New and Noteworthy Information—March 2015

Moderate physical activity is associated with a lower risk of coronary heart disease, venous thromboembolic events, and cerebrovascular disease in women, according to a study published online ahead of print February 16 in Circulation. Participants included 1.1 million women in the United Kingdom with no history of cancer, heart disease, stroke, blood clots, or diabetes who joined the Million Women study between 1996 and 2001. Their average age when they joined the study was 56. Women who performed strenuous physical activity two to three times per week were 20% less likely to develop heart disease, strokes, or blood clots, compared with participants who reported little or no activity. More frequent physical activity did not result in further reductions in the risk of heart disease.

The FDA has approved Rytary, an extended-release oral capsule formulation of carbidopa–levodopa, for the treatment of Parkinson’s disease, post-encephalitic parkinsonism, and parkinsonism that may follow carbon monoxide intoxication or manganese intoxication. Rytary contains immediate-release and extended-release beads that contain carbidopa and levodopa in a 1:4 ratio, and provides initial and extended levodopa plasma concentrations after a single dose. In a trial of 393 randomized patients with advanced Parkinson’s disease, treatment with Rytary reduced the percentage of off time during waking hours from baseline to the end of the study, versus immediate-release carbidopa–levodopa. Rytary may be swallowed whole or opened, and the beads may be sprinkled on applesauce and consumed immediately. The drug is manufactured by Impax Pharmaceuticals (Hayward, California).

The FDA has approved Duopa, an enteral suspension of carbidopa and levodopa, as an orphan drug for the treatment of motor fluctuations in people with advanced Parkinson’s disease. The approval of Duopa is based on a phase III, 12-week, double-blind, double-placebo, active control, parallel-group, multicenter trial that compared the efficacy and safety of Duopa with that of oral, immediate-release carbidopa–levodopa tablets in patients with advanced Parkinson’s disease. Duopa significantly reduced daily mean off time at 12 weeks by four hours, which resulted in an average of 1.9 fewer hours of off time, when compared with carbidopa–levodopa tablets. Duopa is administered using a small, portable infusion pump that delivers carbidopa and levodopa directly into the small intestine continuously for 16 hours via a surgically-placed tube. The drug is manufactured by AbbVie (North Chicago, Illinois).

A link exists between brain structure and postconcussive symptoms among young male athletes who are otherwise healthy, according to a study published in the February issue of the Journal of Pediatrics. Researchers used advanced imaging technology and cognitive testing to assess 29 ice hockey players between ages 14 and 23, some of whom had a sports-related concussion. As the severity of the athletes’ concussion symptoms increased, the cortex became thinner in areas of the brain where it should be dense for players of these ages. Investigators believe that injury to a developing brain may be more severe than injury to an adult brain. “Years of playing contact sports and repeatedly getting your head knocked around probably is not good for the brain, especially in young children whose brains are still maturing,” the researchers stated.

Children whose urine drug screens tested positive for tetrahydrocannabinol (THC) met multiple sleep latency tests (MSLT) criteria for narcolepsy or had multiple sleep-onset REM periods, according to a study published January 15 in Journal of Clinical Sleep Medicine. The 10-year retrospective study included 383 children who underwent drug screens on the morning before MSLT. Of children with urine drug screens that were positive for marijuana, 43% had MSLT results consistent with narcolepsy or abnormal REM sleep patterns. Approximately 24% of children who tested negative for marijuana had MSLT results consistent with narcolepsy. No child younger than 13 had a positive urine drug screen. Males were more likely to have a positive urine drug screen and MSLT findings that were consistent with narcolepsy, compared with other groups.

Low plasma levels of APOE are associated with increased risk of future Alzheimer’s disease and all dementia in the general population, independent of ε2, ε3, and ε4 APOE genotype, according to a study published in the February issue of Annals of Neurology. The study included 75,708 participants. Multifactorially adjusted hazard ratios for lowest versus highest APOE tertile were 2.68 and 1.80 for Alzheimer’s disease and all dementia, respectively. After further adjustment for APOE genotype, plasma APOE tertiles remained associated with Alzheimer’s disease and all dementia. Researchers determined that the low level of APOE in the blood reflects a low level of APOE in the brain, indicating that β-amyloid is less effectively removed. Plasma levels of APOE may be a new, easily accessible preclinical biomarker, said the authors.

