Severe depression might eventually be added to the indications for vagus nerve stimulation, suggest preliminary findings published online in Biological Psychiatry. After eight weeks, about 40% of 30 patients with major depression or bipolar disorder showed a treatment response on clinical and depression rating scales. A larger multicenter trial is set to begin next year.

A review of 22 controlled trials of acupuncture for the treatment of recurrent headache revealed a trend in favor of acupuncture over placebo, according to a meta-analysis published in the November issue of Cephalalgia. Since most of the studies were small and had methodologic flaws, however, the authors withheld any recommendations for clinical practice. Acupuncture seems to be beneficial, they concluded, but it is still unclear which treatment strategies (for example, specific acupoints, type of stimulation, frequency) are most promising for defined groups of headache patients.

Folic acid may be more critical than vitamin B12 to memory function in very old age, Swedish researchers said. They assessed the ability of healthy, very old adults (ages 90 to 101) to perform episodic recall and recognition tasks. Neither levels of serum vitamin B12 nor interactive levels of B12 and folic acid affected episodic memory. According to the report in Biological Psychiatry, low levels of folic acid were, however, associated with poorer performance in object recall and word recall. Secondary memory, but not primary memory, reflected the effects of low folic acid.

Electrodiagnostic testing for carpal tunnel syndrome should control for relevant covariates, according to a University of Michigan study. Reported in Muscle & Nerve, the study was designed to improve diagnostic accuracy by determining normative values for nerve conduction tests. Median and ulnar sensory amplitude and latency were evaluated in a cohort of 326 workers. The findings, said the researchers, "illustrate the importance of considering covariates such as age, sex, hand temperature, and anthropometric factors."

Corticotropin-releasing factor immunoreactivity (CRF-IR) may be a marker of early dementia and Alzheimer's disease, according to a report in the November Archives of General Psychiatry. Researchers from Mount Sinai School of Medicine, New York, analyzed postmortem CRF-IR and somatostatin-like immunoreactivity (SLI) levels in the cortices of 66 elderly nursing home residents. Subjects without dementia or with possible, mild, or moderate dementia were compared to those diagnosed with severe dementia. Although levels of SLI and CRF-IR were significantly reduced in severe dementia, only CRF-IR was lower in mild dementia.

Levetiracetam (Keppra(tm)) has been approved by the Food and Drug Administration as adjunctive therapy for partial onset seizures in adults. Efficacy was established in three multicenter, randomized, double-blind, placebo-controlled trials. In all three, patients treated with 1,000 mg/d, 2,000 mg/d, or 3,000 mg/d had a significantly greater reduction in weekly seizure frequency than patients taking placebo. Tablets in three dosage strengths (250 mg, 500 mg, and 750 mg) are expected to be available from UCB Pharma in the spring.

Stent placement led to complete, long-term resolution of carotid artery dissection in seven patients, according to a prospective study in December's Neurosurgery. Six patients had no radiologic evidence of restenosis, while an additional asymptomatic vessel occlusion developed in one. All patients remained clinically stable and had no ischemic symptoms during the mean 3.5-year posttreatment period.

The site of deep brain stimulation may subtly influence treatment responses in Parkinson's disease, according to a randomized, blinded study in December's Neurosurgery. Both pallidal and subthalamic nucleus (STN) stimulation led to improved motor scores in 10 patients. In conjunction with levodopa, however, pallidal stimulation provided greater axial symptom relief. Drug-induced dyskinesias were diminished by stimulation at either site, although levodopa dosage requirements dropped only in the STN group.

Formation of Borrelia burgdorferi immune complexes is apparently common in patients with active Lyme disease, according to report in the November 24 JAMA. The majority (96%) of serum samples taken from 156 patients meeting established criteria for Lyme disease had detectable immune complexes. No recovered patients and two of 147 control subjects were positive. "The B burgdorferi assay appears to allow early diagnosis of infection before conventional antibody tests become positive," the authors concluded.

Refinement of stereotactic radiosurgery can help preserve hearing in patients treated for vestibular schwannomas, according to a study in the December issue of Neurosurgery. Fractionation of therapeutic radiation controlled tumor growth in most (97%) of 31 patients, and also reduced incidental damage to the cochlear nerve. Overall, useful hearing (Gardner-Robertson Class 1-2) was maintained in 77% of the patients at two years after treatment.

Hypertension is a risk factor for cognitive decline, according to a longitudinal, population-based study published in the December 10 Neurology. Blood pressure and mental status were recorded for 1,373 subjects (ages 59 to 71) living in western France over a period of four years. Cognitive decline—a drop of four or more points on the Mini-Mental State Examination—was more likely among subjects with hypertension (defined as systolic blood pressure greater than or equal to 160 mm Hg or diastolic blood pressure greater than or equal to 95 mm Hg). The risk was highest with untreated chronic hypertension, while treatment lowered the risk considerably.

