and movement disorders. These may be attributed to the effects of drugs or toxins, Alzheimer’s disease, vascular diseases, or normal pressure hydrocephalus, and not be true PD. There is no one specific test to diagnose PD, and labs or X-rays rarely help with diagnosis.

Treatment

Management of PD is generally done through medications. Levodopa, a synthetic dopamine, is an amino acid that converts to dopamine when it crosses the blood–brain barrier. Levodopa helps lessen most of the serious signs and symptoms of PD. The drug helps at least 75% of persons with PD, mainly with the symptoms of bradykinesia and rigidity (NINDS, 2008). One important side effect to note is hallucinations. A more common treatment, and generally the drug of choice, involves a medication that combines levodopa and carbidopa (Sinemet), resulting in a decrease in the side effect of nausea seen with levodopa therapy alone, but with the same positive control of symptoms, particularly with relation to movement. Patients should not be taken off of Sinemet precipitously, so it is important to report all of a patient’s medications if they are admitted to either acute or long-term care. Dopamine agnoists trick the brain into thinking it is getting dopamine. This class of medications is less effective than Sinemet, but may be beneficial for certain patients. The most commonly prescribed dopamine agonists are pramipexole (Mirapex) and ropinirole (Requip) (Parkinson’s Disease Foundation, 2012). Medications such as Sinemet show a wearing-off effect, generally over a 2-year period. During this time, the person must take larger doses of the medication to achieve the same relief of symptoms that a smaller dose used to bring. For an unknown reason, if the medication is stopped for about a week to 10 days, the body will reset itself and the person will be able to restart the medication at the lower dose again until tolerance is again reached. This time off from the medication is called a “drug holiday” and is a time when the person and family need extra support, because the person’s symptoms will be greatly exacerbated without the medication. The earliest drugs used for PD symptom management were anticholinergics such as Artane and Cogentin, and these medications are still used for tremors and dystonias associated with wearing-off and peak dose effects (Parkinson’s Disease Foundation, 2012).

There are many other treatments for Parkinson’s disease being explored. These include deep brain stimulation (DBS), with electrode-like implants that act much like a pacemaker to control PD tremors and other movement problems. The person using this therapy will still have the disease and generally uses medications in combination with this treatment, but may require lower doses of medication (NINDS, 2012). Thalamotomy, or surgical removal of a group of cells in the thalamus, is used in severe cases of tremor. This will manage the tremors for a period of time, but is a symptomatic treatment, not a cure. Similarly, pallidotomy involves destruction of a group of cells in the internal globus pallidus, an area where information leaves the basal ganglia. In this procedure, nerve cells in the brain are permanently destroyed.

Fetal tissue transplants have been done experimentally in Sweden with mild success in older adults and more success among patients whose PD symptoms were a result of toxins. Stem cell transplant uses primitive nerve cells harvested from a surplus of embryos and fetuses from fertility clinics. This practice, of course, poses an ethical dilemma and has been the source of much controversy and political discussion.

A more recent development includes the use of adult stem cells, a theory that is promising but not yet well researched. Cells may be taken from the back of the eyes of organ donors. These epithelial cells from the retina are micro-carriers of gelatin that may have enough cells in a single retina to treat 10,000 patients (Films for the Humanities and Sciences, 2004). In addition, cells modified from the skin of patients with PD can be engineered to behave like stem cells (NINDS, 2012). Both of these alternatives present a more practical and ethically pleasing source of stem cells than embryos.
Other research includes areas include those related to alternative therapies. For example, Tai Chi has been shown to be effective in improving balance and reducing falls for PD patients (NINDS, 2012). Rehabilitation units have been using Tai Chi for similar benefits in other patients with neurological deficits. Simple interventions such as using Wii games to promote activity and exercise may be explored. The role of caffeine in PD is also being examined. In a small randomized control study of 61 patients with PD, caffeine equivalent to 2–3 cups of coffee per day was given to subjects and compared with a control group of those taking a placebo. Those patients receiving the caffeine intervention showed little improvement in daytime sleepiness, but modest improvement in PD severity scores related to speed of movement and stiffness (Postuma et al., 2012). Further study with larger groups was recommended by the researchers.

Much of the nursing care in PD is related to education. Because PD is a generally chronic and slowly progressing disorder, patients and family members will need much instruction regarding the course of the disease and what to anticipate. Instruction in the areas of medications, safety promotion, prevention of falls, disease progression, mobility, bowel and bladder, potential swallowing problems, sleep promotion, and communication is important. Most of the problems seen as compli¬cations of PD are handled via the physician as an outpatient, but certainly complications such as swal¬lowing disorders as the disease progresses may require periods of hospitalization. When persons suffer related dementia in the final phases of the disease, they are often cared for in long-term care facilities that are equipped to handle the challenges and safety issues related to PD dementia. In ¬addition, access to resources and support groups is essential.

Adapted from Mauk, K. L., Hanson, P., & Hain, D. (2014). Review of the management of common illnesses, diseases, or health conditions. In K. L. Mauk’s (Ed.) Gerontological Nursing: Competencies for Care. Burlington, MA: Jones and Bartlett Publishers. Used with permission.