Women with Alzheimer’s disease had stable cognition for a year when they received leuprolide acetate, according to a study published in the January 1 issue of Journal of Alzheimer’s Disease. The clinical trial followed 109 women with mild to moderate Alzheimer’s disease who were randomized to low-dose leuprolide acetate, high-dose leuprolide acetate, or placebo. Among patients taking an acetylcholinesterase inhibitor, researchers saw a statistically significant benefit in the high-dose leuprolide acetate group, compared with the other groups, as determined by the Alzheimer’s Disease Assessment Scale-cognitive subscale. Mean decline was 0.18 for the high-dose group, 4.21 for the low-dose group, and 3.30 for the placebo group. “This is the first time any therapy has been shown to stabilize memory loss over a year,” the researchers said.

The rate of favorable seizure outcome or seizure freedom after resective epilepsy surgery is significant and remains stable for more than 15 years, according to a study published online ahead of print January 19 in Epilepsy & Behavior. The findings were based on a telephone survey of 253 patients who underwent resection to treat localization-related epilepsy during an 18-year period. The mean age at the time of surgery was 35.4, with a range from five months to 71. Investigators found that 92% of patients surveyed considered epilepsy surgery worthwhile, 32% were seizure-free, and 75% had favorable results. Favorable and seizure-free outcome rates remained stable after surgery over long-term follow-up. Compared with baseline, patients were more likely to be driving and taking antidepressant medication, but less likely to be employed full-time after surgery.

Nearly one in five adults with epilepsy has symptoms of attention deficit hyperactivity disorder (ADHD), which are associated with increased psychosocial morbidity and lowered quality of life, according to a study published online ahead of print January 15 in Epilepsia. In the study, researchers mailed a survey to a national sample of adult patients with epilepsy, as part of the Epilepsy Comorbidities and Health study. The relationship of ADHD symptoms to quality of life outcomes was examined using statistical analyses, which also looked at sociodemographics, depression, anxiety, seizure frequency, and number of antiepileptic drugs. Nearly one-fifth (18.4%) of 1,361 respondents with active epilepsy were classified as experiencing significant ADHD symptoms. “This study reinforces the fact that we have to broaden our view of what epilepsy entails,” said the investigators.

Triheptanoin corrects the bioenergetic profile in the brain of patients with Huntington’s disease early in the course of the disease, according to a study published online ahead of print January 7 in Neurology. Researchers used MRI brain scans to analyze the energy profile before, during, and after the brain was visually stimulated in nine people in the early stages of Huntington’s disease and 13 people without the disease. In the people without the disease, the brain’s metabolism increased during the stimulation, then returned to the normal level. In people with Huntington’s disease, there was no change in metabolism. For the second part of the study, participants with Huntington’s disease received triheptanoin. When these participants underwent the visual stimulation test again, their brain metabolism was normal.

A common gut microbe may curb the risk of developing multiple sclerosis (MS) in women, according to a study published online ahead of print January 19 in the Journal of Neurology, Neurosurgery & Psychiatry. Researchers tested 550 people with confirmed MS and a comparison group of 299 healthy people, matched for age and sex, for antibodies to H. pylori between 2007 and 2011. The prevalence of the infection was significantly lower in participants with MS than in the comparison group, but only among women, in whom it was 30% lower. Among men, a positive test result was linked to higher rates of disability, but a positive test was associated with lower disability among women. The researchers found no evidence of any link between the presence of the infection and relapse rate.

Among patients with relapsing-remitting multiple sclerosis (MS), nonmyeloablative hematopoietic stem cell transplantation is associated with improvement in neurologic disability and other clinical outcomes, according to a study published January 20 in JAMA. In a case series of patients with relapsing-remitting MS or secondary progressive MS, participants received transplantation and were followed up for five years. In all, 41 patients (50%) had significant improvement in Expanded Disability Status Scale score at two years, and 23 patients (64%) had significant improvement at four years. Receipt of hematopoietic stem cell transplantation was associated with improvement in physical function, cognitive function, and quality of life. In addition, treatment was associated with a reduction in the volume of brain lesions associated with MS seen on MRI.

