The performance on learning tasks of patients in the early stages of Parkinson's disease

It is known that in animals learning is disrupted by caudate lesions; but there has been no agreement about whether pathology in the basal ganglia causes a similar impairment in man. Nineteen patients in the early stages of Parkinson's disease were tested on two associative learning tasks and on the Wisconsin Card Sorting Task; and their performance was compared with that of patients with frontal or temporal lobe lesions. On the two associative learning tasks there was no overall difference between the Parkinsonian group and the controls. However, a minority of the Parkinsonian patients performed very poorly on these tasks; and it was noted that these tended to be the older patients.

Sequence ability in parkinsonians, patients with frontal lobe lesions and patients who have undergone unilateral temporal lobectomies

Patients in the early stages of Parkinson's disease were compared with patients who had sustained damage specific to either the frontal or temporal lobes and normal controls on a number of sequencing tests. These tests involved the reproduction of sequences of hand gestures, sequences tapped out on blocks, and sequences of digits. Only the groups with frontal lobe lesions or right temporal lobectomies were impaired on any of these tasks, though no group was impaired on all of the sequencing tasks.

Piracetam in the treatment of different types of myoclonus

Forty patients with different clinical and electrophysiological types of myoclonus were treated with piracetam (18-24 g per day, p.o.) alone, or with other drugs (clonazepam, sodium valproate, and primidone) in different combinations. Piracetam in monotherapy improved the electrophysiological abnormalities in patients with cortical reflex myoclonus, but had no useful clinical effect. Sixteen patients obtained benefit from piracetam when given in combination with other antimyoclonic drugs; improvement was dramatic in two patients, moderate in seven and mild in seven. All patients showing some response to piracetam had myoclonus of cortical origin; however, five other patients with similar cortical myoclonus failed to improve when piracetam was added. Tolerance was excellent and side effects were minimal and transient. It is concluded that piracetam probably has an antimyoclonic action, but its potential value as a therapeutic tool for disabling myoclonus requires further study.

Blepharospasm: a review of 264 patients

The natural history and response to different treatments have been evaluated in 264 patients with blepharospasm. The mean age of onset was 55.8 years and there was a female preponderance of 1.8 to 1. Dystonia elsewhere was found in 78% of patients, usually in the cranial-cervical region, and appeared to follow a somatotopic progression. A family history of blepharospasm or dystonia elsewhere was found in 9.5% of cases, which suggests a genetic predisposition. Ocular lesions preceded the onset of blepharospasm in 12.1% of cases. The response to drugs was inconsistent, although initial improvement was experienced by one fifth of patients treated with anticholinergics. Twenty-nine bilateral facial nerve avulsion operations were performed with benefit in 27 cases; but recurrences appeared in 22, on average one year after surgery. Botulinum toxin injections were performed in 151 patients. Significant improvement was achieved in 118 cases. Mean duration of benefit was 9.2 weeks. Transient ptosis and diplopia were the commonest side effects.

Antiparkinsonian activity of a single oral dose of PHNO

PHNO, a new D-2 agonist, was investigated in five patients with Parkinson's disease. In an acute, open, oral, dose-ranging study comparing benefit from single doses, 4 mg of PHNO was found to be equivalent to one tablet of Sinemet 25/250 mg. Adverse reactions were those anticipated for a dopaminomimetic agent. Because of its novel structure and apparent transcutaneous penetration, further studies on PHNO are desirable.

