Whether they end up with a minor whiplash injury or a concussion, people who suffer head injuries don’t usually just get over it. It takes some time. One problem many face is disrupted sleep, with as many as 45% to 60% of people who’ve had head injuries reporting sleep problems that last months, sometimes years. This can lead to lingering problems including cognitive impairment and emotional distress. Typically these sleep complaints are diagnosed as insomnia — but a recent study reveals that sleep problems following head injury may actually represent a circadian rhythm sleep disorder (CRSD). One of the most common is delayed sleep phase syndrome, characterized by an inability to fall asleep and wake up at appropriate times. As a result, people are often drowsy. The difference between insomnia and CRSD is important, since misdiagnosis of CRSD patients as insomniacs might lead to prescription of inappropriate medications.
Liat Ayalon, PhD, a sleep researcher at the University of California, San Diego, was the lead author of the study, which looked at two particular types of CRSD. People with CRSD in the study either had delayed sleep phase syndrome (meaning they fall asleep or wake up more than two hours later than considered normal) or they had irregular sleep-wake patterns in which they may want to go to sleep in the early evening, the wee hours of the morning or even midday.
“A good night’s sleep is essential to the recovery from any kind of trauma,” says Dr. Ayalon. Patients with untreated CRSD frequently experience continued poor quality of life, depression and cognitive impairment, as well as an exacerbation of pain and anxiety, she adds. Drugs aren’t the solution. CRSD responds to a careful protocol of early-morning bright light exposure and timed intake of melatonin.
Dr. Ayalon suggests that anyone who has suffered a mild head injury and now has problems with sleep might want to consult a sleep specialist. You can prepare for that by keeping a sleep log over seven days or so, noting bed and waking times, which will help pin down the diagnosis. And she suggests that a good way to start correcting CRSD at home is by simply getting out into the morning sunlight for a little walk.