Insomnia in childhood and adolescence partially results from genetic factors, according to a study published in the January issue of Sleep. The study group included 1,412 twin pairs between the ages of 8 and 18. Participants were followed-up at three time points. The average ages at each of the four stages of the study were 8, 10, 14, and 15. The results showed that clinically significant insomnia was moderately heritable at all stages of the longitudinal study. Genetic factors contributed 33% to 38% of the insomnia ratings at the first two stages of the study, when participants were an average age of 8 to 10. “Insomnia in youth is moderately related to genetic factors, but the specific genetic factors may change with age,” stated the investigators.

People with epilepsy who sleep on their stomach may be at a higher risk of sudden unexpected death, according to a literature review published online ahead of print January 21 in Neurology. Researchers found that 73% of the deaths occurred while individuals were sleeping on their stomachs, compared with 27% of deaths that occurred during other sleep positions. In a subgroup of 88 people, researchers found that people younger than 40 were four times more likely to be found on their stomach at the time of sudden death than people older than 40. A total of 86% of those under 40 slept on their stomach, compared with 60% of people older than 40. Eleven sudden deaths occurred while the participants were being monitored with video EEG.

—Kimberly D. Williams

Moderate physical activity is associated with a lower risk of coronary heart disease, venous thromboembolic events, and cerebrovascular disease in women, according to a study published online ahead of print February 16 in Circulation. Participants included 1.1 million women in the United Kingdom with no history of cancer, heart disease, stroke, blood clots, or diabetes who joined the Million Women study between 1996 and 2001. Their average age when they joined the study was 56. Women who performed strenuous physical activity two to three times per week were 20% less likely to develop heart disease, strokes, or blood clots, compared with participants who reported little or no activity. More frequent physical activity did not result in further reductions in the risk of heart disease.

The FDA has approved Rytary, an extended-release oral capsule formulation of carbidopa–levodopa, for the treatment of Parkinson’s disease, post-encephalitic parkinsonism, and parkinsonism that may follow carbon monoxide intoxication or manganese intoxication. Rytary contains immediate-release and extended-release beads that contain carbidopa and levodopa in a 1:4 ratio, and provides initial and extended levodopa plasma concentrations after a single dose. In a trial of 393 randomized patients with advanced Parkinson’s disease, treatment with Rytary reduced the percentage of off time during waking hours from baseline to the end of the study, versus immediate-release carbidopa–levodopa. Rytary may be swallowed whole or opened, and the beads may be sprinkled on applesauce and consumed immediately. The drug is manufactured by Impax Pharmaceuticals (Hayward, California).

The FDA has approved Duopa, an enteral suspension of carbidopa and levodopa, as an orphan drug for the treatment of motor fluctuations in people with advanced Parkinson’s disease. The approval of Duopa is based on a phase III, 12-week, double-blind, double-placebo, active control, parallel-group, multicenter trial that compared the efficacy and safety of Duopa with that of oral, immediate-release carbidopa–levodopa tablets in patients with advanced Parkinson’s disease. Duopa significantly reduced daily mean off time at 12 weeks by four hours, which resulted in an average of 1.9 fewer hours of off time, when compared with carbidopa–levodopa tablets. Duopa is administered using a small, portable infusion pump that delivers carbidopa and levodopa directly into the small intestine continuously for 16 hours via a surgically-placed tube. The drug is manufactured by AbbVie (North Chicago, Illinois).

A link exists between brain structure and postconcussive symptoms among young male athletes who are otherwise healthy, according to a study published in the February issue of the Journal of Pediatrics. Researchers used advanced imaging technology and cognitive testing to assess 29 ice hockey players between ages 14 and 23, some of whom had a sports-related concussion. As the severity of the athletes’ concussion symptoms increased, the cortex became thinner in areas of the brain where it should be dense for players of these ages. Investigators believe that injury to a developing brain may be more severe than injury to an adult brain. “Years of playing contact sports and repeatedly getting your head knocked around probably is not good for the brain, especially in young children whose brains are still maturing,” the researchers stated.

