New and Noteworthy Information—June 2017
Can Biomarkers Predict Cognitive Deficits in Parkinson’s Disease?
Biomarkers may predict which patients with Parkinson’s disease will have significant cognitive deficits within the first three years after diagnosis, according to a study published May 17 in PLOS One. Researchers conducted an international, prospective study of 423 newly diagnosed and untreated patients with Parkinson’s disease with no signs of cognitive impairment at the time of enrollment in 2010. Investigators conducted brain scans, genetic tests, and analyses of CSF at baseline and during follow-up. At three years, between 15% and 38% of participants had developed cognitive impairment. Brain scans identified dopamine deficiency and decreased brain volume as predictors of cognitive decline. Low CSF beta-amyloid level and single-nucleotide polymorphisms (SNPs) in COMT and BDNF also predicted cognitive decline. These SNPs previously had been associated with cognitive impairment.
Caspell-Garcia C, Simuni T, Tosun-Turgut D, et al. Multiple modality biomarker prediction of cognitive impairment in prospectively followed de novo Parkinson disease. PLoS One. 2017 May 17;12(5):e0175674.
Service Members With Concussive Blast TBI Have Worsening Outcomes
Military service members with concussive blast traumatic brain injury (TBI) have considerable decline in clinical outcomes over five years, according to a study published online ahead of print May 1 in JAMA Neurology. This prospective longitudinal study enrolled active-duty US military after concussive blast injury in the acute to subacute stage and combat-deployed control individuals in Afghanistan or after medical evacuation to Germany from November 1, 2008, through July 1, 2013. Physicians in the United States performed one- and five-year clinical evaluations. Among the 94 participants, global disability, satisfaction with life, neurobehavioral symptom severity, psychiatric symptom severity, and sleep impairment were significantly worse in patients with concussive blast TBI, compared with combat-deployed controls, whereas performance on cognitive measures was no different between groups at the five-year evaluation.
Mac Donald CL, Barber J, Jordan M, et al. Early clinical predictors of 5-year outcome after concussive blast traumatic brain injury. JAMA Neurol. 2017 May 1 [Epub ahead of print].
Biomarker Linked to Increased Risk of Ischemic Stroke in Women
High levels of β2-microglobulin are associated with an increased risk of ischemic stroke among women, according to a study published online ahead of print May 10 in Neurology. Researchers performed a nested case–control study among women enrolled in the Nurses’ Health Study who provided blood samples between 1989 and 1990 and were free of prior stroke and cancer. Investigators measured β2-microglobulin levels in 473 ischemic stroke cases and 473 controls matched on age, race, and other variables. Median levels of β2-microglobulin were 1.86 mg/L in cases and 1.80 mg/L in controls. Women in the highest β2-microglobulin quartile had a multivariable-adjusted increased risk of ischemic stroke, compared with women in the lowest quartile (odds ratio, 1.56). Results were similar when restricted to those without chronic kidney disease.
Rist PM, Jiménez MC, Rexrode KM. Prospective association between β2-microglobulin levels and ischemic stroke risk among women. Neurology. 2017 May 10 [Epub ahead of print].
Female Hormones May Cause Headache in Girls With Migraine
Age and pubertal development could moderate the effect of ovarian hormones on days of headache onset in girls with migraine, according to a study published online ahead of print May 8 in Cephalalgia. The study included 34 girls with migraine grouped into three age strata (ie, prepubertal, pubertal, and postpubertal). Participants collected daily urine samples and recorded the occurrence and severity of headache in a daily diary. Urine samples were assayed for estrone glucuronide and pregnandiol glucuronide, and the daily change in each was calculated. The primary outcome measures were headache onset days and headache severity. Models of headache onset days demonstrated a significant interaction between age and pregnandiol glucuronide. Change in pregnandiol glucuronide was associated with headache severity.
Martin VT, Allen JR, Houle TT, et al. Ovarian hormones, age and pubertal development and their association with days of headache onset in girls with migraine: an observational cohort study. Cephalalgia. 2017 Jan 1 [Epub ahead of print].
PTSD Is Associated With Risk for Dementia Diagnosis
Posttraumatic stress disorder (PTSD) diagnosis is associated with an increased risk for dementia diagnosis that varies with psychotropic medication, according to a study published in the May issue of the Journal of the American Geriatrics Society. Researchers examined information from 417,172 veterans age 56 and older without dementia or mild cognitive impairment. During the study’s nine-year follow-up period, participants had a clinical encounter every two years. PTSD diagnosis significantly increased the risk for dementia diagnosis. The hazard ratio for dementia diagnosis among veterans diagnosed with PTSD who did not use psychotropic medications was 1.55. Among veterans diagnosed with PTSD and prescribed psychotropic medication, the hazard ratio for dementia diagnosis ranged from 1.99 for SSRIs to 4.21 for atypical antipsychotics.
