Richard Dubinsky

Practice parameter: Diagnosis of dementia (an evidence-based review) Report of the Quality Standards Subcommittee of the American Academy of Neurology

Objective: To update the 1994 practice parameter for the diagnosis of dementia in the elderly. Background: The AAN previously published a practice parameter on dementia in 1994. New research and clinical developments warrant an update of some aspects of diagnosis. Methods: Studies published in English from 1985 through 1999 were identified that addressed four questions: 1) Are the current criteria for the diagnosis of dementia reliable? 2) Are the current diagnostic criteria able to establish a diagnosis for the prevalent dementias in the elderly? 3) Do laboratory tests improve the accuracy of the clinical diagnosis of dementing illness? 4) What comorbidities should be evaluated in elderly patients undergoing an initial assessment for dementia? Recommendations: Based on evidence in the literature, the following recommendations are made. 1) The DSM-III-R definition of dementia is reliable and should be used (Guideline). 2) The National Institute of Neurologic, Communicative Disorders and Stroke–AD and Related Disorders Association (NINCDS-ADRDA) or the Diagnostic and Statistical Manual, 3rd edition, revised (DSM-IIIR) diagnostic criteria for AD and clinical criteria for Creutzfeldt–Jakob disease (CJD) have sufficient reliability and validity and should be used (Guideline). Diagnostic criteria for vascular dementia, dementia with Lewy bodies, and frontotemporal dementia may be of use in clinical practice (Option) but have imperfect reliability and validity. 3) Structural neuroimaging with either a noncontrast CT or MR scan in the initial evaluation of patients with dementia is appropriate. Because of insufficient data on validity, no other imaging procedure is recommended (Guideline). There are currently no genetic markers recommended for routine diagnostic purposes (Guideline). The CSF 14-3-3 protein is useful for confirming or rejecting the diagnosis of CJD (Guideline). 4) Screening for depression, B12 deficiency, and hypothyroidism should be performed (Guideline). Screening for syphilis in patients with dementia is not justified unless clinical suspicion for neurosyphilis is present (Guideline). Conclusions: Diagnostic criteria for dementia have improved since the 1994 practice parameter. Further research is needed to improve clinical definitions of dementia and its subtypes, as well as to determine the utility of various instruments of neuroimaging, biomarkers, and genetic testing in increasing diagnostic accuracy.

Practice parameter: Risk of driving and Alzheimer’s disease (an evidence-based review) Report of the Quality Standards Subcommittee of the American Academy of Neurology

Article abstract Studies of automobile accident frequency among drivers with AD have yielded conflicting results about the risk of accidents. To develop a practice parameter regarding driving and AD the authors performed a systematic review of the literature. The authors identified well-designed, controlled studies of driving and AD using the National Library of Medicine’s MEDLINE database. The authors also compared the relative rates of crashes and other performance measurements of driving ability in the populations studied. Driving was found to be mildly impaired in those drivers with probable AD at a severity of Clinical Dementia Rating (CDR) 0.5. This impairment was no greater than that tolerated in other segments of the driving population (e.g., drivers age 16 to 21 and those driving under the influence of alcohol at a blood alcohol concentration [BAC] < 0.08%). Drivers with AD at a severity of CDR 1 were found to pose a significant traffic safety problem both from crashes and from driving performance measurements.

Practice Parameter update: Evaluation and management of driving risk in dementia Report of the Quality Standards Subcommittee of the American Academy of Neurology

Objective: To review the evidence regarding the usefulness of patient demographic characteristics, driving history, and cognitive testing in predicting driving capability among patients with dementia and to determine the efficacy of driving risk reduction strategies. Methods: Systematic review of the literature using the American Academy of Neurologys evidence-based methods. Recommendations: For patients with dementia, consider the following characteristics useful for identifying patients at increased risk for unsafe driving: the Clinical Dementia Rating scale (Level A), a caregivers rating of a patients driving ability as marginal or unsafe (Level B), a history of crashes or traffic citations (Level C), reduced driving mileage or self-reported situational avoidance (Level C), Mini-Mental State Examination scores of 24 or less (Level C), and aggressive or impulsive personality characteristics (Level C). Consider the following characteristics not useful for identifying patients at increased risk for unsafe driving: a patients self-rating of safe driving ability (Level A) and lack of situational avoidance (Level C). There is insufficient evidence to support or refute the benefit of neuropsychological testing, after controlling for the presence and severity of dementia, or interventional strategies for drivers with dementia (Level U).

A randomized, double masked, controlled trial of botulinum toxin type A in essential hand tremor

Objective: To evaluate the safety and efficacy of botulinum toxin type A injection in essential tremor of the hand. Background: Botulinum toxin type A is an effective treatment for dystonia, spasticity, and other movement disorders and has been found to be useful in open-label studies and one double-masked study of essential hand tremor. Methods: One hundred thirty-three patients with essential tremor were randomized to low-dose (50 U) or high-dose (100 U) botulinum toxin type A (Botox) or vehicle placebo treatment. Injections were made into the wrist flexors and extensors. Patients were followed for 16 weeks. The effect of treatment was assessed by clinical rating scales, measures of motor tasks and functional disability, and global assessment of treatment. Hand strength was evaluated by clinical rating and by a dynamometer. Results: Both doses of botulinum toxin type A significantly reduced postural tremor on the clinical rating scales after 4 to 16 weeks. However, kinetic tremor was significantly reduced only at the 6-week examination. Measures of motor tasks and functional disability were not consistently improved with botulinum toxin type A treatment. Grip strength was reduced for the low- and high-dose botulinum toxin type A groups as compared with the placebo group. Adverse reactions consisted mainly of dose-dependent hand weakness. Conclusion: Botulinum toxin type A injections for essential tremor of the hands resulted in significant improvement of postural, but not kinetic, hand tremors and resulted in limited functional efficacy. Hand weakness is a dose-dependent significant side effect of treatment at the doses used in this study.