Children whose urine drug screens tested positive for tetrahydrocannabinol (THC) met multiple sleep latency tests (MSLT) criteria for narcolepsy or had multiple sleep-onset REM periods, according to a study published January 15 in Journal of Clinical Sleep Medicine. The 10-year retrospective study included 383 children who underwent drug screens on the morning before MSLT. Of children with urine drug screens that were positive for marijuana, 43% had MSLT results consistent with narcolepsy or abnormal REM sleep patterns. Approximately 24% of children who tested negative for marijuana had MSLT results consistent with narcolepsy. No child younger than 13 had a positive urine drug screen. Males were more likely to have a positive urine drug screen and MSLT findings that were consistent with narcolepsy, compared with other groups.

Low plasma levels of APOE are associated with increased risk of future Alzheimer’s disease and all dementia in the general population, independent of ε2, ε3, and ε4 APOE genotype, according to a study published in the February issue of Annals of Neurology. The study included 75,708 participants. Multifactorially adjusted hazard ratios for lowest versus highest APOE tertile were 2.68 and 1.80 for Alzheimer’s disease and all dementia, respectively. After further adjustment for APOE genotype, plasma APOE tertiles remained associated with Alzheimer’s disease and all dementia. Researchers determined that the low level of APOE in the blood reflects a low level of APOE in the brain, indicating that β-amyloid is less effectively removed. Plasma levels of APOE may be a new, easily accessible preclinical biomarker, said the authors.

Women with Alzheimer’s disease had stable cognition for a year when they received leuprolide acetate, according to a study published in the January 1 issue of Journal of Alzheimer’s Disease. The clinical trial followed 109 women with mild to moderate Alzheimer’s disease who were randomized to low-dose leuprolide acetate, high-dose leuprolide acetate, or placebo. Among patients taking an acetylcholinesterase inhibitor, researchers saw a statistically significant benefit in the high-dose leuprolide acetate group, compared with the other groups, as determined by the Alzheimer’s Disease Assessment Scale-cognitive subscale. Mean decline was 0.18 for the high-dose group, 4.21 for the low-dose group, and 3.30 for the placebo group. “This is the first time any therapy has been shown to stabilize memory loss over a year,” the researchers said.

The rate of favorable seizure outcome or seizure freedom after resective epilepsy surgery is significant and remains stable for more than 15 years, according to a study published online ahead of print January 19 in Epilepsy & Behavior. The findings were based on a telephone survey of 253 patients who underwent resection to treat localization-related epilepsy during an 18-year period. The mean age at the time of surgery was 35.4, with a range from five months to 71. Investigators found that 92% of patients surveyed considered epilepsy surgery worthwhile, 32% were seizure-free, and 75% had favorable results. Favorable and seizure-free outcome rates remained stable after surgery over long-term follow-up. Compared with baseline, patients were more likely to be driving and taking antidepressant medication, but less likely to be employed full-time after surgery.

Nearly one in five adults with epilepsy has symptoms of attention deficit hyperactivity disorder (ADHD), which are associated with increased psychosocial morbidity and lowered quality of life, according to a study published online ahead of print January 15 in Epilepsia. In the study, researchers mailed a survey to a national sample of adult patients with epilepsy, as part of the Epilepsy Comorbidities and Health study. The relationship of ADHD symptoms to quality of life outcomes was examined using statistical analyses, which also looked at sociodemographics, depression, anxiety, seizure frequency, and number of antiepileptic drugs. Nearly one-fifth (18.4%) of 1,361 respondents with active epilepsy were classified as experiencing significant ADHD symptoms. “This study reinforces the fact that we have to broaden our view of what epilepsy entails,” said the investigators.

Triheptanoin corrects the bioenergetic profile in the brain of patients with Huntington’s disease early in the course of the disease, according to a study published online ahead of print January 7 in Neurology. Researchers used MRI brain scans to analyze the energy profile before, during, and after the brain was visually stimulated in nine people in the early stages of Huntington’s disease and 13 people without the disease. In the people without the disease, the brain’s metabolism increased during the stimulation, then returned to the normal level. In people with Huntington’s disease, there was no change in metabolism. For the second part of the study, participants with Huntington’s disease received triheptanoin. When these participants underwent the visual stimulation test again, their brain metabolism was normal.

