We’ve all been there. A late night turns to an early morning – little to no sleep in between – with many aspects of our health and wellness taking the hit. Sleep loss can make us eat unhealthy foods, gain weight, impair our mood, memory, decision-making, and worsen our immune system. Lack of sleep increases our risk for cancer, heart disease, stroke, and other serious health problems. Additionally, chronic sleep loss may lead to physical damage to and loss of brain cells which cannot be repaired by “catching up” on sleep later.
We didn’t always understand that lack of sleep could be so dangerous, but Penn was among just a few academic medical centers nationwide that saw the need for sleep research back in the 1970s when the field was still relatively new. Penn started the nation's first multidisciplinary comprehensive sleep center 25 years ago on the belief that sleep research must be a collaborative pursuit with experts from neurology, psychiatry, pulmonary medicine, and other areas.
Today, under the leadership of Allan I. Pack, MD, PhD, chief of Sleep Medicine and director of the Center for Sleep and Respiratory Neurobiology, and David F. Dinges, PhD, chief of the division of Sleep & Chronobiology and director of the Unit of Experimental Psychiatry, Penn researchers are unraveling new insights into sleep disorders and our understanding of the vital role of sleep in overall health.
Earlier this month in Denver at SLEEP 2016, the 30th annual meeting of the Associated Professional Sleep Societies LLC, Penn researchers presented preliminary data on insomnia, sleep apnea, and our understanding of the role of sleep in overall health.
Richard Schwab, MD, co-medical director of the Penn Sleep Center, and colleagues presented on post-FDA approval clinical use of hypoglossal nerve stimulation. The device was approved in April 2014 for patients with moderate to severe sleep apnea who are unable to tolerate a continuous positive airway pressure (CPAP) mask.
In the Penn trial, total apnea-hypopnea index (AHI) – which measures severity of sleep apnea by counting the number of pauses in breathing during sleep – for all patients significantly decreased an average of 35 events per hour after the device was planted, which corresponds to an average reduction of 84 percent. Additionally, the lowest oxygen level measured in the blood during the night significantly increased by 11 percent, from 79 percent to 90 percent.
Namni Goel, PhD, a research associate professor of psychology in Psychiatry in the division of Sleep and Chronobiology, and colleagues presented findings that suggest the amino acid acetylcarnitine – which is sometimes used as a dietary supplement for mental disorders and other conditions -- may help predict an individual’s neurobehavioral performance during chronic sleep restriction.
In other news from the meeting, there was further evidence that those who are having trouble sleeping may be better off just getting out of bed. Michael Perlis, PhD, an associate professor in Psychiatry and director of the Penn Behavioral Sleep Medicine Program, presented preliminary findings that suggest that what may prevent 70 to 80 percent of individuals with new onset insomnia (acute insomnia) from developing chronic insomnia is a natural tendency to self-restrict time in bed.
Electing to stay awake (rather than staying in bed trying to sleep) is not only a productive strategy for an individual with acute insomnia, but is also one that is formally deployed as part of cognitive behavioral therapy for chronic insomnia.
Last month, the American College of Physicians recommended Cognitive Behavioral Therapy (CBT) as the initial, first-line treatment for chronic insomnia, based on data showing the therapy can improve symptoms without the side effects associated with sleep drugs.
“Those with insomnia typically extend their sleep opportunity,” Perlis said, in a WebMD article. "They go to bed early, get out of bed late, and they nap. While this seems a reasonable thing to do, and may well be in the short-term, the problem in the longer-term is it creates a mismatch between the individual’s current sleep ability and their current sleep opportunity; this fuels insomnia."
Andrea M. Spaeth, PhD, a postdoctoral fellow, presented findings that an individual’s body composition and caloric intake can influence time spent in specific sleep stages.
The study was the latest in a series of achievements in the body of knowledge in this area from the same research team. For example, a 2013 study from the Penn team found that those with late bedtimes and chronic sleep restriction may be more susceptible to weight gain due to the increased consumption of calories during late-night hours, and a 2015 study presented at last year’s SLEEP meeting from the group found that eating less late at night may help curb the concentration and alertness deficits that accompany sleep deprivation.
These findings from SLEEP 2016 join additional ongoing sleep studies, many of which span multiple specialties across the Perelman School of Medicine. These relationships continue to yield new insights into growing areas of research including the role of sleep loss and progression of neurodegenerative brain diseases, how several sleep disorders can be a risk factor for types of cancer, and the relationship between sleep and metabolism.