Wednesday, June 10, 2009

Third Day of SLEEP 2009 Wrapping Up

The final discussion group, symposia and oral presentations for the third day of SLEEP 2009 are underway and will conclude at 4:45 p.m. Pacific Time.

The final day of the scientific program will begin
Thursday at 8 a.m. Pacific Time with three symposia and more oral presentations. SLEEP 2009 will conclude at 12:15 p.m. tomorrow.

The Neurobiology of Narcolepsy

Dr. Thomas Scammell, associate professor of neurology at Harvard Medical School, is presenting an invited lecture this afternoon from 1:30 p.m. to 2:30 p.m. Pacific Time on the subject of the “Neurobiology of Narcolepsy.”

Scammel is studying mice to gain a detailed understanding of the neurobiology of orexin, hoping that this will contribute to the development of effective therapies for patients with
narcolepsy and enhance the understanding of sleep.

In April his study, “Feeding-elicited cataplexy in orexin knockout mice” was published online ahead of print in the journal Neuroscience. In the Jan. 1 issue of the journal SLEEP Scammel published, “A consensus definition of cataplexy in mouse models of narcolepsy.”

In May the Sleep Education Blog reported on an important new genetic study, which suggests that narcolepsy is an autoimmune disorder. Read the
full report.

REM Sleep Affects Emotions & Mood

Two studies being presented today shed light on the importance of rapid eye movement (REM) sleep.

A study (#1284) being presented as a poster until 12:15 p.m. Pacific Time reports that in both men and women, REM appears to modulate negative affect; in females, REM also may modulate negative autobiographical memories. According to the study’s author, the results suggest that severe depression in women may be associated with an excess of REM sleep.

Another study (#0379) that will be presented this afternoon as an oral presentation suggests that REM sleep may enhance the brain’s empathetic capacity toward positive emotions. Results show that participants who did not take an afternoon nap displayed an amplified reaction to expressions representing anger and fear when tested on a face-rating task at 5 p.m. In contrast, participants who had an afternoon nap opportunity lasting 60 to 90 minutes displayed an increased receptiveness to happy facial expressions following sleep; however, this beneficial effect was found only in participants who achieved REM sleep during the nap.

The
American Academy of Sleep Medicine reports that sleep involves multiple stages that make up a sleep cycle. Each complete cycle lasts about 90 to 110 minutes; most adults will go through four to six cycles in a full night of sleep. REM sleep tends to be the final stage of the sleep cycle in normal adult sleep. Most dreams occur during this sleep stage. Find more about the stages of sleep on SleepEducation.com.

You can
download the SLEEP 2009 abstract supplement as an 11 MB file in PDF format.

Sleepless and Stressed

A study (#1268) being presented this morning as a poster reports that there is a bidirectional relationship between stress and poor sleep.

Results show that higher habitual stress is associated with reported shorter sleep duration, poorer sleep quality, and daytime functioning impairments. Conversely, daytime functioning impairments and shorter sleep duration demonstrated a predictive relationship with habitual stress complaints.

In February the Sleep Education Blog
reported that stress related to the struggling economy can have a negative impact on sleep. On SleepEducation.com the American Academy of Sleep Medicine describes how job stress can affect sleep.

You can
download the SLEEP 2009 abstract supplement as an 11 MB file in PDF format.

Sleep & Women: Rheumatoid Arthritis

A study (#1007) that will be presented later this morning as a poster indicates that women with rheumatoid arthritis report poor sleep quality.

The study involved 133 women with RA; their average age was 56 years and they had RA for an average of almost 15 years.

Results show that 71 percent of the women had poor self-reported sleep quality. Pain, depression and poor adherence to RA medications also contributed to impaired sleep.

The American Academy of Sleep Medicine reports that many medical and neurological disorders may give rise to chronic insomnia. Disorders that cause pain, breathing problems, limited mobility, and central nervous system (CNS) symptoms are the major ailments that cause difficulty initiating and maintaining sleep. Find more about
insomnia due to medical condition on SleepEducation.com.

You can
download the SLEEP 2009 abstract supplement as an 11 MB file in PDF format.

