Parkinson’s disease is a neurological disorder which is primarily diagnosed in people aged 50 and above. This degenerative disease affects the muscular movement, creates tremor and increases posture rigidity. First explained in 1817 by James Parkinson, this disease is prevalent throughout the world. In the United States as well as the UK around 2% of the elderly population is afflicted by this neurological disorder. In the U.S. alone there are around 1 million patients and every year 50,000 new cases are diagnosed with Parkinsonism and as a nation with a high percentage of elderly and aging population the figures may increase rapidly in the near future. A brief overview of the etiology, symptoms, treatment, patient care and education, would help us better understand the disease condition and its management.
Pathophysiology of Parkinson’s Disease
Parkinson’s disease is a disorder of the motor structures in the basal ganglia region of the brain. One of the observed features of this disease is the degeneration of the neurons in the ‘substantia nigra’ which are responsible for the production of dopamine. Dopamine is one of the important neurotransmitters of the body which plays a critical role in controlling the physical movements. A balance between acetylcholine (another neurotransmitter) and dopamine is essential for maintaining the normal motor functions of the body. So a decrease in dopamine producing neurons creates an imbalance in dopamine – acetylcholine ratio resulting in the manifestation of symptoms. The loss of pigmentation in the ‘substantia nigra’ region indicates the damage to the dopaminergic neurons. However the existence of lewy bodies and damage to other neuronal regions are also observed. [Jeff Blackmer]
The exact cause for the onset of Parkinson’s disease has not yet been clearly established though a combination of factors have been identified as being responsible for the disease condition. Various theories are put forward to explain the etiology of the disease such as ‘Accelerated Aging’, ‘Oxidative Stress’, ‘Environmental and Neurotoxins’ and finally the theory of ‘Genetic Predisposition’. It is generally observed that with increasing age there is a gradual decline in the dopaminergic neurons in the substantia nigra region of the brain. Experts suspect that in subjects with Parkinson’s disease this normal aging process is accelerated in combination with some kind of stress related ischemic insult to the brain.
The currently widely accepted factor however is the oxidative theory which explains the role of the free radicals in the destruction of the neuronic cells. Dopamine is metabolized in the presynaptic neuron by the enzyme monoamine oxidase resulting in the production of Hydrogen peroxide which further reacts (with iron) to form the harmful hydroxyl free radicals which can inflict damage to the neuronic cells. Environmental toxins such as cyanide, methanol, organic solvents and industrial metals like zinc, manganese, etc. have also been identified to have neurotoxic effect. Synthetic meperidine also known as MPTP which is used as an alternative to heroin is now well-known for its neurotoxic effect. Genetic predisposition is greater in families with a history of the disease. Studies have confirmed a greater incidence of around 16% as against 4% in other control groups. [Jeff Blackmer]
Symptoms and Complications
The typical symptoms of Parkinson’s disease include tremor, stooping posture, muscular rigidity. All voluntary movements get slowed down and the patient becomes bradykinetic. In advanced stages of the disease patients may experience frequent falls due to the postural imbalance. One common symptom is the ‘resting tremor’ which is observed in 70 to 80% of the patients. Micrographia or the pattern of small handwriting is also identified in patients with Parkinson’s disease. Constipation is a common feature of this disease. The thinking process is also affected significantly and many patients experience slowness of thought or what is called in the medical parlance as ‘bradyphrenia’. There is a general loss or gradual impairment of cognitive abilities and in advanced stages of the disease dementia manifests in one third of the patients. [David Nicholl]
Autonomic dysfunction, Depression and ‘Cardio-pulmonary impairment’ are the potential complications in patients with Parkinson’s disease. ‘Orthostatic hypotension’ or the condition of ‘low blood pressure when standing’ is observed in advanced stages. The stooped posture of patients will severely restrict the lung capacity leading to breathing complications. Left unattended pulmonary function can be severely affected due to kyphosis. (bent back) Urinary incontinence and intestinal absorption problems may also occur necessitating specific treatment. There is a positive relation between depression and Parkinsonism and in at least 30% to 50% of patients depression is found to be a co-existing condition. Dysphagia is again a severe complication and the patient may even require a feeding tube. [Jeff Blackmer]
