What is Parkinson's
What is Parkinson disease?
Parkinson’s occurs when certain nerve cells (neurons) in a part of the brain called the substantia nigra die or become impaired. Normally, these cells produce a vital chemical known as dopamine. Dopamine allows smooth, coordinated function of the body's muscles and movement. When approximately 70% of the dopamine-producing cells are damaged, the symptoms of Parkinson disease appear.
Parkinson's disease is a progressively degenerative neurological disorder which affects the control of body movements.
Symptoms result from the progressive degeneration of neuronal cells located in the substantia nigra. This causes a deficiency in the availability of dopamine; a chemical neurotransmitter (messenger) necessary for the production of smooth controlled movements.
The symptoms of Parkinson's disease appear when about 70% of dopamine producing cells cease to function normally. Symptoms develop slowly and gradually progress over years, but are greatly helped by drug treatment.
The presentation of symptoms varies greatly between individuals diagnosed and no two people will be affected in the same way. The three symptoms used for diagnostic purposes are:
Tremor, (shaking, trembling) is the most well known symptom of PD, but is absent in one third of people when the condition is first diagnosed. Tremor usually begins in one hand and the spreads to the leg, before crossing to the other side. It may also be felt internally. Typically it is most noticeable at rest and when stressed or tired and disappears during movement and when asleep.
Rigidity or stiffness of the muscles is a very common early sign of PD whereby the muscles seem unable to relax and are tight, even at rest. You might feel that your muscles will not do what you want them to do. Rigidity may be experienced through the entire range of movement of a joint (called 'lead pipe rigidity') or just in parts (called 'cog-wheel rigidity).
Bradykinesia (slowness of movement) occurs because the brain is not able to control smooth and delicate movements.
- Leads to a lack of spontaneous activity eg. arm swing diminishes.
- Fine motor coordination is reduced eg. handwriting becomes smaller.
- May lead to freezing or periods of immobility.
In some patients include pain and discomfort in an arm or leg, anxiety and depression, slowness of thinking and memory problems and tiredness and disturbed sleep. Constipation is common and bladder problems, especially a tendency to pass water more frequently and with more urgency, may occur. Sexual difficulties may trouble some people. Speech and swallowing problems tend to become more of a problem later in the illness.
At present there is no known cause and therefore the illness is termed; "idiopathic". It is not considered to be genetic though 10% of cases have a familial incidence.
Predominantly those in the middle to later years i.e 50-75 are affected, though up to 20% of people are diagnosed between the ages of 30 and 50.
Ten per cent of people are diagnosed before the age of 45 years of age. Approximately 20,000 people are diagnosed with Parkinson's disease in Victoria.
Approximately 1,000 new cases are diagnosed in Victoria per annum, or an average of 19 every week of the year.
It is difficult to diagnose Parkinson's disease as there are no pathological tests or identifying markers to confirm a diagnosis. Diagnosis is based on a progressive history of deterioration in function and clinical impression.
Rate of Progression:
Each person is affected differently and therefore the rate of progression varies greatly between individuals. The illness progresses at a very slow rate and longevity of life is not shortened. Treatment alleviates symptoms though does not halt or slow the progression of the illness.
Parkinson's disease will affect the individual for the remainder of their life with increasing severity as the illness progresses.
Impact on the individual:
functional mobility and the ability to perform all activities of daily living independently becomes more difficult. Unpredictable fluctuations in motor movement and "freezing" (inability to initiate movement) can occur. Tremor or other physical abnormality of movement causes embarrassment and can socially isolate the individual.
Bodily Functions -
general slowing of muscle activity can lead to problems with temperature regulation, ingestion and digestion of food/fluids, elimination, sleep and sexual relationships.
every person with Parkinson's experiences an increased level of anxiety related to the unpredictable nature of motor fluctuations and an uncertain future. It is estimated that approximately 90% of people with Parkinson's also suffer from depression.
difficulties with communication eg. mask-like face, soft voice, diminished non-verbal gestures, and indiscernible hand-writing, limit the person's ability to socialise. Increased physical incapacitation, a growing dependence on others, and negative stigma about the illness from the community all contribute to social isolation.
during the advanced stages of the illness, some people are affected by dementia associated with the degenerative processes of Parkinson's Disease, although most retain intellectual functioning. Difficulty with tasks involving sequential steps, or activities which require use of short term memory are reported.
Impact on the family:
Parkinson's disease can affect a persons role within a family, and therefore alter the roles and responsibilities of other family members. Leisure activities, household chores, driving, and the capacity to maintain current income can be disrupted or limited. The socially isolative effect of Parkinson's can limit the social activities of the whole family.
At present Parkinson's disease is incurable, however drug therapy can alleviate symptoms. The main form of treatment is medication, with the main objective of restoring the deficiency of dopamine. Two kinds of drugs are used: those able to cross the blood-brain barrier and be converted into dopamine by the brain; and those able to effectively stimulate the dopamine receptors of the brain.
Drug therapy is complicated by side effects which often occur as a result of long-term use of anti-Parkinsonian medication (medication has a maximum benefit of 5 - 10 years). These side effects can be as disabling as the condition itself. One of the most distressing side effects is the 'on-off' syndrome, or disabling fluctuations in ability. This side effect is greatly misunderstood by many health professionals who often label a person who is 'off' as 'difficult' or 'unco-operative'.
Neurosurgical management of Parkinson's disease using surgical techniques has been utilised since the 1940's though its popularity waned with the introduction of levodopa medication in 1967. Improved imaging techniques and the need to arrest disabling long term effects of medication has seen renewed interest in this form of treatment. This method of treatment is still somewhat experimental.
Because of the individual complex nature of Parkinson's disease, management required a wholistic approach which takes account of the whole of the affected persons life.
The diagnosis of Parkinson's disease is often a shattering experience both for those diagnosed and their families. It needs to be given in a sensitive way so as to allow people time and space to come to terms with the diagnosis, and encourage them to seek further information and advice as they need it.
There is no optimum drug treatment for Parkinson's disease. Each person must be prescribed a specific regimen to suit his or her particular needs, both in terms of timing and dose. This will often involve a 'cocktail' of different drugs available to ensure the best possible effects for the patient. It is important to note again that drug treatment does not cure Parkinson's and so the disease continues to progress under treatment. As the disease progresses, the individual regimen needs to be reviewed and, when necessary, modified.
Early access to a multidisciplinary team is essential. Multidisciplinary assessment can be made of the person's abilities, potential difficulties can be identified and coping mechanisms put into place before problems start. The multidisciplinary team may include physicians, dietitians, chiropodists, counsellors, psychologists, specialist nurses and volunteers. Continuity of care, particularly with the involvement of so many different professionals, is very important.
Many carers receive no training, guidance or instructions on how to cope with someone who has Parkinson's disease. Carers may experience a whole range of feelings; guilt, anger, resentment, fear and bereavement. They need general information and practical advice, most importantly they need emotional support.