A common gut microbe may curb the risk of developing multiple sclerosis (MS) in women, according to a study published online ahead of print January 19 in the Journal of Neurology, Neurosurgery & Psychiatry. Researchers tested 550 people with confirmed MS and a comparison group of 299 healthy people, matched for age and sex, for antibodies to H. pylori between 2007 and 2011. The prevalence of the infection was significantly lower in participants with MS than in the comparison group, but only among women, in whom it was 30% lower. Among men, a positive test result was linked to higher rates of disability, but a positive test was associated with lower disability among women. The researchers found no evidence of any link between the presence of the infection and relapse rate.

Among patients with relapsing-remitting multiple sclerosis (MS), nonmyeloablative hematopoietic stem cell transplantation is associated with improvement in neurologic disability and other clinical outcomes, according to a study published January 20 in JAMA. In a case series of patients with relapsing-remitting MS or secondary progressive MS, participants received transplantation and were followed up for five years. In all, 41 patients (50%) had significant improvement in Expanded Disability Status Scale score at two years, and 23 patients (64%) had significant improvement at four years. Receipt of hematopoietic stem cell transplantation was associated with improvement in physical function, cognitive function, and quality of life. In addition, treatment was associated with a reduction in the volume of brain lesions associated with MS seen on MRI.

Insomnia in childhood and adolescence partially results from genetic factors, according to a study published in the January issue of Sleep. The study group included 1,412 twin pairs between the ages of 8 and 18. Participants were followed-up at three time points. The average ages at each of the four stages of the study were 8, 10, 14, and 15. The results showed that clinically significant insomnia was moderately heritable at all stages of the longitudinal study. Genetic factors contributed 33% to 38% of the insomnia ratings at the first two stages of the study, when participants were an average age of 8 to 10. “Insomnia in youth is moderately related to genetic factors, but the specific genetic factors may change with age,” stated the investigators.

People with epilepsy who sleep on their stomach may be at a higher risk of sudden unexpected death, according to a literature review published online ahead of print January 21 in Neurology. Researchers found that 73% of the deaths occurred while individuals were sleeping on their stomachs, compared with 27% of deaths that occurred during other sleep positions. In a subgroup of 88 people, researchers found that people younger than 40 were four times more likely to be found on their stomach at the time of sudden death than people older than 40. A total of 86% of those under 40 slept on their stomach, compared with 60% of people older than 40. Eleven sudden deaths occurred while the participants were being monitored with video EEG.

—Kimberly D. Williams

Moderate physical activity is associated with a lower risk of coronary heart disease, venous thromboembolic events, and cerebrovascular disease in women, according to a study published online ahead of print February 16 in Circulation. Participants included 1.1 million women in the United Kingdom with no history of cancer, heart disease, stroke, blood clots, or diabetes who joined the Million Women study between 1996 and 2001. Their average age when they joined the study was 56. Women who performed strenuous physical activity two to three times per week were 20% less likely to develop heart disease, strokes, or blood clots, compared with participants who reported little or no activity. More frequent physical activity did not result in further reductions in the risk of heart disease.

The FDA has approved Rytary, an extended-release oral capsule formulation of carbidopa–levodopa, for the treatment of Parkinson’s disease, post-encephalitic parkinsonism, and parkinsonism that may follow carbon monoxide intoxication or manganese intoxication. Rytary contains immediate-release and extended-release beads that contain carbidopa and levodopa in a 1:4 ratio, and provides initial and extended levodopa plasma concentrations after a single dose. In a trial of 393 randomized patients with advanced Parkinson’s disease, treatment with Rytary reduced the percentage of off time during waking hours from baseline to the end of the study, versus immediate-release carbidopa–levodopa. Rytary may be swallowed whole or opened, and the beads may be sprinkled on applesauce and consumed immediately. The drug is manufactured by Impax Pharmaceuticals (Hayward, California).

