One in Three Children with Multiple Sclerosis has Cognitive Impairment

Data from the largest multicenter study accessing cognitive functioning in children with multiple sclerosis (MS) reveals that one-third of these patients have cognitive impairment, according to a research paper published in the Journal of Child Neurology. Led by Lauren B. Krupp, MD, Director of the Lourie Center for Pediatric Multiple Sclerosis at Stony Brook Long Island Children’s Hospital, the study indicates that patients experience a range of problems related to cognition.

In “Cognitive Impairment Occurs in Children and Adolescents with Multiple Sclerosis: Results from a United States Network,” Dr. Krupp and colleagues from Stony Brook and five other national Pediatric MS Centers of Excellence measured the cognitive functioning of 187 children and adolescents with MS, and 44 who experienced their first neurologic episode (clinically isolated syndrome) indicative of MS. They found that 35 percent of the patients with MS and 18 percent of those with clinically isolated syndrome met criteria for cognitive impairment. All patients were under age 18 with an average disease duration of about two years. 

“This study is important because it represents the largest study to date to apply a comprehensive neuropsychological battery of tests to evaluate the cognitive functioning of children with MS, and the results clearly show us that cognitive issues are widespread and can occur early on in the disease course of these patients,” said Dr. Krupp, also a Professor of Neurology at Stony Brook University School of Medicine. “These are critically important findings that emphasize the need for prompt recognition of our patients’ cognitive problems and for neurologists and other MS specialists to discover ways to intervene and help improve the cognitive abilities of these children while they are in school and beyond.”

Can Going Hungry As a Child Slow Down Cognitive Decline in Later Years?

People who sometimes went hungry as children had slower cognitive decline once they were elderly than people who always had enough food to eat, according to a new study published in the December 11, 2012, print issue of Neurology®, the medical journal of the American Academy of Neurology.

“These results were unexpected because other studies have shown that people who experience adversity as children are more likely to have problems such as heart disease, mental illness and even lower cognitive functioning than people whose childhoods are free of adversity,” said study author Lisa L. Barnes, PhD, of Rush University Medical Center in Chicago.

For the African American participants, the 5.8 percent who reported that they went without enough food to eat sometimes, often or always were more likely to have a slower rate of cognitive decline, or decline that was reduced by about one-third, than those who rarely or never went without enough food to eat. The 8.4 percent of African American participants who reported that they were much thinner at age 12 than other kids their age also were more likely to have a slower rate of cognitive decline, also by one-third, than those who said they were about the same size or heavier than other kids their age. For Caucasians, there was no relationship between any of the childhood adversity factors and cognitive decline. Barnes said researchers aren’t sure why childhood hunger could have a possible protective effect on cognitive decline. One potential explanation for the finding could be found in research that has shown that calorie restriction can delay the onset of age-related changes in the body and increase the life span. Another explanation could be a selective survival effect. The older people in the study who experienced childhood adversity may be the hardiest and most resilient of their era; those with the most extreme adversity may have died before they reached old age.

Barnes noted that the results stayed the same after researchers adjusted for factors such as amount of education and health problems. The results also did not change after researchers repeated the analysis after excluding people with the lowest cognitive function at the beginning of the study to help rule out the possibility that people with mild, undiagnosed Alzheimer’s disease were included in the study.

Because relatively few Caucasians in the study reported childhood adversity, the study may not have been able to detect an effect of adversity on cognitive decline in Caucasians, Barnes said.

Two heads are better than one

Dramatic expansion of the human cerebral cortex, over the course of evolution, accommodated new areas for specialized cognitive function, including language. Understanding the genetic mechanisms underlying these changes, however, remains a challenge to neuroscientists.

A team of researchers in Japan, led by Hideyuki Okano of Keio University School of Medicine and Tomomi Shimogori of the RIKEN Brain Science Institute, has now elucidated the mechanisms of cortical evolution. They used molecular techniques to compare the gene expression patterns in mouse and monkey brains. 

Using the technique called in situ hybridization to visualize the distribution of mRNA transcripts, Okano, Shimogori and their colleagues examined the expression patterns of genes that are known to regulate development of the mouse brain. They compared these patterns to those of the same genes in the brain of the common marmoset. They found that most of the genes had similar expression patterns in mice and marmosets, but that some had strikingly different patterns between the two species. Notably, some areas of the visual and prefrontal cortices showed expression patterns that were unique to marmosets. 

The researchers also found differences in gene expression within regions that connect the prefrontal cortex and hippocampus, a structure that is critical for learning and memory.