Individuals with 22q11.1DS don’t sleep well, new research suggests.
Sleep-related brain activity patterns serve as a biomarker to identifying the start of neuropsychiatric illnesses in patients with Deletion Syndrome (or DiGeorge Syndrome) represented by the sequence 22q11.2DS, a genetic abnormality. Many children with this syndrome have developmental delays. For instance, they may have delays in speech development as well as growth. They may also have learning or intellectual disabilities. Executive functioning skills, including reading and performing mathematical tasks are difficult.
One in three thousand births result in 22q11.2DS and include a gene loss of about 30 genes on chromosome 22. The syndrome increases the likelihood of autism spectrum disorder (ASD), epileptic seizures, and attention-deficit hyperactivity disorder ADHD). Additionally, it ranks highly among the biological risk factors for schizophrenia. Conditions including poor circulation, frequent infections, delayed growth, breathing problems and poor muscle tone, among other issues, might also be present. Unfortunately, little information is available about the molecular processes that trigger the symptoms of 22q11.2DS.
According to a recent study, people with Deletion Syndrome experience significant sleep pattern changes, including more N3 NREM sleep. The study also revealed that young people with the genetic mutation are more likely to have psychiatric illnesses while sleeping. Research findings reveal that most young individuals with Deletion Syndrome, in general, have sleep issues. These issues mainly include insomnia and sleep fragmentation, both of which are associated with mental health disorders.
“We have recently shown that the majority of young people with 22q11.2DS have sleep problems, particularly insomnia and sleep fragmentation, that are linked with psychiatric disorders,” explained co-senior author Marianne van den Bree, Professor of Psychological Medicine at Cardiff University, UK.
People with mental illnesses may not always appear sick, especially if their condition is moderate. Other people might exhibit more overt symptoms, including disorientation, agitation, or withdrawal. However, each sickness remarkably impacts a person’s thoughts, feelings, and behaviors. An electroencephalogram is a recognized method of assessing brain activity during sleep (EEG) that keeps track of the electrical activity during sleep to identify slow-wave and spindle oscillation patterns. These characteristics of non-rapid eye movement (NREM) support brain and memory development.
Nick Donnelly, the lead author of the study and a Clinical Lecturer in General Adult Psychiatry at the University of Bristol, UK, believes that the properties and coordination of brain alterations serve as biomarkers for psychiatric disorders. That’s because sleep EEG alters many neurodevelopmental disorders.
“Because sleep EEG is known to be altered in many neurodevelopmental disorders, the properties and coordination of these alterations can be used as biomarkers for psychiatric dysfunction” said Donnelly.
In order to study the same in 22q11.2DS, the research team took a place at 28 children between ages 6 and 20, with chromosome deletion as well as 17 unaffected siblings. The study found that, compared to their siblings, the group with 22q11.2DS exhibited differences in sleep, with abnormal cycles of N1, N3 NREM sleep and rapid eye movement (REM) sleep.
Additionally, those with the chromosomal deletion had higher spindle EEG power and slow-wave oscillation. There was a close link between the spindle and slow-wave EEG features and growth in the density and frequency of spindle patterns in the 22q112.DS group. The brain areas that produce these oscillations may have changed because of these modifications.
Together, the EEG results paint a nuanced image of the neurophysiology of sleep in individuals with 22q11.2DS and point out variations that might be used as biomarkers for neurodevelopmental disorders linked to 22q11.2DS.