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CURRENT SCIENCE REVIEWS By Joe Bruman May 1998 Part 1 of 3 Heikkila V-M et al; J Neur N'surg Psych 1998;64:325-330: Evidently, control of driver licenses in Finland is much stricter than in the U.S. Authors gave psychological and psychomotor lab tests and a standard driving test to 20 PD patients, 3 of whom had recently caused accidents, and 20 matched controls. Results were compared and driving ability evaluated by a neurologist, a psychologist, a vocational rehabilitation counsellor, a driving instructor, and patients themselves. PD patients' driving ability was greatly impaired, but their self-assessment was much too optimistic. The PD group equaled controls in highway driving, but did poorly in an unfamiliar city with heavy traffic. Authors mention, but don't allow for, compensation by less-skilled or handicapped drivers who avoid such situations. [Articles like this no doubt will lure license officials to pre-judge any applicant with PD, threatening the independence of driving one's own car.] Deuschl G, Goddemeier C; J Neur N'surg Psych 1998;64:320-324: They found blink rate to be a weak diagnostic tool for several CNS disorders. Incidentally, in PD the reflex blink is hyper-reactive. Kimpara T et al; J Neur N'surg Psych 1998;64:416: They describe recent inconclusive search for a gene mutant that is common to both idiopathic and familial PD. Morrish P et al; J Neur N'surg Psych 1998;64:314-319: By successive PET scans with fluorodopa marker on 32 PD patients, they looked for correlation with clinical progression. Results by backward extrapolation indicate a mean preclinical period of only 3 years, compared with previous estimates of up to 50 years, and raising doubt about validity of PET studies for that purpose. Monza D et al; Arch Neur 1998;55:372-378: A battery of general neuropsychological tests on patients with PSP, MSA, or PD showed congnitive and motility impairment. Kopyov O et al; Exp Neurology 1997;146:536-545: Among 13 successful fetal tissue grafts in PD patients, 6 got 20 cubic mm of tissue, 7 got 24, and the latter group had significantly better symptomatic improvement. Kopyov O et al; Exp Neurology 1998;149:97-108: As a preliminary safety test, they did fetal tissue transplants in three Huntington's Disease patients, with no serious effects. Clinical improvement was variable but encouraging, for use of the transplant technique against other diseases besides Parkinson's. Davie C; Mov Disord 1998;13:1-2: The new techique of Magnetic Resonance Spectroscopy (MRS) is to Magnetic Resonance Imaging (MRI) as color photography is to black- and-white. Mapping concentration of specific metabolic compounds as well as tissue density in the living brain can distinguish PD from other neurodegenerative diseases such as MSA or PSP, and help in study of the disease process. Holmgren B et al; Mov Disord 1998;13;70-77: In a survey including 19 PD patients, 12 with progressive supranudclear palsy (PSP) and 10 with multiple system atrophy (MSA), concentration in the cerebrospinal fluid (CSF) of a principal protein component of neural axons was higher in the latter groups, reflecting the axonal degeneration of those diseases and suggesting CSF analysis as a diagnostic tool. CURRENT SCIENCE REVIEWS By Joe Bruman May 1998 Part 2 of 3 Nguyen JP et al; Mov Disord 1998;13:84-88: Facial pain and severe left arm action tremor following surgery were relieved by chronic stimulation of the motor cortex. The stimulation parameters most effective for pain and tremor were different, suggesting that pain and tremor mechanisms also differ. Riedl A et al; Mov Disord 1998;13:212-220: Mutations of the gene CYP2D6 have been suspected as predisposing to PD, but a survey of literature and recent studies indicates otherwise. Banati R et al; Mov Disord 1998;13:221-227: Elaborate postmortem search for signs of apoptosis in dead neurons of the substantia nigra of 10 PD patients failed to find any. Pearce R et al; Mov Disord 1998;13:234-241: Either bromocriptine or ropinirole alone in MPTP monkeys improves motor symptoms with less dyskinesia than the equivalent dosage of levodopa. However, if use of either agonist follows treatment with levodopa, it elicits dyskinesia comparable with that of levodopa. So they conclude that PD treatment should begin with an agonist. Dodel R et al; Mov Disord 1998;13:249-254: The cost of PD care in Great Britain is estimated at 383 million pound sterling/year. Among 409 PD patients of a German clinic, mean daily cost per patient of drugs alone ranged from DM6.60 to DM74.30, depending on stage and severity of the disease. Dietz V, Colombo G; Mov Disord 1998;13:255-261: By electromyographic (EMG) sensors they tested the effect of body load on the gait of PD patients. The