January 08, 2007
Tyler Curtis, a 13-year-old from Columbia, Md., was literally marching himself around the clock-going to bed later and later and waking up later and later, sometimes as late as 4 p.m. the following afternoon.
Ann Halbower reviews data at the Johns Hopkins pediatric sleep clinic.
When he was able to crawl out of bed and get himself to school, he'd be half-asleep in class. Needless to say, his grades-and self-esteem-suffered. Worse, like many teenage night owls, Curtis couldn't break this exhausting routine. His family physician said his hands were tied; he couldn't prescribe sleep medicine to a child.
"I was pretty much on my own," says Laura Curtis, Tyler's mom.
Facing a state investigation following complaints from Tyler's school about his truancy, and exhausted from trying to manage Tyler's sleeplessness, Laura searched for a pediatric sleep specialist. She found one in pediatric pulmonologist Ann Halbower at the Johns Hopkins Pediatric Sleep Center It turns out that his sleep problem wasn't so rare after all.
"He's sleeping, but not at the right time," says Halbower. "It's one of the more common things I see in teenagers."
Central to Tyler's problem, called delayed sleep phase syndrome, or DSPS, are circadian rhythms, the body's internal clock that tells us when we need sleep. In most people this timer works like clockwork, triggering the release of the sleep hormone melatonin when darkness sets in, then turning it off and arousing the body when morning light seeps through the bedroom shades. But for DSPS victims, this circadian clock runs wild, oblivious to light and darkness, day and night. As hard as patients try, they can't reset this clock.
"If you ask a patient like this to go to bed early, he'll stare at the ceiling in frustration," Halbower says. "When I tell them this is not their fault, they cry because somebody finally recognizes they can't control their sleep."
Halbower treats the disorder much the way she treats jet lag. First, she had Tyler fill out a sleep log over the course of a month. Then, using that data, she applied a combination of melatonin and light therapy to progressively pull Tyler's sleep schedule back. A small dose of melatonin prompted sleepiness, and exposure to "blue-wavelength" light 15 minutes prior to the desired wake-up time aroused the body. Also, Tyler was asked to sit by the light box for another 30 minutes before getting ready for school. Halbower explains that after the light hits the retina, it travels down a nerve bundle to the brain, where it literally resets the sleep phase.
"For patients like Tyler, who have a very low or altered melatonin secretion, you collect information that tells you at what point in his circadian rhythm light will have a major impact on improving his sleep," Halbower says. "In Tyler's case, it's just before his spontaneous wake-up time."
The therapy worked. Today, says his mom, Tyler is able to go to bed earlier, and wake up earlier too-without feeling sleepy.
"He's more alert when he wakes up, and he's in a better mood, too," says Laura. "He's doing much better in school."