Chinese people may have a higher risk of stroke than Caucasians, according to research published in the July 16 Neurology. Investigators analyzed studies conducted since 1990 in Chinese populations of first-ever stroke incidence and pathologic types and subtypes of stroke. The team examined hospital- and community-based studies. They also examined community-based stroke studies in Caucasian populations. Age-standardized, annual, first-ever stroke incidence in community-based studies was higher among Chinese than among Caucasian populations. Intracerebral hemorrhage accounted for a larger, more variable proportion of strokes in China than in Taiwan, in Chinese community-based than in hospital-based studies, and in community-based Chinese than in Caucasian studies. The overall proportion of lacunar ischemic stroke was higher in Chinese than in Caucasian populations, but variable study methodologies precluded reliable comparisons.
Narcolepsy in humans may be triggered partly by a proliferation of cells containing histamine, according to data published online ahead of print July 2 in Annals of Neurology. Investigators used immunohistochemistry for histidine decarboxylase (HDC) and quantitative microscopy to detect histamine cells in patients with narcolepsy, Hcrt receptor-2 mutant dogs, and three mouse narcolepsy models. The researchers found an average 64% increase in the number of histamine neurons in human narcolepsy with cataplexy, with no overlap between patients with narcolepsy and controls. The investigators did not observe altered numbers of HDC cells in any of the animal models of narcolepsy, however. The increased histamine cell numbers observed in human narcolepsy may be related to the process causing the human disorder, said the study authors.
Epilepsy may be associated with an early onset of cognitive decline, according to data published online ahead of print on July 8 in JAMA Neurology. Investigators conducted a retrospective observational study of patients at a memory and aging center from 2007 to 2012. Twelve participants had amnestic mild cognitive impairment (aMCI) plus epilepsy, 35 had Alzheimer’s disease plus epilepsy, and seven had Alzheimer’s disease plus subclinical epileptiform activity. Patients with aMCI and epilepsy presented with symptoms of cognitive decline 6.8 years earlier than patients with aMCI who did not have epilepsy. Patients with Alzheimer’s disease who had epilepsy presented with cognitive decline 5.5 years earlier than patients with Alzheimer’s disease who did not have epilepsy. Patients with Alzheimer’s disease and subclinical epileptiform activity also had an early onset of cognitive decline.
Globus pallidus interna (GPi) deep brain stimulation (DBS) may be an effective therapy for DYT1-associated torsion dystonia, according to a study published in the July issue of Neurosurgery. Researchers conducted a retrospective chart review of 47 consecutive patients with DYT1 who were treated by a single surgical team during a 10-year period and followed for up to 96 months. Symptom severity was quantified with the Burke–Fahn–Marsden Dystonia Rating Scale. Motor symptom severity was reduced to less than 20% of baseline after two years of DBS therapy. Disability scores were reduced to less than 30% of baseline. Symptomatic improvement was sustained throughout follow-up. Sixty-one percent of patients had discontinued all dystonia-related medications at their last follow-up. Ninety-one percent had discontinued at least one class of medication.
Concurrent cerebrovascular disease is a common neuropathologic finding in older individuals with dementia, according to an article published online ahead of print July 10 in Brain. Cerebrovascular disease, vascular pathology, and vascular risk factors were studied in 5,715 cases from the National Alzheimer’s Coordinating Centre database who had a single neurodegenerative disease diagnosis based on a neuropathologic examination with or without cerebrovascular disease. After controlling for age and gender, the researchers found a lower prevalence of coincident cerebrovascular disease among patients with α-synucleinopathies, frontotemporal lobar degeneration due to tau and TAR DNA-binding protein 43, and prion disease than among patients with Alzheimer’s disease. This result was more significant in younger patients. Data suggest that these disorders should be targeted by treatments for cerebrovascular disease, according to the researchers.
Athletes who do not get enough sleep the night before undergoing baseline concussion testing may not perform as well as they expect, according to research presented at the 2013 Annual Meeting of the American Orthopaedic Society for Sports Medicine in Chicago. Researchers reviewed 3,686 nonconcussed athletes (1,315 female) with baseline symptom and ImPACT neurocognitive scores. Individuals reported their previous night’s sleep duration as fewer than seven hours, seven to nine hours, or more than nine hours. The study authors observed significant differences in reaction time, verbal memory, and visual memory in the group that had slept less than seven hours. Visual-motor speed scores did not seem to be affected. Significant differences in the total number of reported symptoms were associated with sleeping fewer than seven hours.