New and Noteworthy Information—June 2016
Aspects of spatial navigation may be particularly sensitive for detecting the earliest cognitive deficits of Alzheimer’s disease, according to a study published April 26 in the Journal of Alzheimer’s Disease. This study included 42 clinically normal people without preclinical Alzheimer’s disease, 13 clinically normal people with preclinical Alzheimer’s disease, and 16 people with early-stage symptomatic Alzheimer’s disease. Preclinical Alzheimer’s disease was defined based on CSF Aβ42 levels below 500 pg/mL. Preclinical Alzheimer’s disease was associated with deficits in the use of a wayfinding strategy, but not in the use of a route-learning strategy. In addition, post hoc analyses indicated that wayfinding performance had moderate sensitivity and specificity. Results also confirmed early-stage symptomatic Alzheimer’s disease-related deficits in the use of wayfinding and route-learning strategies.
One meal per week of seafood and long-chain omega-3 fatty acids protects against decline in multiple cognitive domains, according to a study published online ahead of print May 4 in Neurology. Researchers examined 915 participants who completed at least one follow-up cognitive assessment and provided dietary data. Scores for global cognitive function and five cognitive domains were assessed using 19 cognitive tests. Consumption of seafood was associated with slower decline in semantic memory and perceptual speed in separate models adjusted for age, sex, education, participation in cognitive activities, physical activity, alcohol consumption, smoking, and total energy intake. In secondary analyses, APOE ε4 carriers demonstrated slower rates of decline in global cognition and in multiple cognitive domains with weekly seafood consumption and with moderate to high long-chain omega-3 intake from food.
Persistent environmental pollutants measured in blood are significantly associated with amyotrophic lateral sclerosis (ALS) and may represent modifiable risk factors, according to a study published online ahead of print May 9 in JAMA Neurology. Participants included 156 cases and 128 controls. Complete demographic and pollutant data were available for 101 cases and 110 controls. Survey data revealed that reported pesticide exposure in the cumulative exposure windows was significantly associated with ALS. A multivariable model of measured persistent environmental pollutants in the blood, representing cumulative occupational and residential exposure, showed increased odds of ALS for two organochlorine pesticides, two polychlorinated biphenyls, and one brominated flame retardant. There was modest concordance between survey data and the measurements of persistent environmental pollutants in blood. Additionally, tau correlation coefficients ranged from –0.18 to 0.24.
Outcomes of sports-related concussion vary according to the level of competition, according to a study published online ahead of print May 2 in JAMA Pediatrics. Three injury surveillance programs recorded 1,429 sports-related concussions between 2012 and 2014 among youth, high school, and college-level football athletes. Across all levels, 15.3% of concussions resulted in return to play at least 30 days after the concussion, and 3.1% resulted in return to play less than 24 hours after the concussion. Compared with youth, a higher number of concussion symptoms were reported in high school athletes. Compared with college athletes, the odds of return to play at least 30 days after injury were larger in youth athletes and high school athletes.
A screening test for newborns identifies infants with Niemann-Pick type C, according to a study published May 4 in Science Translational Medicine. The bile acids most elevated in infants with Niemann-Pick type C were identified as 3β,5α,6β-trihydroxycholanic acid and its glycine conjugate, which were shown to be metabolites of cholestane-3β,5α,6β-triol. Analysis of dried blood spots from 4,992 controls, 134 Niemann-Pick type C carriers, and 44 subjects with Niemann-Pick type C provided 100% sensitivity and specificity in the study samples. The researchers found that infants with Niemann-Pick type C have about thirtyfold higher amounts of 3β,5α,6β-trihydroxycholanic acid in the blood than healthy individuals. In addition, levels of 3β,5α,6β-trihydroxycholanic acid also could distinguish between patients with Niemann-Pick type C and carriers of the disease who show no symptoms.
The FDA has approved pimavanserin for the treatment of hallucinations and delusions associated with Parkinson’s disease psychosis. The approval is based on data from a phase III study and other supportive studies. In the phase III study, pimavanserin significantly reduced the frequency and severity of psychotic symptoms, compared with placebo, on the Scale for Assessment of Positive Symptoms—Parkinson’s Disease. This benefit was achieved without impairing motor function. The most common adverse reactions in this study were peripheral edema and confusional state. The drug has a boxed warning alerting health care professionals about an increased risk of death associated with the use of atypical antipsychotics to treat older people with dementia-related psychosis. Acadia Pharmaceuticals, headquartered in San Diego, markets the product under the name Nuplazid.