News Roundup: New and Noteworthy Information
Both higher overall and abdominal adiposity are associated with an increased risk for restless legs syndrome (RLS), researchers reported in the April 7 Neurology. A total of 65,554 women and 23,119 men without diabetes, arthritis, and pregnancy were included in the analysis. Participants were considered to have RLS if they experienced restless legs five or more times a month and met four diagnostic criteria per the International RLS Study Group. RLS was diagnosed in 6.4% of the women and in 4.1% of the men. Multivariate adjusted odds ratios for RLS were 1.42 for participants with a BMI greater than 30 versus less than 23 and 1.60 for highest versus lowest waist circumference quintiles. “Greater BMI in early adulthood and weight gain were also associated with a higher prevalence of RLS,” stated the investigators.
In utero exposure to valproate is associated with an increased risk of impaired cognitive function at age 3, according to a study in the online April 16 New England Journal of Medicine. Researchers compared neurodevelopmental outcomes at age 3 in 309 children exposed to various antiepileptic drugs. “At three years of age, children who had been exposed to valproate in utero had significantly lower IQ scores than those who had been exposed to other antiepileptic drugs,” the authors stated. IQ scores for children exposed to valproate were, on average, nine points lower than those exposed to lamotrigine, seven points lower than those exposed to phenytoin, and six points lower than those exposed to carbamazepine. “This finding supports a recommendation that valproate not be used as the first-choice drug in women of childbearing potential,” the investigators concluded.
Older patients with type 2 diabetes and a history of severe hypoglycemic episodes have a greater risk of dementia, per a report in the April 15 JAMA. Researchers collected data on hypoglycemic events that occurred between 1980 and 2002; patients with no prior diagnosis of dementia, mild cognitive impairment, or general memory complaints were followed up through January 15, 2007, for dementia diagnosis. “At least one episode of hypoglycemia was diagnosed in 1,465 patients (8.8%), and dementia was diagnosed in 1,822 patients (11%) during follow-up; 250 patients had both dementia and at least one episode of hypoglycemia (16.95%),” the investigators stated. Compared with patients without hypoglycemia, patients with single or multiple episodes of hypoglycemia had a graded increase in risk, with fully adjusted hazard ratios of 1.26, 1.80, and 1.94 for one, two, and three or more episodes, respectively.
Certain Parkinson’s disease drugs have pathologic syndrome–inducing effects that can be mistaken for primary psychotic disease, according to a report in the April Mayo Clinic Proceedings. Researchers retrospectively reviewed the medical records of 267 patients with Parkinson’s disease. The main outcome measure was compulsive gambling or hypersexuality developing after parkinsonism onset, including the temporal relationship to Parkinson’s disease drug use. Sixty-six patients (10.6%) were taking a dopamine agonist; of these, seven (2.6%) met the main outcome measure. All seven patients were also among a group of 38 patients taking therapeutic doses > 2 mg pramipexole or 6 mg ropinirole daily). “Behaviors were clearly pathologic and disabling in five: 7.6% of all patients taking an agonist and 13.2% of those taking therapeutic doses,” the investigators noted.
Children with prenatal methamphetamine exposure have altered white matter maturation, researchers reported in the April 15 online Neurology. Twenty-nine methamphetamine-exposed children and 37 unexposed children (ages 3 to 4) underwent 12-direction diffusion tensor imaging on a 3-Tesla MRI scanner. Children with prenatal methamphetamine exposure had lower apparent diffusion coefficient in the frontal (right, -2.1%; left, -2.0%) and parietal white matter (right, -3.9%; left, -3.3%). In addition, methamphetamine-exposed children showed a trend for higher fractional anisotropy in left frontal white matter (+ 4.9%). “Since less myelination and higher dendritic or spine density have been reported in animals exposed to methamphetamine, lower diffusion in our children may reflect more compact axons or greater dendritic or spine density associated with prenatal methamphetamine exposure,” investigators commented.
Use of transcranial Doppler (TCD) ultrasonography screening to help prevent stroke in children with sickle cell disease increased sixfold, according to a study in the April 14Neurology. Prior to 1998, the average annual rate of TCD screening in 157 children with sickle cell disease was 1.8 per 100 person-years. From 1998 through 1999, that rate increased to 5.0. From 2000 through 2005, the rate increased to 11.4. Physical proximity to the vascular laboratory was the only independent predictor of screening. “The annualized stroke rate pre-TCD was 0.44 per 100 person-years, compared to 0.19 post TCD,” investigators stated. “Increased availability of TCD screening could improve the utilization of this effective primary stroke prevention strategy.”