Neuronal degeneration in age-related maculopathy and in Alzheimer's disease may "have a common pathogenesis," according to a report in the November 1 issue of the American Journal of Epidemiology. Smoking and atherosclerosis are risk factors for both conditions; however, it is "unlikely that the apolipoprotein E genotype contributes" to the link, the researchers said. They reached their conclusions after studying the comorbidity of the two conditions in a subset of 1,438 subjects at least age 75 years old from the population-based Rotterdam Study in the Netherlands.

The new variant Creutzfeldt-Jakob disease (CJD) is caused by the same strain of prions that causes bovine spongiform encephalopathy (BSE), according to a study from the University of California at San Francisco. Stanley Prusiner, MD, and Stephen DeArmond, MD, created a line of transgenic mice engineered to contain genes for the bovine prion protein. Inoculated prions from cows with BSE and human cases of new variant CJD produced identical patterns of disease in these Tg(BOPrP) mice, according to the report in the December 20 issue of the Proceedings of the National Academy of Sciences. "These findings argue unequivocally that BSE and new variant CJD are [derived from] the same strain of prion," said Dr. DeArmond.

Pending a final decision by the Food and Drug Administration on the New Drug Application for Myotrophin(r) (mecasermin), Cephalon has discontinued the Myotrophin Expanded Access (Treatment IND) Program. The three-year program had provided free access to Myotrophin for hundreds of patients with amyotrophic lateral sclerosis. According to Cephalon, there are no current plans to manufacture additional quantities of the drug or to initiate further studies of its safety and efficacy. Although final shipments to Treatment IND patients were scheduled for the end of December 1999, Cephalon applied for a waiver to expand the amounts to a several-months' supply.

Given three to five hours after stroke onset, intravenous recombinant tissue-type plasminogen activator (rt-PA) does not improve outcome at 90 days, according to a report in the December 1 JAMA. The phase 3, placebo-controlled, double-blind, randomized Alteplase ThromboLysis for Acute Noninterventional Therapy in Ischemic Stroke (ATLANTIS) study was conducted between December 1993 and July 1998. Excellent recovery at 90-day follow-up was reported in 32% of the placebo group and 34% of the rt-PA group, and there were no differences in secondary outcome measures. In the rt-PA group, however, rates of symptomatic intracerebral hemorrhage were higher during the first 10 days, and mortality was slightly higher at 90 days. Most of the patients (80%) were enrolled between four and five hours after onset of symptoms, and strokes tended to be milder than in the NINDS trials.

The first sequencing of a complete (euchromatic portion of a) human chromosome was reported in the December 2 issue of Nature. The researchers chose to map chromosome 22, the second smallest of the human autosomes, not only because it is the source of numerous congenital anomalies, but also because it "would provide an excellent opportunity to show the feasibility of completing the sequence of a substantial unit of the human genome." The multicenter team members, who have made the emerging results of their study available on internet sites and public databases, plan to "continue to pursue this data release policy as we move closer to the anticipated completed sequence of humans, mice and other complex genomes."

The inferior parietal lobule is 6% larger in men than in women, reported Johns Hopkins researchers. That region of the brain is associated with the interpretation of spatial relationships, the examination of mathematical problems, and the perception of time and speed. Psychiatrist and researcher Godfrey Pearlson, MD, added that Albert Einstein's brain and the brains of other physicists and mathematicians have been found to have large inferior parietal lobules in postmortem studies. Dr. Pearlson stressed, however, that the size of the inferior parietal lobule does not mean that "men are automatically better at some things than women." The slight association between sex and the size of that particular brain structure is apparent only when assessing large populations, he added.

An experimental vaccine may have the potential to promote spinal cord nerve regeneration, according to a report in the November issue of Neuron. Researchers from McGill University and the University of Montreal reported that the new vaccine stimulates the immune system to generate antibodies against proteins produced by myelin that inhibit the regeneration of nerves. "This vaccine approach allowed us to target many types of inhibitors, not just one as has been the case in the past," according to researcher Lisa McKerracher, MD.

Aggrenox(r) (aspirin/extended-release dipyridamole) has been approved by the Food and Drug Administration for stroke prevention in patients with a prior stroke or transient ischemic attack. The approval of Boehringer Ingelheim's antiplatelet combination was based on results of the second European Stroke Prevention Study, the largest trial to date focusing on preventing recurrent stroke.

On SPECT imaging, dopamine transporter density was about 70% greater in adult attention-deficit/hyperactivity disorder (ADHD) than in healthy controls, researchers reported in the December 18/25 Lancet. Noting that the dopamine transporter is "a major target of the majority of drugs used to treat ADHD," the researchers suggested that further SPECT studies might be used to individualize pharmacotherapy, evaluate new medications, and clarify the mechanisms of ADHD and its treatment.

The "annual stroke burden is far greater than the often-quoted figure of half a million first-ever or recurrent strokes," according to an estimate proposed by researchers in the December issue of Stroke. The new estimate of 750,000 strokes in the United States during 1995 was based on "a large administrative claims database." Most prior studies, the researchers noted, "used relatively small and homogeneous population-based stroke registries." Administrative databases, they said, "are becoming increasingly more important sources of information for epidemiological studies."

—Kathryn Blair
-Shauna Kubose

Return to table of contents