Device May Predict Seizure Risk
The NeuroPace RNS System may enable clinicians to identify when patients are at highest risk for seizures, thus allowing patients to plan around these events, according to a study published January 8 in Nature Communications. In 37 subjects with the implanted brain stimulation device, which detected interictal epileptiform activity (IEA) and seizures over years, researchers found that IEA oscillates with circadian and subject-specific multiday periods. Multiday periodicities, most commonly 20–30 days in duration, are robust and relatively stable for as long as 10 years in men and women. Investigators also found that seizures occur preferentially during the rising phase of multiday IEA rhythms. Combining phase information from circadian and multiday IEA rhythms could be a biomarker for determining relative seizure risk with a large effect size in most subjects.
Baud MO, Kleen JK, Mirro EA, et al. Multi-day rhythms modulate seizure risk in epilepsy. Nat Commun. 2018;9(1):88.
DBS May Improve Survival in Parkinson’s Disease
Deep brain stimulation (DBS) is associated with a modest survival advantage when compared with medical management alone, according to a study published in the December 2017 issue of Movement Disorders. Investigators conducted a retrospective analysis of Veterans Affairs and Medicare administrative data of veterans with Parkinson’s disease between 2007 and 2013. They used propensity-score matching to pair patients who received DBS with those who received medical management alone. Veterans with Parkinson’s disease who received DBS had a longer survival measured in days than veterans who did not undergo DBS (2,291 days vs 2,064 days). Mean age at death was similar for both groups (76.5 vs 75.9), and the most common cause of death was Parkinson’s disease. The study groups may have differed in ways that are not measured.
Weaver FM, Stroupe KT, Smith B, et al. Survival in patients with Parkinson’s disease after deep brain stimulation or medical management. Mov Disord. 2017;32(12):1756-1763.
Idalopirdine May Not Decrease Cognitive Loss in Alzheimer’s Disease
In patients with mild to moderate Alzheimer’s disease, the use of idalopirdine, compared with placebo, does not improve cognition over 24 weeks of treatment, according to a study published January 9 in JAMA. The study examined three randomized clinical trials with 2,525 patients age 50 or older with mild to moderate Alzheimer’s disease. The 24-week studies were conducted from October 2013 to January 2017. Six months of 10 mg/day, 30 mg/day, or 60 mg/day idalopirdine treatment added to cholinesterase inhibitor therapy did not improve cognition or decrease cognitive loss. There was no requirement for evidence of Alzheimer’s disease biomarker positivity for inclusion in the trials, however, which may have allowed some patients to be included without having Alzheimer’s disease pathology.
Atri A, Frölich L, Ballard C, et al. Effect of idalopirdine as adjunct to cholinesterase inhibitors on change in cognition in patients with Alzheimer disease: three randomized clinical trials. JAMA. 2018;319(2):130-142.
New Biomarker May Identify Huntington’s Disease
A potential biomarker for Huntington’s disease could mean a more effective way of evaluating treatments for this neurologic disease, according to a study published online ahead of print December 27, 2017, in Neurology. Researchers studied miRNA levels in CSF from 30 asymptomatic carriers of the mutation that causes Huntington’s disease. They also studied CSF from participants diagnosed with Huntington’s disease, and from healthy controls. In all, 2,081 miRNAs were detected, and six were significantly increased in asymptomatic carriers versus controls. When the researchers evaluated the miRNA levels in each of the three patient groups, they found that all six had a pattern of increasing abundance from control to low risk, and from low risk to medium risk. The miRNA levels increase years before symptoms arise.
Reed ER, Latourelle JC, Bockholt JH, et al. MicroRNAs in CSF as prodromal biomarkers for Huntington disease in the PREDICT-HD study. Neurology. 2017 Dec 27 [Epub ahead of print].
Higher Topiramate Dose May Increase Risk of Cleft Lip or Palate
Topiramate increases the risk of cleft lip or cleft palate in offspring in a dose-dependent manner, according to a study published online ahead of print December 27, 2017, in Neurology. Researchers examined Medicaid data and identified approximately 1.4 million women who gave birth to live babies over 10 years. They compared women who filled a prescription for topiramate during their first trimester with women who did not fill a prescription for any antiseizure drug and women who filled a prescription for lamotrigine. The risk of oral clefts at birth was 4.1 per 1,000 in infants born to women exposed to topiramate, compared with 1.1 per 1,000 in the group unexposed to antiseizure drugs, and 1.5 per 1,000 among women exposed to lamotrigine.