November 6, 2007

Vanderbilt study links melatonin excretion with sleep levels in children with autism; Children with deeper levels of sleep have higher levels of melatonin

Vanderbilt sleep researchers are reporting a relationship between good sleep and how much melatonin the body produces ñ the first in a series of research studies intended to help children with autism spectrum disorders sleep through the night.

Vanderbilt sleep researchers are reporting a relationship between good sleep and how much melatonin the body produces – the first in a series of research studies intended to help children with autism spectrum disorders sleep through the night.

More research is needed before recommending that the medication-free children studied begin taking over-the-counter and inexpensive melatonin supplements to benefit their sleep patterns. But initial findings are promising, according to lead author Beth Malow, M.D., director of the Vanderbilt Sleep Disorders Center.

Malow presented results of the study “Nocturnal urine 6-sulfatoxymelatonin levels are related to sleep parameters in children with autism,” Nov. 3 at the annual meeting of the Society for Neuroscience in San Diego.

“This suggests that children with ASD who have decreased melatonin levels have decreased levels of deep sleep,” Malow said. “We didn’t actually give the supplement, we measured natural levels of melatonin in the body. One could infer, based on what we found, that a supplement might be good.”

“Rather than just giving melatonin to children with autism ‘willy nilly’ we want to have some scientific rationale for what we are doing and this study provides that scientific rationale because it is showing that there is a relationship between the amount of melatonin these children are naturally producing and sleep patterns.”

Melatonin affects sleep rhythms and brain development, and is released during sleep by the pineal gland of the brain. Low levels of melatonin have been reported in children with autism, although whether these levels are related to sleep problems has not been well studied.

The Vanderbilt melatonin study – which is the first to look at sleep parameters – examined 26 children with autism who were medication-free and without a history of epilepsy or mental retardation, and seven age-matched controls, studying the relationship between a by-product of melatonin found in the urine, urinary 6-sulfatoxymelatonin (6-SM), and the sleep structure of children with autism, ages 4-9 years.

Malow and her Department of Neurology colleagues Liya Beyderman and Emmanuel Botzolakis analyzed the overnight rate of 6-SM in the urine during two nights of sleep studies. Levels of 6-SM were compared with sleep study findings, which showed that children with higher levels of 6-SM had higher amounts of deep sleep, a portion of sleep involved in memory and growth.

The results support an emerging area of treatment – using melatonin supplements to improve sleep in children with autism spectrum disorders.

“In a nutshell there seems to be a relationship between the level of sleep you are getting and how much melatonin you produce,” Malow said.

“If you are not a good sleeper part of that could be due to not making sufficient melatonin and taking supplemental melatonin might help but obviously this is something that would have to be explored. Before we embark on a trial of supplemental melatonin for children with autism it is important to have some preliminary data on kids who sleep well or sleep poorly and what their melatonin level is like.”

It was also important to have very clear diagnosis of ASD in the children and to have “medication-free” participants, because melatonin can be affected by medication, she said.

Children with autism spectrum disorders frequently suffer from irregular sleep patterns that can result in a variety of sleep problems, including insomnia. Although there are many causes of these sleep problems, the natural hormone melatonin may play a role, Malow said.

Title: Nocturnal urine 6-sulfatoxymelatonin levels are related to sleep parameters in children with autism

Authors: *B. A. MALOW, L. BEYDERMAN, E. J. BOTZOLAKIS;

Dept Neurology, Vanderbilt Univ. Med. Ctr., Nashville, TN


Autism spectrum disorders are a group of brain conditions of unknown cause. They affect children from a young age and are characterized by difficulties with communication and social interaction, as well as restricted interests. The overall prevalence of autism is about 60 cases per 10,000 births, with males being three to four times more likely than females to be affected. They are thought to have a genetic component, though environmental factors may also play a role.

Media Contact: Craig Boerner, (615) 322-4747
craig.boerner@vanderbilt.edu