New and Noteworthy Information—May

Adults with a higher level of daily physical activity may have a decreased risk of Alzheimer’s disease, according to research published in the online April 18 Neurology. Researchers objectively measured the continuous exercise and nonexercise physical activity of 716 older subjects without dementia by using actigraphy monitoring for up to 10 days. During an average follow-up of four years, 71 persons were diagnosed with clinical Alzheimer’s disease, and the investigators identified an inverse association between total daily physical activity and Alzheimer’s disease (hazard ratio, 0.477) after adjusting for age, sex, and education. This association remained following further adjustments for self-reported physical, social, and cognitive activities; APOE allele status; and current level of motor function, depressive symptoms, and chronic health conditions. “A higher level of total daily physical activity is associated with reduced risk of Alzheimer’s disease,” the investigators concluded.

The herpes zoster vaccine is associated with a small increased risk of allergic reactions in the week following vaccination but is generally safe and well tolerated, according to a study published in the May Journal of Internal Medicine. Researchers analyzed data from 193,083 persons ages 50 and older who had received a zoster vaccine from January 2007 to December 2008 and who were included in the Vaccine Safety Datalink project. A case-centered approach and a self-controlled case series approach were used for analysis. Although results showed that risk of allergic reaction significantly increased within one to seven days of vaccination (RR, 2.13), the investigators identified no increased risk for cerebrovascular or cardiovascular events, meningitis, encephalitis, encephalopathy, Ramsay–Hunt syndrome, or Bell’s palsy. According to the study authors, this research supports the safety results from the zoster vaccine’s prelicensure clinical trials.

Consumption of low-fat dairy products may reduce the risk of stroke, according to research published in the online April 19 Stroke. In a prospective cohort study, researchers followed 74,961 Swedish women and men who were free from cancer and cardiovascular disease. During a mean 10.2-year follow-up, 4,089 cases of stroke were recorded among the cohort, including 3,159 cerebral infarctions, 583 hemorrhagic strokes, and 347 unspecified strokes. Analysis showed an inverse association between consumption of low-fat dairy food and risk of total stroke and cerebral infarction, with multivariable relative risks for the highest compared with the lowest quintile of low-fat dairy consumption of .88 for total stroke and .87 for cerebral infarction. “These results suggest that low-fat dairy consumption is inversely associated with the risk of stroke,” the researchers concluded.

Cognitive abilities decline more rapidly at the end of life than before the terminal period, and late-life participation in mentally stimulating activities might enhance cognitive functioning, according to two studies published in the online April 4 Neurology. In one study, 174 persons without dementia completed a battery of cognitive performance tests at annual intervals for six to 15 years prior to death, after which researchers assessed participants’ brains for evidence of Alzheimer’s disease. Although cognitive decline prior to the terminal period was relatively gradual, cognition declined rapidly during the terminal period. In the second study, 1,076 dementia-free older persons annually completed clinical evaluations (mean, 4.9 years) regarding cognitive performance as well as participation in mentally stimulating activities. Investigators found that cognitive activity participation and cognitive functioning declined at moderately correlative rates. “The results suggest that more frequent mental stimulation in old age leads to better cognitive functioning,” the researchers stated.

Patients with chronic temporal lobe epilepsy have extensive brain abnormalities and age-accelerated ventricular expansion that may have a significant neurodevelopmental impact, according to research published in the online April 3 Epilepsia. Investigators compared differences in brain structure as well as patterns of age-related change in 55 patients with chronic temporal lobe epilepsy with childhood or adolescent onset and 53 healthy controls. Using MRI studies, the researchers identified extensive anatomic abnormalities in patients with chronic temporal lobe epilepsy. Furthermore, participants with epilepsy showed age-accelerated changes in the third and lateral ventricles, though age-related changes in other regions of interest were mostly comparable with those of controls. “These cumulative structural abnormalities appear to represent a significant anatomic burden for persons with epilepsy, the consequences of which remain to be determined as they progress into elder years,” the study authors said.