Driving in Alzheimer's disease

To determine if the impaired mental skills in Alzheimers Disease (AD) may adversely affect driving ability.

Patterns of cerebral glucose metabolism in patients with partial seizures

We analyzed local cerebral metabolic rates of glucose (LCMRglu) in 20 regions from 22 patients with complex partial seizures, who were taking neither phenytoin nor phenobarbital and who had normal CTs. Results were compared with data from 19 normal controls. Ten patients had left temporal, eight right temporal, and four bitemporal or generalized EEG discharges. There were no significant differences between patient and control values in any of 20 regions of interest. LCMRglu was depressed at the site of the epileptic focus: L/R ratio was 0.85 ± 0.12 (p < 0.003 compared with control), 0.92 ± 0.08 (p < 0.05), and 0.84 ± 0.1 (p < 0.001), respectively, in mesial, superior, and inferior temporal regions for patients with left temporal foci; 1.7 ± 0.96 (p < 0.04), 1.1 ± 0.1 (NS), and 1.15 ± 0.04 (p < 0.001) for patients with right temporal foci. Patients with left temporal EEG foci had significantly lower values than patients with right temporal foci in left superior frontal and thalamic as well as left temporal regions, while patients with right-sided EEG foci had depressed LCMRglu (compared with patients with left temporal EEG foci) restricted to right mesial temporal lobe. The patients with left temporal foci tended to have longer seizure histories (22.7 ± 5.4 versus 11 ± 5.6 years; p < 0.001). There was an inverse correlation between length of seizure history and mean LCMRglu (r = 0.38; 0.1 > p > 0.05). Our study suggests that LCMRglu is not depressed in regions beyond the epileptic focus when patients are not taking drugs known to decrease cerebral glucose metabolism.

Progressive supranuclear palsy and a multi‐infarct state

In 58 patients with progressive supranuclear palsy (PSP), 19 (32.8%) had CT, MRI, or autopsy evidence of a multi-infarct (MI) state. The clinical findings in the infarct syndrome were similar to idiopathic PSP. Five MI-PSP patients had had a stroke, four had focal dystonia, two had hemiparesis, and one had an intention tremor of recent onset. In contrast, only 5.9% (12.9% of those with CT or MRI) of 426 Parkinsons disease patients had evidence of strokes. One case of PSP studied pathologically was attributed to cerebral amyloid angiopathy.

Assessment: Efficacy of transcutaneous electric nerve stimulation in the treatment of pain in neurologic disorders (an evidence-based review) Report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology

Objective: To determine if transcutaneous electric nerve stimulation (TENS) is efficacious in the treatment of pain in neurologic disorders. Methods: We performed a systematic literature search of Medline and the Cochrane Library from inception to April 2009. Results: There are conflicting reports of TENS compared to sham TENS in the treatment of chronic low back pain, with 2 Class II studies showing benefit, but 2 Class I studies and another Class II study not showing benefit. Because the Class I studies are stronger evidence, TENS is established as ineffective for the treatment of chronic low back pain (2 Class I studies). TENS is probably effective in treating painful diabetic neuropathy (2 Class II studies). Recommendations: Transcutaneous electric nerve stimulation (TENS) is not recommended for the treatment of chronic low back pain (Level A). TENS should be considered in the treatment of painful diabetic neuropathy (Level B). Further research into the mechanism of action of TENS is needed, as well as more rigorous studies for determination of efficacy.

Randomized double-blind study of botulinum toxin type B for sialorrhea in ALS patients

Twenty ALS patients with sialorrhea refractory to medical therapy were enrolled in this double‐blind, randomized study to receive either 2,500 U of botulinum toxin type B (BTxb) or placebo into the bilateral parotid and submandibular glands using electromyographic guidance. Patients who received BTxb reported a global impression of improvement of 82% at 2 weeks compared to 38% of those who received placebo (P < 0.05). This significant effect was sustained at 4 weeks. At 12 weeks, 50% of patients who received BTxb continued to report improvement compared to 14% of those who received placebo. There were no significant adverse events, including dysphagia, in the BTxb group, and there was no significant increase in the rate of decline of vital capacity. Muscle Nerve 39: 137–143, 2009

Botulinum toxin treatment of essential head tremor

Article abstract-We examined in a double-blind, placebo-controlled study the effects of botulinum toxin in 10 patients with essential head tremor. Each subject received two treatments approximately 3 months apart, one with botulinum toxin injections and another with normal saline injections into the sternocleidomastoid and splenius capitis muscles. The subjects were assessed before each treatment and at 2, 4, and 8 weeks after injections. There was moderate to marked improvement in clinical ratings in five subjects after botulinum toxin injections and in one subject after placebo. There was moderate to marked subjective improvement in five patients with botulinum toxin as compared with three subjects with placebo. Side effects were mild and transient. We conclude that botulinum toxin may be useful for patients with essential head tremor who have failed to benefit from oral medications. NEUROLOGY 1995;45: 822-824