Young onset of Parkinson's
- Early-Onset Parkinson’s disease
- Young onset of Parkinson’s
- Juvenile Parkinson’s
Early-Onset Parkinson’s disease
Parkinson's disease (PD) has tradition¬ally been thought of as a disease of old age. It usually affects people in their 50s and 60s or even older, but some reports indicate that approximately 10% of all PD patients have symptoms before the age of 50.
Young onset of Parkinson’s
There appear to be some distinguishing features common to young-onset PD (YOPD), whether or not they indicate true PD. Most of these display predom¬inantly rigid, akinetic forms of the disease, 50% have no tremor on initial presentation and 50% never have tremor. In some cases in Japan, the tremor is described as being postural and irregular. There is a high incidence of dystonic phenomena, sometimes prior to the onset of any parkinsonian features. Autonomic disturbances appear to be less common than in late-onset cases and the same is true of cognitive disorders. In none of the cases reported in Japan was there any evidence of dementia.
Depression may occur more frequently and earlier in the course of the condition compared to older-onset patients. Issues of employment and marriage will be even more prominent.
There is evidence that the progression of the disease is slower YOPD and also that pathologically it does not differ from typical PD in the character or location of cellular abnormalities.
Researchers have found an association with lack of cigarette smoking and a history of severe head trauma. Some claim that a key to recognising YOPD is dystonia — often in one foot.
Although there are some differences, the clinical similarities in YOPD cannotbe ignored, but careful diagnosis is necessary to rule out dystonias and other motor disorders.
In the area of heredity, some controversy remains. The Japanese reports of a 42.5% heredity factor is distorted by the large number of very young patients who were treated when they presented with gait disturbances which were probably due to dystonia rather than Parkinsonism. Lima's studies (1980) in Brazil of 10 cases of YOPD show an incidence of affected relatives no higher than in classical idiopathic PD. A comprehensive study by Quinn et al (1987) found that only 4 out of 60 cases showed any familial connection. These were separated from the rest as "Juvenile parkinonism" to differentiate them from the YOPD cases where no familial connection was found.
While the cause remains uncertain, there is speculation that it may be the result of inherited tendencies and/or the accumulation of one or more environ¬mental toxins. Some studies have reported a more frequent rural back¬ground in YOPD.
Levodopa has a significant effect on symptoms in early onset parkinsonism. Results are seen within days, but side effects are also seen early, in some cases a few weeks after treatment has begun. Researchers in Yugoslavia and New York designed a study to look at the effects of levodopa on YOPD patients as opposed to older patients. The team matched 25 YOPD patients to patients who developed PD after age 40. They were matched on the amount of time they showed symptoms, levodopa dosage and duration of treatment. As a group, the young-onset patients had a greater prevalence of levodopa-induced dyskinesias and fluctuations, a difference that appeared as early as 6 months into therapy, although statistical significance was not reached until after 3 years.
The frequency of complications in YOPD patients remains greater even after 5 years of levodopa use, although intensity of dyskinesias was statistically equivalent in both groups. The median time it took to develop dyskinesias and fluctuations in YOPD patients was 3 years (for both), while in the older-onset patients it was 6 and 4 years respectively. Due to the greater risk of developing these complications, it is advisable to wait as long as possible before initiating levodopa therapy. Variation of dosing, timing and strength may be necessary. New medications are constantly being investigated and surgery is more common in early-onset PD. With YOPD, it is equally important to complement medication with regular exercise to keep physically fit, allowing more agility, alertness and better sleep.
Young Parkinson’s support groups are sometimes formed, depending on the need, and various newsletters are produced for YOPD people.
The first reported case of Juvenile Parkinson's was in 1875, by Huchard. The case was of a child of 3 with all the clinical features of PD. This was followed by a series of reports of isolated cases, showing PD symptoms, which showed strong familial signs. In 1910, Willige published a series of 14 early-onset cases, 6 of which were familial. His youngest case was 18 years of age. He believed that the patients were all affected by true PD. At this stage early onset of PD was being referred to as "Paralysis Agitans Juvenilis Familialis". Reports of Juvenile Parkinsonism have now appeared in medical literature frequently enough to provide a picture of a disease which has an onset of 3 30 years and which shows very similar clinical features to idiopathic PD.
The youngest reported case of PD is that of a 10-year-old girl from Oklahoma, who showed her first symptoms at age 2. It took doctors 7 years to diagnose PD, and she is now on an anti-parkinsonian drug regime that allows her to participate fully in school life and extra-curricular activities.
Following the advent of levodopa therapy, reports of Juvenile Parkinson's from 1960 emphasised the effects on the individual of drug therapy. These reports also showed cases of familial PD which were treated with levodopa. These responded, at least initially, in the same way as older patients who were on the same therapy. Martin, 1971, reported a case of two brothers who developed the disease at 10 and 19 respectively. They showed signs of stooped posture, shuffling gait, mask-like facial expression, resting tremor and rigidity. Both improved significantly with levodopa therapy but soon developed response fluctuations and abnormal involuntary movements. This peculiar phenomenon appeared in a matter of days and is the first mention in the literature of a characteristic pattern of treatment response in early-onset Parkinsonism.
One of the more recent reports of this disease was in 1981 by Clough et al. They reported a case of "Juvenile Parkinson's disease" as opposed to parkinsonism, believing that this case had all the requirements necessary to reach the unqualified diagnosis. Their case was a 22-year-old female with a 7-year history of tremor, rigidity and bradykinesia. She had no relatives with PD or with basal ganglia disorders. Investigations, including CAT scans, blood and urine tests, confirmed the clinical similarities to idiopathic PD. The response to levodopa was remarkable but as with other early onset cases abnormal movement began soon after treatment began. Based on their finding and their follow-up, the authors firmly believed that this case was an example of true idiopathic PD of very early onset.