Treatment with omega-3 fatty acid supplements is not correlated with reduction in disease activity in patients with relapsing-remitting multiple sclerosis (MS), according to a study published in the online April 16 issue of Archives of Neurology. From 2004 to 2008, investigators conducted a multicenter, randomized, double-blind, placebo-controlled clinical trial of 96 patients ages 18 to 55 with active relapsing-remitting MS. Half the participants were randomized to placebo, half were randomized to receive omega-3 fatty acids, and, after six months of treatment, all patients received 44 µg of interferon beta-1a three times per week for another 18 months. Results showed that MRI measurements of gadolinium-enhancing lesions were similar among groups in the first six months, and no difference in relapse rate was found after six or 24 months.

Patients with Parkinson’s disease often have persistent ocular tremors that prevent eye stability during fixation, which suggests that modern, precise oculomotor testing of this feature could serve as a biomarker for early diagnosis of Parkinson’s disease, researchers reported in the online April 9 Archives of Neurology. The investigators conducted a case-control study with 112 patients with Parkinson’s disease, 18 de novo, untreated patients, and 60 age-matched controls. Patients’ oculomotor parameters were assessed with precise eye-tracking technology, and oculomotor function between groups during fixation was compared with oculomotor function while tracking a randomly displaced target on a computer monitor. All 112 patients with Parkinson’s disease showed oscillatory fixation instability. “The pervasiveness and specificity of [ocular tremor] suggest that modern, precise oculomotor testing could provide a valuable early physiological biomarker for diagnosing Parkinson’s disease,” the study authors concluded.

Wrist-worn biosensors that continuously record the sympathetically mediated electrodermal activity (EDA) of patients with epilepsy show autonomic correlates of postictal EEG suppression that may serve as biomarkers for risk of sudden death in epilepsy, according to research published in the online April 25 Neurology. Researchers recorded a total of 34 seizures (22 complex partial; 12 tonic-clonic) in patients with refractory epilepsy who wore the wrist sensors. Analysis of the postictal period showed heightened heart rate and a surge in EDA at the same time as persistent suppression of parasympathetic-modulated high-frequency (HF) power of heart rate. In addition, increased EDA response amplitude was associated with increased duration of EEG suppression (r = 0.81), and decreased HF power was associated with increased duration of EEG suppression (r = -0.87). “The magnitude of both sympathetic activation and parasympathetic suppression increases with duration of EEG suppression after tonic-clonic seizures,” the investigators stated.

The suggested immobilization test (SIT) may assist clinicians in diagnosing restless legs syndrome (RLS) in patients with Parkinson’s disease, according to research published in the March 21 online Movement Disorders. The investigators compared SIT scores and polysomnography measures of 50 patients with Parkinson’s disease (25 with RLS), 25 patients with primary RLS, and 25 controls matched for age and sex. Results indicated that patients with Parkinson’s disease and RLS had increased mean leg discomfort scores and high leg discomfort at the end of the test compared with patients with Parkinson’s disease but without RLS. In addition, the SIT showed sensitivity of 91% and specificity of 72% for RLS diagnosis in patients with Parkinson’s disease during symptomatic time intervals. “The sensory SIT is a simple test that may help diagnose RLS in patients with Parkinson’s disease,” the researchers concluded. 

Adults with a higher level of daily physical activity may have a decreased risk of Alzheimer’s disease, according to research published in the online April 18 Neurology. Researchers objectively measured the continuous exercise and nonexercise physical activity of 716 older subjects without dementia by using actigraphy monitoring for up to 10 days. During an average follow-up of four years, 71 persons were diagnosed with clinical Alzheimer’s disease, and the investigators identified an inverse association between total daily physical activity and Alzheimer’s disease (hazard ratio, 0.477) after adjusting for age, sex, and education. This association remained following further adjustments for self-reported physical, social, and cognitive activities; APOE allele status; and current level of motor function, depressive symptoms, and chronic health conditions. “A higher level of total daily physical activity is associated with reduced risk of Alzheimer’s disease,” the investigators concluded.

The herpes zoster vaccine is associated with a small increased risk of allergic reactions in the week following vaccination but is generally safe and well tolerated, according to a study published in the May Journal of Internal Medicine. Researchers analyzed data from 193,083 persons ages 50 and older who had received a zoster vaccine from January 2007 to December 2008 and who were included in the Vaccine Safety Datalink project. A case-centered approach and a self-controlled case series approach were used for analysis. Although results showed that risk of allergic reaction significantly increased within one to seven days of vaccination (RR, 2.13), the investigators identified no increased risk for cerebrovascular or cardiovascular events, meningitis, encephalitis, encephalopathy, Ramsay–Hunt syndrome, or Bell’s palsy. According to the study authors, this research supports the safety results from the zoster vaccine’s prelicensure clinical trials.

