No abstract

The study was conducted on 120 patients (76 men and 44 women) affected by idiopathic Parkinson's disease (IPD) responsive to L-dopa and observed for many years. Sixty had clinical onset between the ages of 20-40, representing 10.2% of our PD population; in the others the symptoms began after the 40th birthday. The two groups were matched for sex and length of illness. In all patients a diagnosis of IPD depended on history and clinical and neuroradiological findings. Clinical, pharmacological, evolutive, and epidemiological data were collected on all patients. Thirty-six patients from each group performed motor dexterity tests (reaction time to expected and unexpected stimuli) and cognitive tests (Wechsler Adult Intelligence Scale. Benton, Short tale, and Zazzo's speed and accuracy test). To assess the prevalence of dementia and the severity of psychiatric side effects of L-dopa administration, the 60 patients with early-onset PD were compared with 134 consecutive unselected PD patients. Five percent of early-onset PD patients had a family history of the disorder. Our study showed that early-onset PD does not differ fundamentally from the late-onset form except that the former is characterized by a more rapid establishment of the full-blown parkinsonian clinical picture and deterioration of the therapeutic efficacy of L-dopa, with an earlier appearance of side effects. The results of our neuropsychological investigations suggest that early-onset PD may be a "pure" form of extrapyramidal compromise with exclusively motor manifestations.

There are several reports of a defect of complex I in the substantia nigra (SN) of Parkinson's disease (PD) patients. To evaluate whether this is specific to dopaminergic neurons or the phenotypically relevant consequence of a widespread failure of the mitochondrial oxidative phosphorylation (OXPHOS) system, we measured respiratory enzyme activities in muscle homogenates from 16 PD patients and eight age-matched controls, and in muscle isolated mitochondria of six PD patients and six age-matched controls. We found no difference between the PD and control groups. In addition, we detected, by polymerase chain reaction, the mitochondrial DNA (mtDNA) "common deletion" (CD) in muscle specimens of 14 of 17 PD patients, but we obtained similar results in age-matched controls. In both groups, the amount of CD-specific deleted (delta) mtDNA ranged from 0.0% to 0.1%. Our data suggest that PD cannot be attributed to a multisystem decline of mitochondrial OXPHOS, and that lesions of muscle mtDNA in PD are likely due to normal aging. However, there was a remarkable accumulation of delta mtDNA in the SN of a PD patient and an age-matched control, suggesting that the SN is exquisitely sensitive to age-dependent damage of the mitochondrial genome.

SUMMARY Eighteen patients with Huntington's chorea were examined before and after neuroleptic treatment (haloperidol, pimozide, tiapride) to study the effect of such treatment on hyperkinesia and motor performance. Pimozide and haloperidol improved hyperkinesia; none of the drugs significantly affected motor performance. No correlation was found between the severity of hyperkinesia and motor performance scores, or between hyperkinesia and intelligence score, before and after therapy.Abnormal involuntary movements are a most distinctive clinical aspect of Huntington's disease. Striatal dopaminergic hyperactivity is supposed to cause abnormal involuntary movements in Huntington's disease.' Neuroleptic drugs, which act by inhibiting dopaminergic transmission at the synaptic level,2 are the accepted current therapy of abnormal involuntary movements in Huntington's disease.3 Their effect upon abnormal involuntary movements has been evaluated semiquantitatively.4-7 Impairment of motor performance"89 and functional disability7 are other aspects of Huntington's disease. These features have scarcely been considered in relation to neuroleptic treatment, since attention has been focused by different authors on hyperkinesia. Shoulson7 has observed that functional capacities of choreics were not influenced by neuroleptics. The relationship between abnormal involuntary movements and motor ability should be considered in this context.The aim of our study was to verify (1) the possible correlation between abnormal involuntary movements and motor impairment in Huntington's disease and (2) the effect of neuroleptic drugs on the same parameters.

A multicenter study has been conducted to determine the interobserver reproducibility of four of the most frequently used rating scales for Parkinson's disease: the Columbia University Rating Scale (CURS) and the Webster Rating Scale (WRS), both for assessing clinical signs; the Northwestern University Disability Scale (NUDS); and the Hoehn and Yahr staging. Four resident neurologists, inexperienced in the use of the four scales, independently examined 48 parkinsonian patients. The extent to which their assessments agreed was determined by calculating the Cohen k index after the scores had been recodified. The physicians' scores agreed substantially for the CURS and the Hoehn and Yahr scale, while those for the NUDS and the WRS agreed only moderately. Analysis of individual item scores within the scales suggests improvements that would offer greater interobserver consistency.