Complementary and Alternative Medicine for Sleep

“The Use of Complementary and Alternative Medicine for Sleep” is a symposium that is taking place until 10 a.m. Pacific Time. One topic being discussed is the use of meditation and yoga for the treatment of insomnia.

A small pilot study (#0874) presented yesterday reported that Kriya Yoga – a type of meditation that combines different yoga techniques – may be an effective behavioral treatment for chronic primary insomnia.

Another topic being discussed is the efficacy of acupuncture on sleep in depressed pregnant women. In February the Sleep Education Blog reported on a new scientific review of acupuncture use for insomnia. The authors conclude that acupuncture has potential as an insomnia treatment, but there is only limited evidence to support its use. Read the
full report.

In 2006 the
National Center for Complementary and Alternative Medicine (NCCAM), part of the National Institutes of Health, reported that more than 1.6 million American adults use some form of CAM to treat insomnia or trouble sleeping.

A
2007 study of CAM use published in the journal SLEEP reported that large segments of the U.S. population use valerian or melatonin for insomnia, and usage typically falls outside the purview of the health-care system.

Using Melatonin to Treat Circadian Rhythm Sleep Disorders

A symposium taking place until 10 a.m. Pacific Time is addressing the clinical use of melatonin. “Melatonin Treatment of Sleep and Circadian Disorders” is focusing on the two therapeutic effects identified for melatonin: using low-dose melatonin for circadian phase shifting, and using high-dose melatonin for acute sleep promotion.

“Practice parameters for the clinical evaluation and treatment of circadian rhythm sleep disorders,” published by the
American Academy of Sleep Medicine in a 2007 issue of the journal SLEEP, includes recommendations for using melatonin to treat circadian rhythm sleep disorders such as shift work and jet lag. View the practice parameters online.

Sleep & Motherhood

Two studies that will be presented later this morning as posters examine issues related to sleep and motherhood.

One study (#0143) reports that although postpartum mothers’ sleep is disturbed and leads to significant daytime consequences, the timing of their nocturnal sleep may be preserved. Results show that the actual bedtimes and wake times of first-time mothers of newborns were positively correlated with their preferred times. Mothers with both a newborn and other children also tended to fall asleep at their preferred time, but they woke up earlier than their preferred time.

Another study (#0243) suggests that parental presence at bedtime appears to be the factor that impacts sleep more than literal co-sleeping. The study involved parents of 29,287 infants and toddlers from 17 countries. Results show that in predominately Caucasian countries, bed sharing was reported by 11.8 percent of parents and room sharing by 22 percent; in predominately Asian countries these figures were 64.7 percent and 86.5 percent. In predominately Caucasian countries, children who slept in a separate room obtained more sleep, woke less at night, had less difficulty at bedtime, fell asleep faster, and were perceived as having fewer sleep problems; only 40.9 percent of their parents were present with them at bedtime.

Last year at SLEEP 2008 the same research team
reported that young children in predominately Caucasian countries have earlier bedtimes and obtain more overall sleep than young children in predominately Asian countries. U.S. children had an average bedtime of 8:52 p.m. and averaged 12.9 hours of total sleep time per day.

You can
download the SLEEP 2009 abstract supplement as an 11 MB file in PDF format.

Caffeine Prevents Risk Taking After 75 Hours of Sleep Deprivation

A study (#0473) that will be presented later this morning as a poster reports that caffeine use prevents increased risk taking after 75 hours of total sleep deprivation.

The study at the
Walter Reed Army Institute of Research involved 25 healthy adults between 20 and 35 years of age who were deprived of sleep for three nights. Twelve participants received 200 mg caffeine gum bi-hourly from 1 a.m. to 7 a.m. each morning (for a total of 800 mg per morning); 13 participants received identical placebo gum.

A behavioral task of risky behavior was administered after 51 hours of wakefulness and again after 75 hours of sleep deprivation. Results show that risk taking was unaffected in the placebo group after 51 hours, but increased significantly by 75 hours.


The caffeine group remained unchanged at both time points and was significantly less risky than the placebo group at 75 hours. The study suggests that extreme sleep deprivation may cause individuals to reach a “breaking point” at which they are less likely to inhibit risky behavior.