Young onset Parkinson's disease

We describe a personal series of 60 cases of parkinsonism with onset under the age of 40 years. Known causes for early onset of secondary parkinsonism, such as Wilson's disease or encephalitis, were excluded in every case. Two groups were identified: those with onset after the age of 21 in whom no hereditary factors could be ascertained (56 cases), and those with onset before 21 years all of whom had familial parkinsonism. In neither group have we found any association with prematurely grey hair, hypertension, diabetes, pernicious anaemia, or thyroid disorder. Among their families, we have not found any association with diabetes, pernicious anaemia, or thyroid disorder. We propose that cases of apparent idiopathic Parkinson's disease beginning between age 21-40 years should be called "young onset Parkinson's disease." Twenty percent of such patients in our series had at least one first- or second-degree relative in the same or antecedent generations with parkinsonism, but only 1.5% of their relatives at risk had parkinsonism, which is similar to the prevalence in the general population. Ten percent of these patients had at least one relative with essential tremor, but only 1.6% of their relatives at risk had tremor, which again was similar to the prevalence in the population in general. These patients with young onset Parkinson's disease responded well to levodopa therapy. However, dyskinesias and response fluctuations occurred early and frequently. The prevalence of dyskinesias and response fluctuations was strongly correlated with the duration of levodopa treatment, but not with the duration (or probably the severity) of the disease before levodopa therapy was commenced. The involuntary movements often were severe and frequently were diphasic. Despite long disease duration, the incidence of dementia in young onset patients aged less than 65 years was negligible. We believe that most, if not all, patients in this group have degenerative Lewy body idiopathic Parkinson's disease, representing the lower end of a skewed deviation for age of onset of this disease. We have so far failed to identify any additional environmental factor which may have accelerated disease onset in these patients. In contrast, cases of parkinsonism beginning before age 21 years were invariably familial. We proposed that they should be called "juvenile parkinsonism." All affected relatives with parkinsonism also had young disease onset, and all but one were siblings. None of four such patients seen by us has demented, and computed tomography (CT) scan has been normal in all four. We believe that most such patients have some form of genetically determined secondary parkinsonism.

Brain dopamine metabolism in patients with Parkinson's disease measured with positron emission tomography

L-[18F] fluorodopa was administered in trace amounts intravenously to healthy control subjects and to patients with Parkinson's disease. Striatal uptake of radioactivity was measured using positron emission tomography. The capacity of the striatum to retain tracer was severely impaired in patients compared to controls. This may reflect a reduction of striatal dopamine storage in Parkinson's disease. Patients showing the "on/off" phenomenon had an even greater decrease of striatal storage capacity.

Ipsilateral blepharospasm and contralateral hemidystonia and parkinsonism in a patient with a unilateral rostral brainstem-thalamic lesion: structural and functional abnormalities studied with CT, MRI, and PET scanning

A patient developed progressive right hemidystonia in childhood. Subsequently, left-sided blepharospasm, slurred and stuttering speech, and right-sided rigidity and bradykinesia, responsive to dopamine agonists, appeared. Investigation with computed tomography and magnetic resonance imaging (MRI) at age 43 years revealed a left-sided calcified rostral brainstem-thalamic lesion of uncertain aetiology. Although no structural lesion was seen in the striatal regions, L-[18F]-fluorodopa uptake was severely diminished in the left striatum but normal on the right. Dopamine receptor binding identified by [11C]-methylspiperone was in the normal range on both sides.

Preservation of the substantia nigra and locus coeruleus in a patient receiving levodopa (2 kg) plus decarboxylase inhibitor over a four-year period

A 72-year-old hypertensive man developed parkinsonism and was treated with Sinemet for 4 years but then died of a bronchial carcinoma. Necropsy revealed cerebrovascular disease and amyloid angiopathy. The substantia nigra and locus coeruleus were normal on light microscopy.

Brain energy metabolism and dopaminergic function in Huntington's disease measured in vivo using positron emission tomography

A 48-year-old man with typical Huntington's disease was investigated with computed tomography (CT) and positron emission tomography. Regional cerebral blood flow, oxygen extraction, oxygen and glucose utilisation, L-Dopa uptake, and dopamine (D2) receptor binding were measured using several positron-labelled tracers. CT showed slight atrophy of the head of caudate but no cortical atrophy, although distinct frontal lobe dysfunction was present on psychometric testing. Oxygen and glucose metabolism and cerebral blood flow were decreased in the striata and to a lesser extent in frontal cortex. Cerebral blood flow was in the low normal range throughout the remainder of the brain. A normal metabolic ratio was found in all regions, since the changes in glucose utilisation paralleled those in oxygen consumption. The capacity of the striatum to store dopamine as assessed by L-[18F]-fluorodopa uptake was normal, but dopamine (D2) receptor binding was decreased when compared to normal subjects.