Consumption of low-fat dairy products may reduce the risk of stroke, according to research published in the online April 19 Stroke. In a prospective cohort study, researchers followed 74,961 Swedish women and men who were free from cancer and cardiovascular disease. During a mean 10.2-year follow-up, 4,089 cases of stroke were recorded among the cohort, including 3,159 cerebral infarctions, 583 hemorrhagic strokes, and 347 unspecified strokes. Analysis showed an inverse association between consumption of low-fat dairy food and risk of total stroke and cerebral infarction, with multivariable relative risks for the highest compared with the lowest quintile of low-fat dairy consumption of .88 for total stroke and .87 for cerebral infarction. “These results suggest that low-fat dairy consumption is inversely associated with the risk of stroke,” the researchers concluded.

Cognitive abilities decline more rapidly at the end of life than before the terminal period, and late-life participation in mentally stimulating activities might enhance cognitive functioning, according to two studies published in the online April 4 Neurology. In one study, 174 persons without dementia completed a battery of cognitive performance tests at annual intervals for six to 15 years prior to death, after which researchers assessed participants’ brains for evidence of Alzheimer’s disease. Although cognitive decline prior to the terminal period was relatively gradual, cognition declined rapidly during the terminal period. In the second study, 1,076 dementia-free older persons annually completed clinical evaluations (mean, 4.9 years) regarding cognitive performance as well as participation in mentally stimulating activities. Investigators found that cognitive activity participation and cognitive functioning declined at moderately correlative rates. “The results suggest that more frequent mental stimulation in old age leads to better cognitive functioning,” the researchers stated.

Patients with chronic temporal lobe epilepsy have extensive brain abnormalities and age-accelerated ventricular expansion that may have a significant neurodevelopmental impact, according to research published in the online April 3 Epilepsia. Investigators compared differences in brain structure as well as patterns of age-related change in 55 patients with chronic temporal lobe epilepsy with childhood or adolescent onset and 53 healthy controls. Using MRI studies, the researchers identified extensive anatomic abnormalities in patients with chronic temporal lobe epilepsy. Furthermore, participants with epilepsy showed age-accelerated changes in the third and lateral ventricles, though age-related changes in other regions of interest were mostly comparable with those of controls. “These cumulative structural abnormalities appear to represent a significant anatomic burden for persons with epilepsy, the consequences of which remain to be determined as they progress into elder years,” the study authors said.

Treatment with omega-3 fatty acid supplements is not correlated with reduction in disease activity in patients with relapsing-remitting multiple sclerosis (MS), according to a study published in the online April 16 issue of Archives of Neurology. From 2004 to 2008, investigators conducted a multicenter, randomized, double-blind, placebo-controlled clinical trial of 96 patients ages 18 to 55 with active relapsing-remitting MS. Half the participants were randomized to placebo, half were randomized to receive omega-3 fatty acids, and, after six months of treatment, all patients received 44 µg of interferon beta-1a three times per week for another 18 months. Results showed that MRI measurements of gadolinium-enhancing lesions were similar among groups in the first six months, and no difference in relapse rate was found after six or 24 months.

Patients with Parkinson’s disease often have persistent ocular tremors that prevent eye stability during fixation, which suggests that modern, precise oculomotor testing of this feature could serve as a biomarker for early diagnosis of Parkinson’s disease, researchers reported in the online April 9 Archives of Neurology. The investigators conducted a case-control study with 112 patients with Parkinson’s disease, 18 de novo, untreated patients, and 60 age-matched controls. Patients’ oculomotor parameters were assessed with precise eye-tracking technology, and oculomotor function between groups during fixation was compared with oculomotor function while tracking a randomly displaced target on a computer monitor. All 112 patients with Parkinson’s disease showed oscillatory fixation instability. “The pervasiveness and specificity of [ocular tremor] suggest that modern, precise oculomotor testing could provide a valuable early physiological biomarker for diagnosing Parkinson’s disease,” the study authors concluded.

