May 8, 2000 -- Nearly 30 years have passed since Anna Wirz-Justice, MD,
first prescribed a night without sleep for a severely depressed 80-year-old
woman. "She used to just sit around all day, feeling suicidal," says
the Swiss neurobiologist. "She hardly spoke or moved.''
Serotonin acts as a neurotransmitter, a type of chemical that helps relay signals from one area of the brain to another. Although serotonin is manufactured in the brain, where it performs its primary functions, some 90% of our serotonin supply is found in the digestive tract and in blood platelets.
By the next morning, the elderly woman "was talking and moving around as
if she were actually another person," Wirz-Justice says. "She told me
that at about two or three in the morning, she felt like a black cloud had been
lifted from her shoulders."
Was Wirz-Justice on to something? She and other researchers thought so -- at
first. There is no denying that sleep deprivation temporarily eases depression.
Up to 60% of depressed people will show a 30% improvement after just one night
awake, according to a review article published in the January 1990 issue of the
American Journal of Psychiatry. People who feel the most depressed in
the morning and improve later in the day seem to benefit the most from a night
But there was a problem: Patients tended to relapse into depression as soon
as they did get a good night's sleep. Moreover, habitual sleep deprivation may
be linked to long-term health problems such as high blood pressure and
diabetes. The challenge then became to find a way of relieving depression by
tinkering with sleep-wake cycles.
Tapping the Power of Hormones
Today, researchers are experimenting with ways to make use of the body's
biological clock -- its circadian, or 24-hour, rhythms -- without asking
patients to abandon rest altogether. The solution may lie in timing sleep to
benefit from certain hormones that ebb and flow throughout the day.
For instance, thyroid stimulating hormone (TSH) helps control our metabolism
and, indirectly, our levels of energy. An estimated 25% to 35% of depressed
patients have low TSH levels. In recent years, researchers at the National
Institute of Mental Health have found that sleep inhibits the release of TSH,
while staying awake through the night and the early morning hours boosts
Some researchers are trying to manipulate the body's hormonal tides by
having patients stay awake through the early morning hours for about a week.
Doctors at the University Hospital of Freiburg in Germany tried this experiment
on a group of depressed patients who felt better after one night without sleep:
They told the patients to go to sleep at 5 p.m. that evening and rest until
midnight the next night -- a total of 31 hours. Then the patients gradually
eased back to a normal sleep cycle over the course of the week. One night they
slept from 6 p.m. until 2 a.m., the following night from 7 p.m. until 3 a.m.,
until finally they returned to an 11 p.m. to 6 a.m. sleep cycle. Remarkably,
the majority -- 75% -- didn't relapse into depression, according to results
published last fall in the European Archives of Psychiatry and Clinical