The treatment of severe dystonia in children and adults

Twenty-three children (aged less than 18 years) and 17 adults with severe widespread dystonia were treated with high doses of benzhexol (up to 130 mg daily introduced slowly over many weeks). Children tolerated higher doses (median 30 mg/day) than adults (median 20 mg/day). 52% of the children gained useful benefit, many (43%) without unwanted side effects. Such an approach was less successful in adults; 41% gained benefit, but only 35% had no side effects. Twelve adults with severe axial dystonia, and two children with life-threatening generalised dystonia were treated with a combination of a low constant dose of tetrabenazine to which were added pimozide and benzhexol as necessary. The dose of tetrabenazine was aimed at 75 mg daily; pimozide was increased (6 to 25 mg/day) until the dystonia was relieved or Parkinsonism and other side-effects prevented further increments; if necessary benzhexol (6 to 30 mg/day) then was added to control side-effects and to provide additional benefit. 75% of the adults with severe axial dystonia, and one of the two children with life threatening generalised dystonia gained useful benefit from this regime. It is concluded that high dose benzhexol is the present first treatment of choice for children with severe dystonia, and is worth a try in adults but with less expectation of success. When benzhexol treatment alone fails in adults with severe disabling axial dystonia, or in children with life-threatening generalised dystonia, combined therapy with tetrabenazine, pimozide and benzhexol may give valuable symptomatic relief.

Control of on/off phenomenon by continuous intravenous infusion of levodopa

In 10 parkinsonian patients with severe, chaotic clinical response fluctuations, oral levodopa treatment was replaced by continuous intravenous infusion of levodopa (with orally administered benserazide). Four patients were also given levodopa infusions in addition to their usual oral treatment. All patients remained continuously mobile and ambulant during the infusions. Side effects were minimal, except in two patients with diphasic dyskinesias whose abnormal movements were consistently suppressed by a further increase in the rate of levodopa administration, only to return after an interval. If a soluble nonacidic dopamine replacement drug can be developed for continuous subcutaneous infusion, "brittle" parkinsonians may be chronically controlled by portable, minipump technology.

A double blind trial of sulpiride in Huntington's disease and tardive dyskinesia

Eleven patients with Huntington's disease and nine patients with tardive dyskinesia participated in a randomised double-blind crossover trial of sulpiride (as sole antidopaminergic therapy) versus placebo. Although functional improvement was not seen in Huntington's disease patients, sulpiride reduced movement count and total dyskinesia score in both conditions. Sulpiride differs pharmacologically in several respects from conventional neuroleptics, and has not been convincingly shown to cause tardive dyskinesia. Among currently available treatments, it may therefore be considered a drug of choice for treatment of tardive dyskinesia.

Alterations in cognitive performance and affect-arousal state during fluctuations in motor function in Parkinson's disease

Sixteen patients with idiopathic Parkinson's disease were selected who were all showing severe fluctuations in motor function ("on-off" phenomenon). Measures of cognitive function and of subjective affect/arousal state were taken on two occasions, once when "on" and once when "off". Twenty-five matched normal controls were also assessed on the same measures. Results revealed, on the average, a drop in cognitive function plus an adverse swing in affect/arousal state, in the patient group in the "off" condition, compared to the levels when "on". Analysis of the data suggested that the main factor associated with cognitive function when "off" was not the severity of disability but the level of affect/arousal. The fluctuations in cognitive function found tended to be mild relative to the severe changes in motor ability, and were present in only a proportion of patients.

L-Dopa methyl ester--a candidate for chronic systemic delivery of L-Dopa in Parkinson's disease

Continuous intravenous infusions of L-Dopa as a treatment for response swings in Parkinson's disease are limited by the insolubility and acidity of L-Dopa. Its methyl ester is a soluble neutral derivative that might be of benefit to these patients, and is examined in the present study in behavioural and biochemical animal models. On intraperitoneal or subcutaneous administration to mice L-Dopa methyl ester was equivalent to L-Dopa in reversing reserpine-induced akinesia and producing contraversive circling behaviour in rats with a 6-hydroxydopamine lesion of the medial forebrain bundle. On oral administration the methyl ester was more active. The administration of L-Dopa or the methyl ester produced equivalent changes in striatal and mesolimbic dopamine, homovanillic acid, and 3,4-dihydroxyphenylacetic acid metabolite levels. We suggest that systemic or subcutaneous infusion of L-Dopa methyl ester to patients who experience response fluctuations may provide a means of maintaining mobility.