Wrist-worn biosensors that continuously record the sympathetically mediated electrodermal activity (EDA) of patients with epilepsy show autonomic correlates of postictal EEG suppression that may serve as biomarkers for risk of sudden death in epilepsy, according to research published in the online April 25 Neurology. Researchers recorded a total of 34 seizures (22 complex partial; 12 tonic-clonic) in patients with refractory epilepsy who wore the wrist sensors. Analysis of the postictal period showed heightened heart rate and a surge in EDA at the same time as persistent suppression of parasympathetic-modulated high-frequency (HF) power of heart rate. In addition, increased EDA response amplitude was associated with increased duration of EEG suppression (r = 0.81), and decreased HF power was associated with increased duration of EEG suppression (r = -0.87). “The magnitude of both sympathetic activation and parasympathetic suppression increases with duration of EEG suppression after tonic-clonic seizures,” the investigators stated.

The suggested immobilization test (SIT) may assist clinicians in diagnosing restless legs syndrome (RLS) in patients with Parkinson’s disease, according to research published in the March 21 online Movement Disorders. The investigators compared SIT scores and polysomnography measures of 50 patients with Parkinson’s disease (25 with RLS), 25 patients with primary RLS, and 25 controls matched for age and sex. Results indicated that patients with Parkinson’s disease and RLS had increased mean leg discomfort scores and high leg discomfort at the end of the test compared with patients with Parkinson’s disease but without RLS. In addition, the SIT showed sensitivity of 91% and specificity of 72% for RLS diagnosis in patients with Parkinson’s disease during symptomatic time intervals. “The sensory SIT is a simple test that may help diagnose RLS in patients with Parkinson’s disease,” the researchers concluded. 

Adults with a higher level of daily physical activity may have a decreased risk of Alzheimer’s disease, according to research published in the online April 18 Neurology. Researchers objectively measured the continuous exercise and nonexercise physical activity of 716 older subjects without dementia by using actigraphy monitoring for up to 10 days. During an average follow-up of four years, 71 persons were diagnosed with clinical Alzheimer’s disease, and the investigators identified an inverse association between total daily physical activity and Alzheimer’s disease (hazard ratio, 0.477) after adjusting for age, sex, and education. This association remained following further adjustments for self-reported physical, social, and cognitive activities; APOE allele status; and current level of motor function, depressive symptoms, and chronic health conditions. “A higher level of total daily physical activity is associated with reduced risk of Alzheimer’s disease,” the investigators concluded.

The herpes zoster vaccine is associated with a small increased risk of allergic reactions in the week following vaccination but is generally safe and well tolerated, according to a study published in the May Journal of Internal Medicine. Researchers analyzed data from 193,083 persons ages 50 and older who had received a zoster vaccine from January 2007 to December 2008 and who were included in the Vaccine Safety Datalink project. A case-centered approach and a self-controlled case series approach were used for analysis. Although results showed that risk of allergic reaction significantly increased within one to seven days of vaccination (RR, 2.13), the investigators identified no increased risk for cerebrovascular or cardiovascular events, meningitis, encephalitis, encephalopathy, Ramsay–Hunt syndrome, or Bell’s palsy. According to the study authors, this research supports the safety results from the zoster vaccine’s prelicensure clinical trials.

Consumption of low-fat dairy products may reduce the risk of stroke, according to research published in the online April 19 Stroke. In a prospective cohort study, researchers followed 74,961 Swedish women and men who were free from cancer and cardiovascular disease. During a mean 10.2-year follow-up, 4,089 cases of stroke were recorded among the cohort, including 3,159 cerebral infarctions, 583 hemorrhagic strokes, and 347 unspecified strokes. Analysis showed an inverse association between consumption of low-fat dairy food and risk of total stroke and cerebral infarction, with multivariable relative risks for the highest compared with the lowest quintile of low-fat dairy consumption of .88 for total stroke and .87 for cerebral infarction. “These results suggest that low-fat dairy consumption is inversely associated with the risk of stroke,” the researchers concluded.

Cognitive abilities decline more rapidly at the end of life than before the terminal period, and late-life participation in mentally stimulating activities might enhance cognitive functioning, according to two studies published in the online April 4 Neurology. In one study, 174 persons without dementia completed a battery of cognitive performance tests at annual intervals for six to 15 years prior to death, after which researchers assessed participants’ brains for evidence of Alzheimer’s disease. Although cognitive decline prior to the terminal period was relatively gradual, cognition declined rapidly during the terminal period. In the second study, 1,076 dementia-free older persons annually completed clinical evaluations (mean, 4.9 years) regarding cognitive performance as well as participation in mentally stimulating activities. Investigators found that cognitive activity participation and cognitive functioning declined at moderately correlative rates. “The results suggest that more frequent mental stimulation in old age leads to better cognitive functioning,” the researchers stated.

