New and Noteworthy Information—October 2017
Mononucleosis May Increase Risk of MS
Epstein-Barr nuclear antigen-1 seropositivty is independently associated with increased risk of multiple sclerosis (MS) or clinically isolated syndrome (CIS), according to a study published online ahead of print August 30 in Neurology. Researchers recruited 1,090 black, Hispanic, and white people with MS or CIS and matched controls over a three-year period. Participants were tested for the Epstein-Barr virus antibody and were asked whether they had ever had mononucleosis. Blacks who had had mononucleosis were more than four times more likely to develop MS, compared with those who had not had mononucleosis. Hispanics and whites who had had mononucleosis were nearly four times and two times, respectively, more likely to develop MS or CIS, compared with those who had not had mononucleosis.
Langer-Gould A, Wu J, Lucas R, et al. Epstein-Barr virus, cytomegalovirus, and multiple sclerosis susceptibility: a multiethnic study. Neurology. 2017 Aug 30 [Epub ahead of print].
Asthma Medicine May Decrease Risk of Parkinson’s Disease
Salbutamol, a brain-penetrant asthma medication, is associated with reduced risk of Parkinson’s disease, according to a study published September 1 in Science. Researchers used an unbiased screen targeting endogenous gene expression to discover that the β2-adrenoreceptor (β2AR) is a regulator of the α-synuclein gene. Research has indicated that excess production of α-synuclein may be a causative factor in Parkinson’s disease. Over 11 years of follow-up in four million Norwegians, the β2AR agonist salbutamol was associated with reduced risk of Parkinson’s disease (rate ratio, 0.66). A β2AR antagonist correlated with increased risk.
Mittal S, Bjørnevik K, Im DS, et al. β2-Adrenoreceptor is a regulator of the α-synuclein gene driving risk of Parkinson’s disease. Science. 2017;357(6354):891-898 [Epub ahead of print].
Odds of Developing Alzheimer’s Disease Same for Men and Women With APOE Genotype
Men and women with the APOE ε3/ε4 genotype have nearly the same odds of developing Alzheimer’s disease from age 55 to 85, but women have an increased risk at younger ages, according to a study published online ahead of print August 28 in JAMA Neurology. Researchers analyzed data from 27 studies with nearly 58,000 participants. Homogeneous data sets were pooled in case-control analyses, and logistic regression models were used to compute risks. Age-adjusted odds ratios and 95% confidence intervals for developing mild cognitive impairment and Alzheimer’s disease were calculated for men and women across APOE genotypes. Men and women with the APOE ε3/ε4 genotype from ages 55 to 85 did not show a difference in Alzheimer’s disease risk. Women had an increased risk of Alzheimer’s disease compared with men between the ages of 65 and 75.
Neu SC, Pa J, Kukull W, et al. Apolipoprotein e genotype and sex risk factors for Alzheimer disease: a meta-analysis. JAMA Neurol. 2017 Aug 28 [Epub ahead of print].
Does Dimethyl Fumarate Prevent MS Reactivation After Natalizumab Discontinuation?
Dimethyl fumarate appears generally safe and may be a promising drug for patients at high risk of progressive multifocal leukoencephalopathy (PML) who discontinue natalizumab, according to an article published online ahead of print August 26 in the Journal of Neurology, Neurosurgery and Psychiatry. Thirty-nine patients with relapsing-remitting multiple sclerosis (MS) at high risk of PML were switched from natalizumab to dimethyl fumarate and underwent neurologic and 3T MRI monitoring for two years. Clinical and MRI data regarding the two-year period preceding natalizumab treatment, the two years of natalizumab treatment, and the two years of dimethyl fumarate treatment were collected. During the dimethyl fumarate phase, one or more relapses occurred in five patients (12.8%), increased disability progression occurred in four patients (10.3%), and MRI activity occurred in eight patients (20.5%). Post-natalizumab rebound effect was observed in one patient. Almost 80% of the patients had no evidence of disease activity after two years of dimethyl fumarate treatment. No carryover PML among investigated cases was observed.
Calabrese M, Pitteri M, Farina G, et al. Dimethyl fumarate: a possible exit strategy from natalizumab treatment in patients with multiple sclerosis at risk for severe adverse events. J Neurol Neurosurg Psychiatry. 2017 Aug 26 [Epub ahead of print].
Austedo Approved for Treatment of Tardive Dyskinesia in Adults
The FDA has approved Austedo (deutetrabenazine) tablets for the treatment of tardive dyskinesia in adults. The approval was based on results from two phase III randomized, double-blind, placebo-controlled, parallel group studies assessing the efficacy and safety of Austedo in reducing the severity of abnormal involuntary movements associated with tardive dyskinesia. Austedo was previously approved in April for the treatment of chorea associated with Huntington’s disease. The most common adverse reactions (ie, 4% of Austedo-treated patients and greater than placebo) in controlled clinical studies of patients with tardive dyskinesia were nasopharyngitis and insomnia. Teva Pharmaceutical Industries, which markets Austedo, is headquartered in Jerusalem.
