New and Noteworthy Information—September 2016
Patients with anemia have increased mortality after stroke, according to a study published online ahead of print August 17 in the Journal of the American Heart Association. Researchers analyzed data from a cohort of 8,013 patients with stroke who were consecutively admitted over 11 years. Anemia was present in 24.5% of the cohort on admission and was associated with increased odds of mortality at most of the time points examined up to one year following stroke. Elevated hemoglobin also was associated with increased mortality. In addition, investigators conducted a systematic review using various databases. When combined with the cohort from the current study, the pooled population had 29,943 patients with stroke. Anemia on admission was associated with an increased risk of mortality in ischemic stroke and hemorrhagic stroke.
Bedside EEG methods may indicate the level of awareness of patients in a vegetative state, according to a study published online ahead of print August 4 in Annals of Neurology. Fourteen patients with severe brain injuries were evaluated with an EEG vibrotactile attention task designed to identify a hierarchy of residual somatosensory and cognitive abilities. Each patient also was assessed with a clinical behavioral scale and two fMRI assessments of covert command following. Six patients produced only sensory responses, with no evidence of cognitive event-related potentials. Furthermore, eight patients demonstrated reliable bottom-up attention-orienting responses. No patient showed evidence of top-down attention. Only patients who followed commands, whether overtly with behavior or covertly with functional neuroimaging, also demonstrated event-related potential evidence of attentional orienting.
The PET tracer [18F]-AV-1451 may help identify the stages of the preclinical and clinical phases of Alzheimer's disease, according to a study published online ahead of print July 25 in JAMA Neurology. In all, 59 participants (64% male; mean age, 74) underwent PET imaging. The [18F]-AV-1451 standardized uptake value ratio (SUVR) in the hippocampus and Alzheimer's disease cortical signature regions distinguished participants with Alzheimer's disease from cognitively normal participants. A SUVR cutoff value of 1.19 from Alzheimer's disease cortical signature regions best distinguished these groups. Amyloid β-positivity was associated with an elevated [18F]-AV-1451 SUVR in Alzheimer's disease cortical signature regions, but not in the hippocampus. Amyloid β-positivity alone was not related to hippocampal volume or Alzheimer's disease signature cortical thickness. An elevated [18F]-AV-1451 SUVR was associated with brain volumetric loss.
Symptom exacerbations after concussion are common among children and may not impede recovery, according to a study published online ahead of print August 1 in JAMA Pediatrics. Eligible participants were between ages 11 and 18 and had sustained a concussion that did not result in an abnormal CT scan or require hospital admission. The mean age of the 63 participants (34.9% girls) was 13.8. Symptom spikes occurred in 31.7% of the sample. An abrupt increase in mental activity from one day to the next increased the risk of a symptom spike. Patients with symptom spikes were initially more symptomatic in the emergency department and throughout the observation period, but did not differ from the group without symptom spikes on cognition or balance 10 days following injury.
The FDA has approved the supplemental Biologics License Application from Ipsen Biopharmaceuticals for Dysport (abobotulinumtoxinA) for injection in the treatment of lower limb spasticity in pediatric patients age 2 and older. This approval is based on a phase III pivotal study of 235 pediatric patients ages 2 to 17 with lower limb spasticity because of cerebral palsy causing dynamic equinus foot deformity. Patients treated with Dysport showed statistically significant improvement in ankle plantar flexor muscle tone. Like all botulinum toxin products, Dysport has a boxed warning stating that the effects of the botulinum toxin may spread from the area of injection to other areas of the body, causing symptoms similar to those of botulism. Ipsen Biopharmaceuticals is headquartered in Basking Ridge, New Jersey.
Lower BMI in late life is associated with greater cortical amyloid burden, according to a study published June 18 in the Journal of Alzheimer's Disease. The study entailed cross-sectional analyses that were completed using baseline data from the Harvard Aging Brain Study, which included 280 cognitively normal adults ages 62 to 90. Assessments included medical histories and physical exams, Pittsburgh compound B (PiB) PET amyloid imaging, and APOE4 genotyping. In the primary analysis, greater PiB retention was associated with lower BMI. In the secondary analyses, APOE4 carrier status and normal BMI, as opposed to overweight or obese BMI, were associated with greater PiB retention. The interaction between BMI and APOE4 also was significant. Future studies should seek to clarify the mechanism of this association, said the researchers.
