Researchers from Johns Hopkins Children’s Centre have found that children suffering from Attention Deficit Hyperactivity Disorder (ADHD) have a higher possibility of having Loss Of Control Eating Syndrome (LOC-ES).
Although the children with ADHD lose weight because of stimulant drugs, the disorder is usually associated with obesity, study leader Shauna P Reinblatt, assistant professor in the Division of Child and Adolescent Psychiatry at the Johns Hopkins University School of Medicine, said.
The obesity in children with ADHD is being attributed to a link between the hallmark impulsivity of ADHD and loss of control over appetite and food consumption.
The study included 79 children between the ages of 8 to 14 from Baltimore area. Researchers based their relation between ADHD and LOC-ES on interviews, parental reports and objective measures. The children also underwent neuropsychological testing to measure how well they were able to control their impulses.
The study found that the chances of LOC-ES in children suffering from ADHD were increased 12 times as compared to those without ADHD. On the other hand, children suffering from LOC-ES were at a risk of having ADHD 7 times higher than others.
It was also found that the children with ADHD suffering from LOC-ES have a more severe form of ADHD streaked by more impulsive behavior that particularly manifests in their eating patterns, Dr. Reinblatt said.
While obesity is primarily associated with weight gain, a new study suggests it triggers inflammation in the nervous system that could damage important regions of the brain.
Developments in MRI, like diffusion tensor imaging (DTI), a technique that tracks the diffusion of water along the brain’s signal-carrying white matter tracts, have enabled researchers to study this damage directly.
“Brain changes were found in obese adolescents related to regions responsible for control of appetite, emotions and cognitive functions,” said study co-author Pamela Bertolazzi from the University of Sao Paulo in Brazil.
The World Health Organisation (WHO) data indicates the number of overweight or obese infants and young children increased from 32 million in 1990 to 41 million in 2016 globally.
For the study, researchers compared DTI results in 59 obese and 61 healthy adolescents, aged 12-16 years.
From DTI, the researchers derived a measure called fractional anisotropy (FA), which correlates with the condition of the brain’s white matter. A reduction in fractional anisotropy is indicative of increasing damage in the white matter.
The results showed reduction of FA values in the obese adolescents in regions located in the corpus callosum, a bundle of nerve fibre that connects the left and right hemispheres of the brain.
Decrease of fractional anisotropy was also found in the middle orbitofrontal gyrus, a brain region related to emotional control and the reward circuit. None of the brain regions in obese patients had increased fractional anisotropy.
According to researchers, this pattern of damage correlated with some inflammatory markers, like leptin, a hormone made by fat cells that helps regulate energy and fat stores.
In some obese people, the brain doesn’t respond to leptin, causing them to keep eating despite adequate or excessive fat stores. This condition, known as leptin resistance, makes the fat cells produce even more leptin.
Worsening condition of the white matter was also associated with levels of insulin, a hormone produced in the pancreas that helps regulate blood sugar levels. Obese people often suffer from insulin resistance.
“Our maps showed a positive correlation between brain changes and hormones, such as leptin and insulin,” Bertolazzi said.