Dov Michaeli
First posted 7/10/11 on The Doctor Weighs In
For Laurie
Who among us hasn’t spent at one time or another a sleepless night, tossing and turning, praying for the light of dawn to finally redeem us from our private sleepless hell? Racing thoughts, emotional distress –conspiring to torment us into tired wakefulness –are the demons of the night. Thankfully, for most of us this is a passing experience. We bounce back, have a good night’s sleep, and barely remember that nightmare of sleeplessness. But not all of us. If you suffer from difficulty getting to sleep or staying asleep, or having nonrefreshing sleep for at least 1 month you are an insomniac.
What is insomnia?
There are two types of insomnia. Primary insomnia refers to insomnia that is not caused by any known physical or mental condition. The most common causes of primary insomnia are stress, anxiety, alcohol and coffee. Secondary insomnia results from a medical condition, the most common being depression.
The treatment can be behavioral, such as not having coffee of alcohol at least 2 hours before bedtime, not exercising before going to sleep, going to bed at a fixed time, using the bed only for sleep (and sex, I hasten to add), and not staying in bed if you can’t fall asleep within 30 minutes –get up and do something relaxing, write down what is bothering you so as to “get it out of your system”, and go back to bed when you feel sleepy. When all fails, a benzodiazepine such as valium, dalmane, Restoril or Ambien, or a minor tranquilizer like Xanax can be used.
But anybody who had to resort to drugs will tell you –it’s not a very pleasant option. Cheerful drug ads notwithstanding, you don’t feel cheerful and refreshed in the morning; many feel quite groggy for hours before the drug effects wane.
Chill it –a new treatment?
Out of left field (actually out of SLEEP 2011, the 25th Anniversary Meeting of the Associated Professional Sleep Societies LLC, in Minneapolis) comes this surprising announcement: people with primary insomnia may be able to find relief by wearing a cap that cools the brain during sleep.
Surprising, but not totally unexpected. fMRI studies of healthy individuals as they fell asleep showed a reduction in metabolism in the frontal cortex in those without insomnia, but insomniacs experienced an increasedmetabolism compared with healthy volunteers, both before going to sleep and during non–rapid eye movement (NREM) sleep (the first stage of sleep, preceding REM sleep). Other evidence suggests that people with insomnia have a generally higher metabolism, including faster heartbeats and hyperarousal. Which brings to mind the advice for excessive physical or emotional arousal –take a cold shower. Not to be too clinical about it, it has a sound scientific basis: reducing body temperature slows down body metabolism, including the brain, and allows a cooler head to prevail. More to the point, neurosurgeons have been using cooling (hypothermia) to reduce brain metabolism in stroke, removal of brain tumor, and trauma. When Buffalo Bills tight-end Kevin Everett was paralyzed after making a head-first tackle in a September 2007 game, the treating spinal surgeon quickly lowered his body temperature for hypothermia therapy by infusing cold saline IV during the ambulance ride to the hospital. Although initially Everett was quadriplegic, within a month he was walking with the help of a walker.
Armed with this knowledge, the University of Pittsburgh team designed a cap that could be used to apply cooling to the frontal cortex. Eight patients with primary insomnia wore the cap which delivered either neutral temperature (control) or a mild hypothermic effect for 60 minutes. The treatment was applied before bedtime and during the first cycle of NREM sleep. The researchers analyzed core body temperature and NREM sleep using PET scanning.
Hypothermic treatment led to reduced metabolism in the underlying frontal and cingulate (which lies next to the frontal) cortex. Five of 8 patients experienced reduction in whole brain metabolism with the treatment.
Treatment also led to an accelerated reduction in core body temperature at sleep onset.
All very interesting, but did it help the patients sleep better? The answer is a resound yes: 75% of the patients reported sleep-related improvements, including a decrease in distracting thoughts, improved sleep maintenance, and more refreshing sleep.
Mind you, 75% of 8 patients is 6. Small numbers indeed, but a promising result nonetheless, which should become a basis for larger studies. In the meantime, can you try the cap yourself? It is not available yet, but Dr. Nofziger, the lead author of the study, is commercializing its production.
Sometimes the most brilliant ideas are also astonishingly simple. This is one of them.
Dov Michaeli MD PhD is a basic researcher writing at The Doctor Weighs In.