The FDA has approved Duopa, an enteral suspension of carbidopa and levodopa, as an orphan drug for the treatment of motor fluctuations in people with advanced Parkinson’s disease. The approval of Duopa is based on a phase III, 12-week, double-blind, double-placebo, active control, parallel-group, multicenter trial that compared the efficacy and safety of Duopa with that of oral, immediate-release carbidopa–levodopa tablets in patients with advanced Parkinson’s disease. Duopa significantly reduced daily mean off time at 12 weeks by four hours, which resulted in an average of 1.9 fewer hours of off time, when compared with carbidopa–levodopa tablets. Duopa is administered using a small, portable infusion pump that delivers carbidopa and levodopa directly into the small intestine continuously for 16 hours via a surgically-placed tube. The drug is manufactured by AbbVie (North Chicago, Illinois).

A link exists between brain structure and postconcussive symptoms among young male athletes who are otherwise healthy, according to a study published in the February issue of the Journal of Pediatrics. Researchers used advanced imaging technology and cognitive testing to assess 29 ice hockey players between ages 14 and 23, some of whom had a sports-related concussion. As the severity of the athletes’ concussion symptoms increased, the cortex became thinner in areas of the brain where it should be dense for players of these ages. Investigators believe that injury to a developing brain may be more severe than injury to an adult brain. “Years of playing contact sports and repeatedly getting your head knocked around probably is not good for the brain, especially in young children whose brains are still maturing,” the researchers stated.

Children whose urine drug screens tested positive for tetrahydrocannabinol (THC) met multiple sleep latency tests (MSLT) criteria for narcolepsy or had multiple sleep-onset REM periods, according to a study published January 15 in Journal of Clinical Sleep Medicine. The 10-year retrospective study included 383 children who underwent drug screens on the morning before MSLT. Of children with urine drug screens that were positive for marijuana, 43% had MSLT results consistent with narcolepsy or abnormal REM sleep patterns. Approximately 24% of children who tested negative for marijuana had MSLT results consistent with narcolepsy. No child younger than 13 had a positive urine drug screen. Males were more likely to have a positive urine drug screen and MSLT findings that were consistent with narcolepsy, compared with other groups.

Low plasma levels of APOE are associated with increased risk of future Alzheimer’s disease and all dementia in the general population, independent of ε2, ε3, and ε4 APOE genotype, according to a study published in the February issue of Annals of Neurology. The study included 75,708 participants. Multifactorially adjusted hazard ratios for lowest versus highest APOE tertile were 2.68 and 1.80 for Alzheimer’s disease and all dementia, respectively. After further adjustment for APOE genotype, plasma APOE tertiles remained associated with Alzheimer’s disease and all dementia. Researchers determined that the low level of APOE in the blood reflects a low level of APOE in the brain, indicating that β-amyloid is less effectively removed. Plasma levels of APOE may be a new, easily accessible preclinical biomarker, said the authors.

Women with Alzheimer’s disease had stable cognition for a year when they received leuprolide acetate, according to a study published in the January 1 issue of Journal of Alzheimer’s Disease. The clinical trial followed 109 women with mild to moderate Alzheimer’s disease who were randomized to low-dose leuprolide acetate, high-dose leuprolide acetate, or placebo. Among patients taking an acetylcholinesterase inhibitor, researchers saw a statistically significant benefit in the high-dose leuprolide acetate group, compared with the other groups, as determined by the Alzheimer’s Disease Assessment Scale-cognitive subscale. Mean decline was 0.18 for the high-dose group, 4.21 for the low-dose group, and 3.30 for the placebo group. “This is the first time any therapy has been shown to stabilize memory loss over a year,” the researchers said.

The rate of favorable seizure outcome or seizure freedom after resective epilepsy surgery is significant and remains stable for more than 15 years, according to a study published online ahead of print January 19 in Epilepsy & Behavior. The findings were based on a telephone survey of 253 patients who underwent resection to treat localization-related epilepsy during an 18-year period. The mean age at the time of surgery was 35.4, with a range from five months to 71. Investigators found that 92% of patients surveyed considered epilepsy surgery worthwhile, 32% were seizure-free, and 75% had favorable results. Favorable and seizure-free outcome rates remained stable after surgery over long-term follow-up. Compared with baseline, patients were more likely to be driving and taking antidepressant medication, but less likely to be employed full-time after surgery.

