Poor sleep may increase women's vulnerability to mood disorders, according
to speakers at a recent two-day workshop on women and sleep held in
Washington, D.C.
Women of all ages are more apt than men to report trouble falling asleep,
staying asleep, and waking too early or unrefreshed. Women are 1.4 times more
likely to develop insomnia than men, according to a meta-analysis of 29
studies involving nearly 1.3 million adults published in Sleep in
January 2006, said Christopher Drake, Ph.D., an assistant professor of
psychiatry and behavioral neurosciences at Wayne State University School of
Medicine. The gender differences in insomnia emerge at puberty and increase
with age.
A primary symptom of depression, insomnia also may be an independent
comorbid condition, said Drake, one of two dozen speakers at the workshop,
which was co-sponsored by the National Sleep Foundation and the Atlanta School
of Sleep Medicine. Specific treatment of insomnia may, however, improve sleep
and ease depression, he noted. Sleep disturbance is the single most common
refractory symptom in successfully treated depressed patients, and it
increases the risk of relapse.
Women also have higher rates of chronic pain disorder than men do, a
condition often comorbid with insomnia, Drake said. Behavioral treatment of
pain-related sleep disturbance often benefits sleep and reduces pain.
Sleep laboratory studies reveal gender differences in sleep regulation in
depressed women and men, said Roseanne Armitage, Ph.D., a professor of
psychiatry and psychology and director of the Sleep and Chronophysiology
Laboratory in the University of Michigan's Depression Center.
In depressed women, a small sleep challenge—delaying the onset of
sleep by three hours—evokes an increase in slow-wave restorative sleep
activity equivalent to that seen with total sleep deprivation in healthy
women. It takes total sleep deprivation to evoke a response in depressed
men.
Since the same brain mechanisms involved in sleep regulation are involved
in mood regulation, Armitage said, this finding meshes with the phenomenology
of depression. Depressed women tend to have more changeable or fluctuating
mood, whereas depressed men tend to have flat, depressed mood.
Armitage's review of gender- and age-related sleep abnormalities in
depression was published in the February Acta Psychiatrica
Scandinavia.
Insomnia, depression, fatigue, and hypothyroidism are common but
underrecognized presenting symptoms in women with obstructive sleep apnea
(OSA), said Nancy Collop, M.D., an associate professor of medicine at the
Johns Hopkins University School of Medicine and president of the American
Board of Sleep Medicine. People with OSA may stop breathing dozens, even
hundreds of times a night.
OSA historically has been viewed as a male disease, Collop said. The
typical male patient snores loudly, is obese, and complains of daytime
sleepiness. Failure to appreciate gender differences in OSA symptoms may
prompt misdiagnoses of women and delay their referral to sleep specialists,
she maintained. OSA, a risk factor for heart attacks and strokes, affects an
estimated 4 percent of middle-aged men and 2 percent of middle-aged women.
Depression and anxiety are common complaints in people with restless legs
syndrome (RLS), a disorder that affects women roughly twice as often as it
affects men, said Barbara Phillips, M.D., a professor of medicine at the
University of Kentucky's Chandler Medical Center and chair of the National
Sleep Foundation's board. RLS often emerges during pregnancy and usually
resolves promptly following delivery. It may reappear in subsequent
pregnancies or later in life.
Symptoms of RLS worsen with inactivity and show a circadian pattern,
peaking at night and disrupting sleep. RLS patients often report a diminished
quality of life.
Selective serotonin reuptake inhibitors (SSRIs) used to treat depression
may exacerbate RLS, Phillips cautioned. Older antihistamines in some
over-the-counter sleep aids and antiemetic drugs also may have this
effect.
About 85 percent of people with RLS experience periodic leg movements of
sleep (PLMS), a disorder involving frequent repetitive leg jerks that cause
transient partial arousals. While sleepers with PLMS often focus on their
daytime fatigue, bed partners alert them to their nighttime behavior. Some
antidepressants induce or worsen PLMS, too, Phillips said. Small studies
suggest that bupropion may be less likely than SSRIs to worsen RLS and
PLMS.
Dopamine agonists are first-line treatments for RLS. They are so effective
in relieving RLS symptoms, she said, that lack of response to therapeutic
doses should prompt reassessment of the diagnosis.
"Because sleep disturbance often is a marker of mood disturbance, and
because both mood disturbances and the medications used to treat them may
disrupt sleep," said Phillips. "asking about sleep is an important
part of ongoing psychiatric care."
A conference summary is scheduled to be posted at<www.sleepfoundation.org>.▪