Finds Insomnia May
Affect Immune System
People with chronic sleep deprivation
may be more susceptible to illness than those who regularly get
a good night's sleep, according to researchers in Canada.
Insomnia affects about nine to
12 percent of the population. Those with the condition have trouble
falling asleep or staying asleep throughout the night, or they
wake up early in the morning and can't fall back to sleep. Some
people have a combination of these symptoms.
Recent studies have shown that
insomniacs rate their lives as more stressful than good sleepers
It is also commonly believed that
not getting enough sleep leads to vulnerability to illness, and
an inability to sleep may slow recovery in those who are already
sick. Dr. Josée Savard and colleagues of the Universite Laval
in Quebec set out to investigate if there is truth to this belief.
They studied the immune responses
of 17 people with chronic insomnia and compared them to 19 good
sleepers. All were between the ages of 18 and 45..
Excluded from the study were pregnant
women, anyone with a sleep disorder (such as sleep apnea), psychiatric
disorder or self-reported medical problems, and those who had
recently taken medication that might affect their sleep.
All 36 participants kept sleep
diaries for three weeks. They recorded the times they went to
bed and woke up, as well as how long it took them to fall asleep
and how many times they woke up in the night and for how long.
After two weeks, the participants
were interviewed and had blood drawn to measure the number of
immune cells in their bloodstream.
When Savard and colleagues compared
the blood tests of both groups, they found that the insomniacs
had fewer CD3, CD4, and CD8 cells than the good sleepers. These
cells are involved in the body's natural defense against certain
infections. Other immune cells did not appear to be affected by
The findings are published in the
journal Psychosomatic Medicine.
Chronic insomnia probably increases
susceptibility to illnesses like the common cold, but there is
no evidence to suggest that insomniacs have an increased risk
for more serious diseases, according to Savard.
"Although this data suggests that
insomnia has a deleterious effect on immunity, insomniacs should
not panic about this," Savard told Reuters Health. "Worrying about
the potential consequences on health due to insomnia only makes
the problem worse."
The conclusion from this study
is that chronic insomnia seems to be associated with altered immunity,
according to the researchers. But additional work is needed to
determine if there is an optimal quantity of sleep to maintain
good immune functioning.
Experiencing occasional sleepless
nights does not qualify as insomnia, and Savard said that immune
function probably goes back to normal in these individuals after
getting a good night's sleep.
For chronic insomniacs the researchers
recommend seeking treatment such as cognitive-behavioral therapy.
Savard said the long-term results are better than those achieved
with sleeping pills.
SOURCE: Psychosomatic Medicine
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