Patients with chronic temporal lobe epilepsy have extensive brain abnormalities and age-accelerated ventricular expansion that may have a significant neurodevelopmental impact, according to research published in the online April 3 Epilepsia. Investigators compared differences in brain structure as well as patterns of age-related change in 55 patients with chronic temporal lobe epilepsy with childhood or adolescent onset and 53 healthy controls. Using MRI studies, the researchers identified extensive anatomic abnormalities in patients with chronic temporal lobe epilepsy. Furthermore, participants with epilepsy showed age-accelerated changes in the third and lateral ventricles, though age-related changes in other regions of interest were mostly comparable with those of controls. “These cumulative structural abnormalities appear to represent a significant anatomic burden for persons with epilepsy, the consequences of which remain to be determined as they progress into elder years,” the study authors said.

Treatment with omega-3 fatty acid supplements is not correlated with reduction in disease activity in patients with relapsing-remitting multiple sclerosis (MS), according to a study published in the online April 16 issue of Archives of Neurology. From 2004 to 2008, investigators conducted a multicenter, randomized, double-blind, placebo-controlled clinical trial of 96 patients ages 18 to 55 with active relapsing-remitting MS. Half the participants were randomized to placebo, half were randomized to receive omega-3 fatty acids, and, after six months of treatment, all patients received 44 µg of interferon beta-1a three times per week for another 18 months. Results showed that MRI measurements of gadolinium-enhancing lesions were similar among groups in the first six months, and no difference in relapse rate was found after six or 24 months.

Patients with Parkinson’s disease often have persistent ocular tremors that prevent eye stability during fixation, which suggests that modern, precise oculomotor testing of this feature could serve as a biomarker for early diagnosis of Parkinson’s disease, researchers reported in the online April 9 Archives of Neurology. The investigators conducted a case-control study with 112 patients with Parkinson’s disease, 18 de novo, untreated patients, and 60 age-matched controls. Patients’ oculomotor parameters were assessed with precise eye-tracking technology, and oculomotor function between groups during fixation was compared with oculomotor function while tracking a randomly displaced target on a computer monitor. All 112 patients with Parkinson’s disease showed oscillatory fixation instability. “The pervasiveness and specificity of [ocular tremor] suggest that modern, precise oculomotor testing could provide a valuable early physiological biomarker for diagnosing Parkinson’s disease,” the study authors concluded.

Wrist-worn biosensors that continuously record the sympathetically mediated electrodermal activity (EDA) of patients with epilepsy show autonomic correlates of postictal EEG suppression that may serve as biomarkers for risk of sudden death in epilepsy, according to research published in the online April 25 Neurology. Researchers recorded a total of 34 seizures (22 complex partial; 12 tonic-clonic) in patients with refractory epilepsy who wore the wrist sensors. Analysis of the postictal period showed heightened heart rate and a surge in EDA at the same time as persistent suppression of parasympathetic-modulated high-frequency (HF) power of heart rate. In addition, increased EDA response amplitude was associated with increased duration of EEG suppression (r = 0.81), and decreased HF power was associated with increased duration of EEG suppression (r = -0.87). “The magnitude of both sympathetic activation and parasympathetic suppression increases with duration of EEG suppression after tonic-clonic seizures,” the investigators stated.

The suggested immobilization test (SIT) may assist clinicians in diagnosing restless legs syndrome (RLS) in patients with Parkinson’s disease, according to research published in the March 21 online Movement Disorders. The investigators compared SIT scores and polysomnography measures of 50 patients with Parkinson’s disease (25 with RLS), 25 patients with primary RLS, and 25 controls matched for age and sex. Results indicated that patients with Parkinson’s disease and RLS had increased mean leg discomfort scores and high leg discomfort at the end of the test compared with patients with Parkinson’s disease but without RLS. In addition, the SIT showed sensitivity of 91% and specificity of 72% for RLS diagnosis in patients with Parkinson’s disease during symptomatic time intervals. “The sensory SIT is a simple test that may help diagnose RLS in patients with Parkinson’s disease,” the researchers concluded.