Wednesday, June 11, 2008

Day Three of SLEEP 2008 Comes to a Close

The scientific program for the third day of SLEEP 2008 concluded with the final symposia and oral presentations of the day.

Some American Academy of Sleep Medicine
section members are finishing up their section meetings.

The final day of the scientific program on Thursday will consist of symposia and oral presentations lasting from 8 a.m. to 12:15 p.m. The SLEEP 2008 exhibit hall closed this afternoon and will not be open on Thursday.

Insomnia Linked to Increased Risk of High Blood Pressure

“The medical impact of chronic insomnia has been underestimated,” said researcher Alexandros Vgontzas at the conclusion of his oral presentation this afternoon at SLEEP 2008.

In a study (ID# 685) of 1,741 men and women from Central Pennsylvania, Vgontzas and colleagues found that having
insomnia and a short sleep duration of less than or equal to five hours increased the risk of high blood pressure by five times. Having insomnia and sleeping for five to six hours made individuals three times more likely to have high blood pressure. Without a complaint of insomnia, short sleep duration of less than or equal to five hours increased the risk of high blood pressure by only 1.5 times.

Sleep time was recorded during one night in a sleep laboratory. “Insomnia” was defined as a complaint of insomnia for more than or equal to one year.

Vgontzas, of Hershey Medical Center in Hershey, Pa., indicated that these results show that insomnia with a short sleep duration may raise the risk of high blood pressure at a rate that is similar to
obstructive sleep apnea.

The SLEEP 2008 abstract book is available online at

Symposium Examines Causes of Drowsy Driving

A symposium taking place this afternoon at SLEEP 2008 is examining the contributing factors related to drowsy driving. Co-chairs Dr. Naomi Rodgers and Dr. Kenneth Wright Jr., along with a faculty of experts, are presenting the latest information.

According to the
U. S. National Highway Traffic Safety Administration, drowsy driving is a cause of at least 100,000 auto crashes each year. These crashes injure an average of 40,000 people and result in more than 1,550 deaths; the NHTSA suggests that the actual numbers are much higher.

Drowsy-driving crashes tend to occur late at night, are likely to be serious, often involve a single vehicle leaving the roadway, and tend to involve a driver who is alone in the vehicle. In addition to veering off the road, drowsy drivers are likely to wander into another lane or steer into oncoming traffic.

Sleep loss is an obvious factor in drowsy driving. Studies show that sleep deprivation impairs drivers in a manner that is comparable to alcohol, causing lapses in attention and slowing critical reaction times.

Other factors such as late or irregular
work shifts, poor sleep habits and untreated sleep disorders such as obstructive sleep apnea and narcolepsy can combine to make anyone vulnerable to drowsy driving. Young men in their teens and 20s are more likely to be involved in a drowsy-driving crash.

According to the American Academy of Sleep Medicine, tips to avoid drowsy driving include getting a full night of sleep before a long drive and pulling off the road to take a nap if you begin to feel sleepy.

Lecturer Discusses Restless Legs Syndrome

This afternoon at SLEEP 2008, invited lecturer Dr. Christopher Earley is giving a presentation entitled, “Restless Legs Syndrome: From the Bed to the Bench and Back Again.” Earley will review the current understanding of RLS and discuss areas of potential for future research.

Earley is associate professor of neurology and associate director of the
Sleep Disorders Center at Johns Hopkins School of Medicine. For more than 15 years his research has focused on RLS.

In 2007
new studies added to the research that is cracking the complex genetic code behind RLS. According to the American Academy of Sleep Medicine, iron, dopamine and genetics appear to be the primary factors in the development of RLS.

RLS involves a strong, almost irresistible urge to move the legs that worsens at night and disturbs your ability to fall asleep or remain asleep. It occurs more often in women than in men.

Snack Attack: Short Sleep Promotes an Increase in Snacking

A study (ID# 0355) being presented as a poster presentation this afternoon at SLEEP 2008 shows that people who restrict their sleep are likely to increase the amount of snacks they eat. The authors conclude that this behavior may contribute to the increased risk of weight gain and obesity associated with short sleep hours.

The study involved 11 healthy volunteers with an average age of 39 years. Caloric intake was monitored for 14 days when sleep was restricted to 5.5 hours in bed each night, and for 14 days of 8.5 hours in bed each night.

Results show that meal intake remained similar in the two conditions, but subjects consumed more energy from snacks during the period of sleep restriction. The carbohydrate content of snacks also increased during restricted sleep.

Energy expenditure was comparable during the two sleep conditions, as were the levels of leptin and ghrelin, two hormones involved in appetite regulation.

According to the
American Academy of Sleep Medicine, most adults need about seven to eight hours of sleep each night.

The SLEEP 2008 abstract book is available online at

Internet, Aerobic Exercise May Help People with Insomnia

Two studies being presented as poster presentations this morning at SLEEP 2008 offer hope to those who suffer from insomnia.

A study (ID# 0716) of 44 participants shows that a self-help program delivered via the Internet can significantly improve insomnia in adults. Individuals in the study group had an average age of 45 years, and 77 percent were women.

Participants reported having an average of five nights per week of sleep difficulties for about 10 years. The study involved a six-week, structured, interactive, self-guided, and tailored intervention that took traditional face-to-face
cognitive behavioral therapy and transformed it for delivery via the Internet.