Health hazards of operating video display terminals

Today, millions of employees work on video display terminals (VDTs) and their numbers are growing. Concern over the health effects of operating VDTs is also growing as the hazards of working on these terminals are identified. This article discusses four major hazards associated with VDTs. Solutions to control these hazards and decrease employee symptoms are offered. Utilizing a theoretical framework of stress and stress reduction, solutions are presented, based on the multi-disciplined background of the occupational health nurse practitioner.

Concentrations of GABA and other amino acids in CSF from torsion dystonia patients

Free amino acid concentrations were measured by conventional amino acid analysis, and gamma-aminobutyric acid (GABA) concentrations were determined, by an ion-exchange fluorometric technique, in CSF specimens from 16 patients with torsion dystonias and in CSF from a large number of control subjects. The mean CSF GABA concentration of the dystonia patients (97 +/- 11 nmol/L) did not differ significantly from the means for CSF GABA in two groups of adult control subjects. Mean concentrations of all commonly determined amino compounds were normal in the CSF of torsion dystonia patients, except for ornithine, which was modestly but significantly reduced.

Pergolide in late-stage Parkinson disease

Twenty-six patients with late-stage Parkinson disease were given 0.4 to 15 mg of pergolide mesylate daily in addition to, or as replacement for, levodopa or bromocriptine therapy. Despite treatment with individually determined optimum doses of levodopa, bromocriptine, and anticholinergics, they had shown response failure or fluctuating response. Forty percent (11 patients) were unable to tolerate pergolide. Nausea and vomiting, somnolence, and psychiatric disturbances were the most frequent side effects. Eleven of the remaining patients improved on pergolide, 2 were unchanged, and 2 were slightly worse. Among the patients who benefited, pergolide improved dose-related response fluctuations more than non-dose-related fluctuations, with a reduction in number and duration of "off" periods and improvement in quality of sleep and early morning akinesia but little change in freezing episodes. Despite treatment failure in many cases, pergolide is at present the best available drug for specific late-stage management problems.

Complicated response fluctuations in Parkinson's disease: response to intravenous infusion of levodopa

The cause(s) of response fluctuations in patients with Parkinson's disease treated chronically with levodopa is unknown. In some subjects it is difficult to establish a clear relation between levodopa dosage and timing and the resultant clinical effects. This may be due to variation in the degree of absorption of the drug, and in the latency from ingestion to peak plasma level and from plasma peak to central action. In one patient illustrated, careful analysis of "on-off" charts reveals an underlying pattern of end-of-dose deterioration at a time when history alone suggested a completely random response to levodopa. In three patients replacement of oral treatment by continuous intravenous infusion of levodopa, with oral administration of decarboxylase inhibitor, produced a prolonged and stable clinical response, even when ambulant. This response was maintained not only in one subject showing predictable fluctuations, but also in two subjects with unpredictable response to oral treatment. The addition of intravenous levodopa infusion to the usual oral regimen of the first patient when she was experiencing prolonged "off" periods despite generous doses of oral levodopa with decarboxylase inhibitor also produced stable clinical benefit. These results suggest that, even in patients with complicated response swings, central dopamine receptors remain available for stimulation providing levodopa can be delivered at a constant rate and in an adequate quantity to the brain.

Bromocriptine and domperidone in the treatment of Parkinson disease

In a single-blind trial of therapy in 20 patients with idiopathic Parkinson disease, domperidone prevented nausea and vomiting induced by bromocriptine without diminishing beneficial central effects. Combination of the two drugs permitted rapid increase in bromocriptine dosage from 22.5 mg per day to 148 mg per day, with 71% mean clinical improvement over baseline score; continuing efficacy of the regimen was evident for a mean follow-up of 2 months.

Bromocriptine in Parkinson's disease: a study of cardiovascular effects

Blood pressure and pulse rate were studied in 20 Parkinsonian patients on no treatment, and during treatment with bromocriptine (mean dosage 148 mg/day) as the sole anti-Parkinsonian therapy. The drug was shown to reduce erect systolic and diastolic and supine systolic blood pressure and to increase erect pulse rate, in a predictable dose-dependent manner. The occurrence of episodes of significant postural hypotension was less predictable and was a transitory phenomenon in all patients. Peripheral dopamine receptor blockade with domperidone did not alter the findings, suggesting that the principal mechanism for these cardiovascular effects is a central dopaminergic one.