lower leg flexor muscle activity is independent of load, while that of the extensor muscle is load-sensitive, suggesting that decreased extensor load reflex mechanism contributes to gait impairment in PD. Lagopoulos J et al; Mov Disord 1998;13:262-267: Comparing event-related potentials [via electrodes on scalp] of 15 PD patients and 50 normal controls, they found the PD group deficient in N200 amplitude at several sites in the central and temporal regions, possibly reflecting impaired response selection. Antonini A et al; Mov Disord 1998;13:268-274: Idiopathic PD (IPD)is hard to distinguish from other, atypical parkinsonian disorders (APD) by clinical signs alone, but Positron Emission Tomography (PET) mapping of glucose metabolism effectively sorted out 56 IPD and 48 APD patients. Dethy S et al; Mov Disord 1998;13:275-280: With levodopa responsiveness as tentative discriminant, PET mapping of glucose metabolism (using 18F fluorodeoxyglucose marker) was able to distinguish 9 cases of presumed PD from 10 of striatonigral degeneration. Louis E et al; Mov Disord 1998;13:287-293: Although essential tremor is common, diagnosis is difficult. To find a reliable protocol, they had two movement disorder specialists examine 35 previously diagnosed ET patients and 40 matched controls, using a standardized Tremor Interview and a videotaped Tremor Examination, in a blind trial. From the excellent agreement they conclude that the protocol is a reliable one. CURRENT SCIENCE REVIEWS by Joe Bruman May 1998 Part 3 of 3 Syed N et al; Mov Disord 1998;13:336-338: Late-stage PD patients with severe motor fluctuations may resort to an enteral infusion pump, to maintain steady availability. But the inconvenience and discomfort of the apparatus are discouraging, and authors would like development of a less cumbersome system. Marsden C; Clin Neuropharm 1994;17:Supp 2:S32-S44: [This and next 4 items belatedly appeared in Medline] Reviews problems of long-term levodopa therapy for PD: fluctuations, dyskinesias, toxicity, loss of efficacy. Tolosa E, Valldeoriola F; Clin Neuropharm 1994;17:Supp 2:S19-S31: Fluctuations in mid-stage levodopa therapy for PD are usually due to "wearing-off" or "end-of-dose" effects. Corrective strategies include controlled-release levodopa, MAO-B inhibitors [Deprenyl], COMT inhibitors, and various "direct" dopamine agonists. Calne D; Clin Neuropharm 1994;17:Supp 2:S14-S18: Best options for intial treatment of early-stage PD aren't agreed on but include five categories of drugs, for symptomatic relief: anticholinergics, amantadine, selegiline, dopamine agonists, and levodopa. He prefers levodopa, with a decarboxylase inhibitor to prevent nausea [e.g., Sinemet]. Stocchi F et al; Clin Neuropharm 1994;17:Supp 2:S7-S13: Most fluctuations after chronic dopaminergic treatment reflect decline of levodopa availability, usually countered by bigger or more frequent dosage. In a 5-year trial they compared continuous subcutaneous lisuride infusion in 18 PD patients, against 20 given conventional oral levodopa. All complications worsened in the Ldopa group, while in the lisuride group only dyskinesia got worse. Sinemet CR reduced fluctuation but was slow to act, so they recommend a combination of CR and standard Sinemet. Sage J, Mark M; Clin Neuropharm 1994;17:Supp 2:S1-S6: Pharmacokinetics of Sinemet CR are affected by absorption (gastric emptying, solubility, uptake in gut); distribution (gut-blood, blood-brain transport); and biotransformation (by various enzymes). Sinemet CR has the advantage of lower and longer peak effect. Laine K et al; Clin Neuropharm 1997;20:419-433: In a short double-blind trial on 24 healthy volunteers, they studied interaction of the MAO-B inhibitor selegiline and the widely used selective serotonin reuptake inhibiting antidepressant citalopram [brand name unknown], finding none of importance. Ben-Shlomo Y et al; BMJ,18 April 1998:1191-1196: Continuing the long Eldepryl debate, the UK group presents new data implying that the excess mortality risk may be less but still there, and that the benefits for PD, if any, are minor. An editorial summary and comment appears in the same issue. Golbe L; Lancet, 4 April 1988:998-999: Microelectrode recording and stimulation, magnetic resonance imaging, rapidly growing skill and experience have made pallidotomy much safer and more effective than when it was first tried about 50 years ago, but it still should be a last resort, for PWP who are not demented and who do respond to levodopa. It doesn't reduce the need for drug treatment, but may permit an increase in levodopa dosage by alleviating levodopa-induced dyskinesia. The risk (1%-3%) of serious or fatal complications is considered acceptable. J. R. Bruman (818) 789-3694 3527 Cody Road Sherman Oaks, CA 91403-5013