Results show that sleep improved significantly over the six-week period. Sleep efficiency (i.e., the percentage of time in bed spent sleeping) improved from 66 percent to 88 percent. The average nightly total sleep time of the participants increased by 80 minutes.

Another study (ID# 0737) of 36 adults with chronic primary insomnia suggests that moderate aerobic exercise can help people with insomnia get some sleep.

The study involved 28 women and 8 men with an average age of 44 years. Results show that a 50-minute session of moderate aerobic exercise on a treadmill improved numerous measures of sleep quality. It decreased sleep onset latency (i.e., the amount of time it takes to fall asleep) by 54 percent and decreased wake time in bed by 36 percent after the exercise session.

The session of moderate aerobic exercise, which began at 6 p.m., also increased total sleep time by 21 percent and increased sleep efficiency by 18 percent.

Similar results were not achieved with either heavy aerobic exercise or moderate strength exercise. Heavy aerobic exercise involved three periods of 10 minutes of exercise on a treadmill alternating with 10 minutes of rest. Strength exercise lasted about 50 minutes and involved: shoulder press, chest press, vertical traction, leg press, leg curl, leg extension, abdominal crunch and lower back.

The SLEEP 2008 abstract book is available online at

Children Who Snore Have Higher Heart Rates

A study (ID# 0253) being presented as a poster presentation this morning at SLEEP 2008 shows that snoring has a significant impact on the cardiovascular functioning of children during sleep.

The study involved 40 children with an average age of 8 years. Children with severe
obstructive sleep apnea (OSA) had the highest average heart rate of 92 beats per minute (bpm). Children with primary snoring had an average heart rate of 82 bpm, which was higher than children with moderate OSA (76 bpm) and children with mild OSA (74 bpm). The heart rate of matched controls was 71 bpm.

The abstract authors conclude that these results challenge the notion that snoring is harmless.

According to the
American Academy of Sleep Medicine, the incidence of snoring in children is reported to be 10 percent to 12 percent.

The SLEEP 2008 abstract book is available online at

Is Sleep the Secret to Successful Aging for Women?

A study (ID# 0305) being presented as a poster presentation this morning at SLEEP 2008 reinforces the importance of normal sleep for the healthy aging of women.

The study involved 2,226 women who were 60 years of age or older. Nearly 21 percent of the women were determined to be “successful agers.” Measures of successful aging included independent living, active engagement with life, life satisfaction and well-being, freedom from disability and the absence of physical disease.

Women who reported less sleep disturbance on an
insomnia rating scale were more likely to be successful agers. Successful aging was best predicted by less daytime napping and fewer complaints of sleep maintenance insomnia (i.e., when awakenings occur during the night).

An increased severity of sleep disturbance predicted lower self-ratings of “successful aging” and a greater difference between perceived and actual age.

According to the
American Academy of Sleep Medicine, women tend to describe sleep problems using different terms than men. Women may be less likely to say that they feel sleepy during the day. Instead women often describe feeling tired, unrested or fatigued. They also may report an overall lack of energy or vitality.

The SLEEP 2008 abstract book is available online at

Workshop Looks Back at Historic 2007 Certification Exam

A workshop taking place this morning at SLEEP 2008 is taking a look back at the historic certification examination in sleep medicine that was administered by member boards of the American Board of Medical Specialties in November 2007.

Although certification for
sleep specialists has been available for more than 25 years, this was the first time that the exam was administered under the umbrella of the ABMS. The exam was offered by the American Board of Internal Medicine, the American Board of Psychiatry and Neurology, the American Board of Pediatrics, the American Board of Family Medicine and the American Board of Otolaryngology. The exam will continue to be offered every two years.

The workshop chair is
Dr. Stuart Quan, who will review both the development of the exam content and the results from the 2007 exam.

American Academy of Sleep Medicine administered a certification examination in sleep medicine from 1978 to 1990, giving specialists in sleep medicine an opportunity to prove their expertise in the diagnosis and treatment of patients with sleep disorders.

The AASM then voted to create the independent American Board of Sleep Medicine, and the ABSM assumed responsibility for the exam from 1991 to 2006.

Child Sleep Patterns around the World

A study (ID# 0185) being presented as an oral presentation this morning at SLEEP 2008 compares the sleep patterns of young children from 12 different countries. Results are based on questionnaires completed by the parents of 21,273 infants and toddlers from zero to 36 months of age.

The study indicates that young children in predominately Caucasian countries have earlier bedtimes and obtain more overall sleep than young children in predominately Asian countries. No differences were found in night wakings or napping behaviors.

Children in New Zealand went to bed the earliest with an average bedtime of 7:16 p.m. Children in Hong Kong went to bed the latest with an average bedtime of 10:10 p.m. U.S. children had an average bedtime of 8:52 p.m.

Japanese children had the lowest total sleep time (i.e., nightly sleep plus daytime naps) of 11.6 hours of sleep per day. Children in New Zealand had the highest total sleep time of 13.3 hours of sleep. U.S. children averaged 12.9 hours of total sleep time per day.

Seventy-six percent of Chinese parents perceived that their child has a small or severe sleep problem. Only 11 percent of parents in Taiwan responded similarly.

According to the
American Academy of Sleep Medicine, newborns up to three months of age need about 16 to 20 hours of total sleep time per day, while infants between three and 12 months old need 14 to 15 hours of total sleep time. Toddlers between the ages of one and four years need about 12 to 14 hours of total sleep time.

The SLEEP 2008 abstract book is available online at