Medical treatment of Parkinson’s disease is broadly divided under two main categories namely surgical and non-surgical (pharmacological) treatments. Advancements in stereotactic surgical techniques such as thalamotomy, pallidotomy and deep brain stimulation have created new breakthroughs in the treatment of Parkinson’s disease. Of these thalamotomy and pallidotomy are considered as destructive surgeries in that they involve creating lesions in the brain segments to limit the effect of anomalies and improve the motor functions. Thalamotomy is proven to be greatly effective in arresting or relieving tremor which has responded poorly to drugs. Similarly pallidotomy procedure is effective in controlling the anomalies in the ‘globus pallidus’ from affecting the motor functions. Deep brain stimulation on the other hand is a reversible procedure unlike the above mentioned destructive surgeries. Stimulation of the globus pallidus and the lateral thalamic nuclei have successfully controlled tremor in around 80% of the patients. Apart from these, clinical trials of transplantations such as Adrenal medulla, xenograft and Fetal mesencephalon grafts have received mixed success and much work needs to be done in this area. [Jeff Blackmer]
Pharmacological treatment involves the use of anticholenergic drugs to restore the balance in the acetylcholine – dopamine ratio and other forms of anti-parkinsonian drugs like dopamine agnostics, dopaminergic agents etc. Benzhexol is an example of anticholenergic drug which has been successful in controlling of tremor symptom. Similarly Selegiline is an example of MAO-B inhibitor which reduces the action of the enzyme monoamine oxidase which metabolizes dopamine. Benztropine and amantadine have strong dopaminergic effects. Levodopa (L-dopa) is another important drug which is used as a replacement for the dopamine. Recently COMT inhibitors (catechol-O-methyltransferase inhibitors) have become more widely used along with L-dopa to slow down the lateral metabolism and prolong the effect of the L-dopa. [David Nicholl]
Patient Education and Care (Nursing Intervention)
The debilitating effects of Parkinson’s disease, requires efficient nursing care. Nurses play an important part in educating the patient about the long-term effects of the disease, the possible complications, and side effects of the continuous use of medicines and in assisting them to successfully manage the symptoms. The positive therapeutic effects of a loving and supportive nursing care cannot be understated. Especially for very old people who require long-term care, nurses play a vital role in overseeing the nutritional interventions, studying the functional status and the daily progress and in effectively managing other complications (like Orthostatic hypotension, Dysphagia) which are common in advanced stages. [Suzanne C, 1983]
Since constipation is a major problem and it may lead to other dangerous complications such as volvulus, and paralytic ileus nurses have to stress the importance of preventive bowel care. Mobility of the patients in the advanced stages is severely restricted with acute bradykinesia and there is also an increased risk of fractures. In such cases nurses and other caregivers can encourage the use of appropriate assistive devices. Above all, the intake of anti-parkinsonian drugs may have side effects such as confusion, hallucinations, and other forms of drug psychosis. Nurses are the first persons to notice any adverse reaction to drugs, worsening symptoms or other behavioral changes. Under these circumstances they can adjust the dosage of the drugs to restore normality in thinking though it may temporarily compromise on the mobility of the patient. [Susan M. Calne] Skilled nursing is essential for good symptomatic management and there is no question of doubt that nurses have an indispensable role in delivering quality care in a long-term patient care setting.
1) Dr. David Nicholl (2003, OCT 19), “Parkinson’s Disease,” MedWeb
Retrieved June 4th 2004, at http://medweb.bham.ac.uk/http/depts/clin_neuro/teaching/tutorials/parkinsons/parkinsons1.html
2) Jeff Blackmer, MD (2004, May 20), “Parkinson Disease,” eMedicine
Retrieved June 4th 2004, at http://www.emedicine.com/pmr/topic99.htm
3) Suzanne C. O’Connell Smeltzer EdD, RN, FAAN Brenda G. Bare RN, MSN,
Medical-Surgical Nursing” Brunner & Suddarth, 10th Edition pg 1979-1983
4) Susan M. Calne, Ajit Kumar, “Nursing Care of Patients with Late-Stage
Parkinson’s Disease” [Electronic Version]. Journal of Neuroscience Nursing,
October 2003, Volume 35, Number 5
Retrieved June 4th 2004, at http://www.aann.org/ce/pdf/jnn10_03a.pdf