Severe influenza is associated with greater odds of Parkinson’s disease, while measles reduces the odds of Parkinson’s disease, researchers reported in the July 2 online Movement Disorders. In this population-based, case-control study, the investigators examined 403 cases of Parkinson’s disease and 405 controls. Although there was an association between severe influenza and Parkinson’s disease (odds ratio, 2.01%), this effect was weaker when influenza reports were limited to those occurring 10 or more years before diagnosis. Conversely, childhood illness, particularly red measles (odds ratio, 0.65%), was associated with a lower risk of Parkinson’s disease. In addition, several animal exposures were linked with developing Parkinson’s disease, and these effects were statistically significant for exposure to cats (odds ratio, 2.06) and cattle (odds ratio, 2.23), the researchers noted.
Shift work is associated with an increased risk of vascular events such as heart attack and stroke, researchers reported in the July 26 online BMJ. The investigators conducted a meta-analysis of 34 studies that assessed risk ratios for vascular morbidity, vascular mortality, or all-cause mortality in relation to shift work. More than two million participants were included in the studies, in which 6,598 persons had myocardial infarctions, 17,359 had coronary events, and 1,854 had ischemic stroke. Results showed that shift work correlated with myocardial infarction (risk ratio,1.23), ischemic stroke (risk ratio, 1.05), and coronary events (risk ratio, 1.24), and these risks remained the same after adjustment for socioeconomic status and smoking. However, shift work was not associated with increased rates of overall mortality or mortality due to vascular causes.
Persons with higher levels of certain species of serum ceramides may have a greater risk of Alzheimer’s disease, according to research published in the online July 18 Neurology. The study included 99 women ages 70 to 79 who did not have dementia. Researchers recorded baseline levels of serum ceramides and sphingomyelins, as well as lipids, and followed the women for up to six visits over nine years, during which 27 women had incident dementia and 18 were diagnosed with probable Alzheimer’s disease. Analysis showed that higher baseline serum ceramides correlated with an increased risk of Alzheimer’s disease, while higher levels of sphingomyelins, total and high-density lipoprotein cholesterol, and triglycerides did not show a correlation with dementia or Alzheimer’s disease. The researchers noted that the study was preliminary and that the results warrant continued examination in larger studies.

Persons with advanced forms of relapsing–remitting multiple sclerosis (RRMS) show increasing levels of sodium concentration in their brains as the disease progresses, according to research published in the online July 17 Radiology. Using sodium 23 MRI, investigators measured brain sodium accumulations in 14 patients with early RRMS, 12 with advanced RRMS, and 15 controls. They found that total sodium concentrations increased inside demyelinating lesions in both groups of patients, but only patients with advanced RRMS showed increased total sodium concentrations in normal-appearing white matter and gray matter. Furthermore, increased total sodium concentration inside gray matter correlated with disability. Thus, brain sodium MRI may be helpful for monitoring the occurrence of tissue injury and disability, the researchers concluded.
The FDA has approved Gammagard liquid 10% (Immune Globulin Infusion [Human]) for treatment of multifocal motor neuropathy (MMN). The drug is the first immunoglobulin treatment approved in the US for patients with MMN, and its efficacy, safety, and tolerability were evaluated in a randomized, double-blind, placebo-controlled study. The study’s two coprimary end points were grip strength and disability in the more affected hand. According to the investigators, patients showed a relative change of 22.94% in mean grip strength in the more affected hand, compared with placebo. Furthermore, during the placebo period, most patients had functional deterioration and subsequently required an accelerated switch to Gammagard liquid. Although no study participants died or experienced unexpected serious adverse events, some patients had treatment-related pulmonary embolism and blurred vision.
The potassium channel KIR4.1 is the target of an autoantibody response in persons with multiple sclerosis (MS) and may serve as a potential diagnostic marker for MS, according to a study published in the July 12 New England Journal of Medicine. After screening serum IgG from patients with MS, researchers observed specific binding of IgG to glial cells in a subgroup of patients. The ATP-sensitive inward rectifying potassium channel KIR4.1 was identified as the target of the antibodies, and analysis of combined datasets showed that 186 of 397 persons with MS had the antibodies (46.9%), compared with three of 329 persons with other neurologic diseases (0.9%), and none of 59 healthy donors. “Serum levels of antibodies to KIR4.1 were higher in persons with MS than in persons with other neurologic diseases and healthy donors,” the researchers stated.
Fetal exposure to the pandemic influenza A[H1N1]pdm09 vaccine does not significantly increase the risk of adverse outcomes for infants, although adults exposed to the H1N1 vaccination have a small but significant risk of Guillain-Barré syndrome. Researchers reported these results in two studies published in the July 11 JAMA. The first study included data from all liveborn singleton infants in Denmark. Of those infants, 53,432 were exposed to the H1N1 vaccine in utero, and exposure was not associated with a significantly increased risk of major birth defects, preterm birth, or fetal growth restriction. The second study followed up on an immunization campaign in Quebec in which 57% of the 7.8 million residents were vaccinated. There were 83 cases of Guillain-Barré identified during a six-month period. According to investigators, approximately two cases of Guillain-Barré syndrome were attributable to vaccination per one million doses. However, they noted that the benefits of immunization likely outweigh the risks.
A 24-week treatment period of stress management therapy reduces new gadolinium-enhancing brain lesions in patients with relapsing forms of multiple sclerosis (MS) while they are in treatment, researchers reported in the July 11 online Neurology. The study included 121 patients who were randomized to a wait-list control condition or to stress management therapy for MS (SMT-MS), which consisted of 16 individual treatment sessions for 24 weeks, followed by a 24-week post-treatment period. The primary outcome was the cumulative number of new gadolinium-enhancing lesions on MRI at weeks 8, 16, and 24. Compared with controls, more patients who received SMT-MS remained free of new lesions, and these patients also showed a reduction in new lesions compared with controls. However, the positive effects of SMT-MS were not detectable during the 24-week post-treatment period. Researchers concluded that SMT-MS may be useful in reducing the development of new brain lesions during treatment.
Patients with stroke who are admitted to the hospital on the weekend are less likely to receive urgent care and more likely to have worse overall outcomes, according to a study in the July 9 online Archives of Neurology. Researchers retrospectively evaluated data from 93,621 patients with stroke who were admitted to hospitals from April 1, 2009, to March 31, 2010. Logistic regression was used to measure six indicators of hospital care, and results showed significantly lower performance on weekends across five of the six measures. For example, rates of same-day brain scans were 43.1% on weekends and 47.6% on weekdays, and the rate of seven-day in-hospital mortality for Sunday admissions was 11.0% versus 8.9% for weekday admissions. Replicating weekday performance on weekends is likely to improve patient outcomes, the researchers concluded.
A coding mutation in the amyloid-b precursor protein (APP) gene protects against cognitive decline in older persons who do not have Alzheimer’s disease, according to a study published in the online July 11 Nature. Researchers identified the beneficial coding mutation (A673T) in the APP gene after studying coding variants in APP in a set of whole-genome sequence data from 1,795 Icelanders. The mutation leads to an approximately 40% reduction in the formation of amyloidogenic peptides in vitro, and it provides support for the hypothesis that reducing b-cleavage of APP may protect against Alzheimer’s disease. “As the A673T allele also protects against cognitive decline in the elderly without Alzheimer’s disease, the two may be mediated through the same or similar mechanisms,” the study authors wrote.

—Lauren LeBano

New and Noteworthy Information—August