Mildly elevated serum uric acid was associated with an increased burden of cerebral ischemic pathology among 177 community-dwelling adults ages 20 to 92, reported researchers in the October 2 Neurology. As detected on proton density and T2-weighted brain MRI, participants with high-normal serum uric acid were more likely to be in the highest quartile of total volume of white matter hyperintensities (WMH; odds ratio [OR], 2.6), periventricular WMH volume (OR, 2.5), and subcortical WMH volume (OR, 2.8). “High normal uric acid increased the odds of having excessive ischemic burden four- to fivefold in adults ages 60 and older,” added the authors. They concluded that a clinical trial of antihyperuricemic medication for the treatment or prevention of chronic brain ischemia might be warranted.

Nicotine or selective nicotine agonists may be a useful treatment strategy to reduce levodopa-induced dyskinesias, according to a study in the October 24 online Annals of Neurology. Levodopa-naïve monkeys were pretreated with nicotine administered via their drinking water and then given 5 mg/kg of levodopa twice daily. The investigators reported “a decrease in total dyskinesias of about 50%” during the eight-week study period. In a crossover phase, levodopa-treated monkeys originally receiving untreated water were administered nicotine. “Nicotine treatment to levodopa-primed monkeys led to an approximately 35% reduction in total dyskinesias,” stated the authors. They also noted that nicotine treatment did not appear to affect the antiparkinsonian action of the levodopa. In addition, animals already receiving nicotine were switched to untreated water, which led to a significant increase in levodopa-induced dyskinesias.

Disease progression and disability accumulation in patients with multiple sclerosis (MS) are not influenced by cigarette smoking, according to the results of a study in the October 9 Neurology. Analysis focused on 263 patients who were in the initial and secondary stages of MS and who were smokers. Smoking status was not associated with the development or age at onset of secondary progression, age at onset of progression in patients with primary progressive MS, or with the time from disease onset to Expanded Disability Status Scale (EDSS) scores of 4.0 and 6.0. The investigators also reported no correlation between pack-years smoked and EDSS scores and the rate of progression as measured with the Multiple Sclerosis Severity Score. These findings are in contrast with a prior investigation, but the authors asserted that their study included more participants and personal interviews, which leads them to believe that the results of the present study are more accurate.

Valsartan appeared to protect against b-amyloid–mediated cognitive deterioration in a mouse model of Alzheimer’s disease, at a dose about twofold lower than that typically used to treat hypertension in humans. As reported in the October 25 online Journal of Clinical Investigation, valsartan was the only drug among 55 antihypertensive medications examined that significantly reduced Alzheimer’s disease–type beta-amyloid protein accumulation and attenuated oligomerization of beta-amyloid peptides into high-molecular-weight oligomeric peptides in vitro. In addition, mice given preventive treatment with valsartan had significantly reduced Alzheimer’s disease–type neuropathology and lower levels of soluble high-molecular-weight extracellular oligomeric b-amyloid peptides in the brain. The investigators suggested that certain antihypertensives may protect against progressive beta-amyloid–related memory deficits in patients with Alzheimer’s disease or in those at high risk for the disease.

The FDA has expanded use of the bacterial meningitis vaccine Menactra®, manufactured by Sanofi Pasteur Inc, to include recipients ages 2 to 10. The vaccine’s original approval in 2005 only included recipients ages 11 to 55. Effectiveness was measured in eight clinical studies that included 10,057 participants who received Menactra and 5,266 who received Menomune®, the only other meningococcal vaccine available in the US for use in children. An immune response was observed one month after vaccination, and the most common adverse events reported were pain at the injection site and irritability, followed by diarrhea, drowsiness, and lack of appetite. Guillain-Barré syndrome was noted as a possible but unproven risk in some adolescents following immunization with Menactra, at an estimated rate of one per one million recipients; those who have been previously diagnosed with Guillain-Barré syndrome should not receive the vaccine, recommended the FDA.

hort-term cognitive improvement in patients with encephalopathy following treatment for Lyme disease may be achieved with the use of IV antibiotic treatment, reported researchers in a study published in the October 10 online issue of Neurology. Thirty-seven patients who tested positive for Lyme disease, received at least three weeks of IV antibiotic treatment, and showed objective memory impairment were randomized to receive 10 weeks of IV ceftriaxone or placebo; 20 healthy controls were also enrolled for a measure of practice effect. At week 12, investigators observed a significant treatment-by-time interaction across six cognitive domains that favored the antibiotic-treated group. “The improvement was generalized and moderate in magnitude, but it was not sustained to week 24,” noted the authors. Fatigue, pain, and impaired physical functioning were also improved with antibiotics at week 12, and the effect was sustained for pain and physical functioning at week 24. Adverse effects occurred in 26.1% and 7.1% of antibiotic-treated and placebo patients, respectively, and resolved without permanent injury.

Researchers found no causal association between early exposure to mercury from thi-merosol-containing vaccines and neuropsychologic performance at ages 7 to 10 in a review of immunization records of 1,047 children. As reported in the September 27 New England Journal of Medicine, among the 42 outcomes assessed, the associations were few and “were small and almost equally divided between positive and negative effects,” stated the authors. Higher prenatal mercury exposure was associated with improvement on a single measure of language performance but poorer attention and executive functioning, while exposure from birth to 28 days resulted in reduced speech articulation test results but improved fine motor control. Attention and executive functioning, in addition to fine motor control, also appeared to be improved with increasing levels of mercury exposure from birth to 7 months.

As reported in the October Archives of Neurology, risk of cognitive impairment or dementia was increased in 1,019 first-degree relatives of 162 patients with Parkinson’s disease as compared with 858 relatives of 147 matched controls (hazard ratio [HR], 1.37). The authors of the study also noted that the risk was “particularly increased in relatives of patients with onset of Parkinson’s disease at age 66 years or younger (youngest tertile; HR, 1.73).” Additional analysis of 2,716 first-degree relatives of 411 patients with Parkinson’s disease referred to the Mayo Clinic in Rochester, Minnesota, also indicated an increased risk of dementia or cognitive impairment with younger age at onset of the relative’s disease, although the risk did not vary by other clinical characteristics. The researchers suggested that cognitive impairment or dementia may share familial susceptibility factors with Parkinson’s disease.

Highly active antiretroviral treatment (HAART) appeared to halt neurodegenerative processes caused by HIV-1, according to the results of a study published in the October 9 Neurology. Archived CSF samples taken from 53 patients before initiation of HAART showed increased pretreatment CSF neurofilament protein in 21 subjects (median level, 780 ng/L; intraquartile range, 480 to 7,300 ng/L). After three months of HAART, the median level was significantly lower (340 ng/L), and the neurofilament protein concentrations were normal in 10 patients whose levels had been elevated at baseline; only four patients still had elevated levels after one year of HAART. “These effects on CSF neurofilament protein were seen in association with clinical improvement in AIDS dementia complex patients, decreases in plasma and CSF HIV-1 RNA and CSF neopterin, and increases in blood CD4 T cell counts,” noted the authors.          

NR