You can download the SLEEP 2009 abstract supplement as an 11 MB file in PDF format.

Sleep & Growing Older

Three studies that will be presented later this morning as posters shed light on issues related to sleep in older adults.

A study (#0363) involving Sleep Heart Health Study participants used direct measures of sleep fragmentation to show that increases in specific sleep stage transitions during the night are associated with higher mortality risk. This association was found in middle-aged and older adults who had more objectively measured wake to non-rapid eye movement (NREM) sleep transitions per hour of sleep, and in participants who had more NREM to wake transitions. Over the average follow-up period of eight years, 854 of the 5,614 participants died (15.2 percent).

A study (#0373) involving a national sample of older Americans shows that more than 55 percent reported sleeping for an average of seven hours or less per night during the past month. But only 18 percent reported that they “often” or “almost always” feel “unrested during the day.” The average age of the 1,570 participants was 71.9 years.

Another study (#0420) reports that older adults (between 59 and 82 years of age) showed more resiliency to total sleep deprivation than younger adults (between 19 and 38 years of age) on a range of measures of cognitive performance. Participants completed three cognitive tasks before and after sleep deprivation lasting 12 hours and 36 hours. For all three tasks, young adults significantly declined during total sleep deprivation while older adults did not change significantly.

You can
download the SLEEP 2009 abstract supplement as an 11 MB file in PDF format.

Sleep Promotes Academic Success

A study (# 0312) that will be presented later this morning as a poster found that reports of better sleep across both the weekdays and the weekend appear to be positively associated with educational success.

The study involved 56 students between 14 and 18 years of age. Each of them had complaints of daytime sleepiness and/or insufficient sleep at night.

Although higher sleep quality and sleep efficiency tended to be related to higher overall grades, specific subjects were related to different sleep measures. Higher math scores were related to fewer awakenings, less time in bed, higher sleep efficiency and better sleep quality. Higher English scores were associated with fewer awakenings during the night, and both English and history scores were associated with less difficulty awakening in the morning.

Another study (#0161) presented yesterday reported that being a “night owl” or “evening type” is associated with lower academic performance in college and a decline in academic performance from high school to college.

You can download the SLEEP 2009 abstract supplement as an 11 MB file in PDF format.

It’s Complicated: Sleep, Marriage & Relationships

Three studies that will be presented later this morning as posters examine the association between sleep and a couple’s relationship.

One study (#1248) reports that being stably married or gaining a partner is associated with better subjective sleep quality and objective sleep efficiency than being unmarried or losing a partner. The study’s lead author presented similar findings last year at SLEEP 2008, reporting that marital happiness may lower the risk of sleep problems in Caucasian women, while marital strife may heighten the risk. Read a press release about last year’s study. Earlier in 2009 in the journal Behavioral Sleep Medicine, the same team published their finding that happily married women reported fewer sleep disturbances, with the association evident among Caucasian women and to a lesser extent among African-American women.

Another study (#1295) involving 159,856 participants found that sleep disturbance is associated with being unmarried. The rates of self-reported sleep disturbance classified by marital status were 16.3 percent for married, 21.2 percent for divorced, 21.3 percent for never married, 22.8 percent for unmarried couple, 25.4 percent for widowed and 30.7 percent for separated. “Sleep disturbance” was defined as seven or more days of having trouble falling asleep, staying asleep or sleeping too much over the last two weeks. Less education, lower income and being unemployed also were associated with sleep disturbance.

A third study (#1285) reports that bidirectional associations appear to exist between sleep quality and interpersonal interactions of co-sleeping couples. Sleep problems at night may have a negative impact on relationship satisfaction the following day, while daytime interactions may influence the quality of sleep that night.

You can
download the SLEEP 2009 abstract supplement as an 11 MB file in PDF format.

Day Three of SLEEP 2009 Will Start at 8 a.m. Pacific Time

The third day of the SLEEP 2009 scientific program will begin in about three hours at 8 a.m. Pacific Time.

The day will begin with six more symposia from 8 a.m. to 10 a.m. Research abstracts will be presented as posters from 10:15 a.m. to 12:15 p.m. A variety of other sessions will take place throughout the day until 4:45 p.m.

View today’s
session schedule.