Children with insomnia may have impaired heart rate variability

Mar 02, 2010

Children with insomnia and shorter sleep duration had impaired modulation of heart rhythm during sleep, Pennsylvania researchers reported at the American Heart Association's 50th Annual Conference on Cardiovascular Disease Epidemiology and Prevention.

In a study of young children, researchers showed that insomnia symptoms were consistently associated with impaired heart variability measures. They also found a significant but less consistent pattern with shortened sleep duration and decreased variability.

Heart rate variability is the beat-to-beat variations of heart rate. In a healthy person, beat-to-beat intervals change slightly in response to automatic functions like breathing.

The study included 612 elementary school children in the first to fifth grades. The children were average age 9, and 25 percent were non-white and 49 percent were boys. All were generally in good health. Their parents completed the Pediatric Behavior Scale, including two questions that focused on symptoms of insomnia.

Researchers examined the children overnight in a sleep laboratory with polysomnography (PSG), a standardized method for measuring . The researchers measured sleep duration, trouble falling asleep, the number of wake-ups and problems going back to sleep if awakened. They also measured cardiac autonomic modulation (CAM), the balance of the sympathetic and the parasympathetic control of the heart rate rhythm.

A balance is needed between the sympathetic modulation that "excites" the heart and the parasympathetic modulation that "calms" the heart, said Mr. Fan He, the lead-author of the study and a graduate student at Penn State University College of Medicine in Hershey, Pa. "The balance between the sympathetic and the parasympathetic provides a favorable profile for the heart."

The study showed:

  • Children with reported insomnia had impaired CAM with a shift towards more sympathetic or excitable activation of the heart rhythm. There was a 3 percent to 5 percent reduction in the parasympathetic modulation of heart rhythm in children with insomnia.
  • Children with longer sleep duration had a slower heart rate indicative of a balance of heart rhythm, with a shift towards more parasympathetic modulation. The heart rate of children who slept eight hours was two beats per minute slower than that of kids who slept only seven hours.
  • Insomnia and short , even in young children, resulted in a physiological activation of the sympathetic modulation.
"Kids who sleep a longer duration have a healthier heart regulation profile compared to kids who sleep shorter durations," said Duanping Liao, M.D., Ph.D., co-author of the study and professor of epidemiology at Penn State University College of Medicine in Hershey, Pa. "Their hearts are more excitable if they have insomnia. If the heart is too excited, that means it is beating too fast and usually that isn't good. These data indicate that among young children with symptoms reported by their parents, there already is an impairment of cardiovascular autonomic regulation, long before they reach the traditional high-risk period for cardiovascular disease."

Parents should encourage their children to have healthy bedtime habits that encourage sleep, Liao said. "Watching television before going to bed and waking up to return text messages are examples of activities that could have a harmful affect on healthy sleep patterns in children."

Liao called for further studies in to determine the impact of sleep deprivation and stress and the possible long-term risk of cardiovascular disease and obesity. "Previous studies have shown a strong association of heart rhythm regulation and heart risk in adults. It's quite possible that this kind of stress can have a long-term impact even at a young age."

The study was funded by the National Heart, Lung, and Blood Institute.

Explore further: Medicare hospital fund to last 4 years longer

add to favorites email to friend print save as pdf

Related Stories

Sleep restriction reduces heart rate variability

Jun 13, 2007

Chronic sleep restriction has a negative effect on a person's cardiac activity, which may elevate the risk of cardiovascular disease and mortality, according to a research abstract that will be presented Wednesday at SLEEP ...

Respiratory rhythms can help predict insomnia

Oct 20, 2008

The breathing and heart rates and cortisol levels of women with metastatic breast cancer can be used to predict if they'll suffer from chronic insomnia and sleep disruptions, a common complaint from patients who want to maintain ...

Recommended for you

Preterm children's brains can catch up years later

2 hours ago

There's some good news for parents of preterm babies – latest research from the University of Adelaide shows that by the time they become teenagers, the brains of many preterm children can perform almost as well as those ...

Mortality rates increase due to extreme heat and cold

2 hours ago

Epidemiological studies have repeatedly shown that death rates rise in association with extremely hot weather. The heat wave in Western Europe in the summer of 2003, for example, resulted in about 22,000 extra deaths. A team ...

It takes more than practice to excel, psychologist reports

3 hours ago

Case Western Reserve University's new assistant professor of psychology Brooke N. Macnamara, PhD, and colleagues have overturned a 20-year-old theory that people who excel in their fields are those who practiced the most.

User comments : 0