Nearly one in five adults with epilepsy has symptoms of attention deficit hyperactivity disorder (ADHD), which are associated with increased psychosocial morbidity and lowered quality of life, according to a study published online ahead of print January 15 in Epilepsia. In the study, researchers mailed a survey to a national sample of adult patients with epilepsy, as part of the Epilepsy Comorbidities and Health study. The relationship of ADHD symptoms to quality of life outcomes was examined using statistical analyses, which also looked at sociodemographics, depression, anxiety, seizure frequency, and number of antiepileptic drugs. Nearly one-fifth (18.4%) of 1,361 respondents with active epilepsy were classified as experiencing significant ADHD symptoms. “This study reinforces the fact that we have to broaden our view of what epilepsy entails,” said the investigators.

Triheptanoin corrects the bioenergetic profile in the brain of patients with Huntington’s disease early in the course of the disease, according to a study published online ahead of print January 7 in Neurology. Researchers used MRI brain scans to analyze the energy profile before, during, and after the brain was visually stimulated in nine people in the early stages of Huntington’s disease and 13 people without the disease. In the people without the disease, the brain’s metabolism increased during the stimulation, then returned to the normal level. In people with Huntington’s disease, there was no change in metabolism. For the second part of the study, participants with Huntington’s disease received triheptanoin. When these participants underwent the visual stimulation test again, their brain metabolism was normal.

A common gut microbe may curb the risk of developing multiple sclerosis (MS) in women, according to a study published online ahead of print January 19 in the Journal of Neurology, Neurosurgery & Psychiatry. Researchers tested 550 people with confirmed MS and a comparison group of 299 healthy people, matched for age and sex, for antibodies to H. pylori between 2007 and 2011. The prevalence of the infection was significantly lower in participants with MS than in the comparison group, but only among women, in whom it was 30% lower. Among men, a positive test result was linked to higher rates of disability, but a positive test was associated with lower disability among women. The researchers found no evidence of any link between the presence of the infection and relapse rate.

Among patients with relapsing-remitting multiple sclerosis (MS), nonmyeloablative hematopoietic stem cell transplantation is associated with improvement in neurologic disability and other clinical outcomes, according to a study published January 20 in JAMA. In a case series of patients with relapsing-remitting MS or secondary progressive MS, participants received transplantation and were followed up for five years. In all, 41 patients (50%) had significant improvement in Expanded Disability Status Scale score at two years, and 23 patients (64%) had significant improvement at four years. Receipt of hematopoietic stem cell transplantation was associated with improvement in physical function, cognitive function, and quality of life. In addition, treatment was associated with a reduction in the volume of brain lesions associated with MS seen on MRI.

Insomnia in childhood and adolescence partially results from genetic factors, according to a study published in the January issue of Sleep. The study group included 1,412 twin pairs between the ages of 8 and 18. Participants were followed-up at three time points. The average ages at each of the four stages of the study were 8, 10, 14, and 15. The results showed that clinically significant insomnia was moderately heritable at all stages of the longitudinal study. Genetic factors contributed 33% to 38% of the insomnia ratings at the first two stages of the study, when participants were an average age of 8 to 10. “Insomnia in youth is moderately related to genetic factors, but the specific genetic factors may change with age,” stated the investigators.

People with epilepsy who sleep on their stomach may be at a higher risk of sudden unexpected death, according to a literature review published online ahead of print January 21 in Neurology. Researchers found that 73% of the deaths occurred while individuals were sleeping on their stomachs, compared with 27% of deaths that occurred during other sleep positions. In a subgroup of 88 people, researchers found that people younger than 40 were four times more likely to be found on their stomach at the time of sudden death than people older than 40. A total of 86% of those under 40 slept on their stomach, compared with 60% of people older than 40. Eleven sudden deaths occurred while the participants were being monitored with video EEG.

—Kimberly D. Williams