Case Study—Hypnic Headache Syndrome
By Lawrence Newman, MD, Director, Headache Institute, Roosevelt Hospital Center, New York, NY, and Associate Clinical Professor of Neurology, Albert Einstein College of Medicine, Bronx, New York
Mary is a 68-year-old woman who developed headaches approximately five years ago. These headaches involve her entire head, are throbbing and fairly severe. Each headache lasts one to two hours and then spontaneously resolves even without treatment. The headaches are not associated with any other symptoms.
Mary has seen many doctors over the years for these headaches, and has had numerous neurological examinations, blood tests and three MRIs of her brain. Everything has always been normal. She is desperate to “get to the bottom” of these headaches because, curiously, they only strike her at night, always between 1 and 3 A.M. She hasn’t had a good night’s sleep in five years.
In general, headaches beginning for the first time after the age of 50 are a cause for concern. In an older person, new-onset headaches may be the result of a serious disorder such as a brain tumor, stroke, or inflammation of the arteries of the head (a condition called giant cell arteritis). They, therefore, require extensive investigation. Luckily for Mary, these tests have been done and no serious cause of the headache was uncovered. Also, the fact that Mary has had a nightly headache for the past five years without any change in the pattern usually suggests a benign cause.
There are a number of primary (benign) headaches that may have their onset during sleep, most notably cluster and migraine headaches, but these headaches usually begin much earlier in life. Only one specific headache disorder is characterized by the features that Mary describes. Hypnic headache syndrome is a rare, sleep-related, primary headache disorder that usually begins after 50 years of age. It was first described in 1988; more than 90 cases have subsequently been reported. The condition is more common in women.
Hypnic headaches occur at a consistent time each night, usually between 1 and 3 A.M., and may, in rare instances, occur during a daytime nap. In fact, because of this unique pattern, this syndrome has been referred to as the “alarm-clock” headache. The headaches begin abruptly, are diffuse and throbbing, and spontaneously resolve in 15 to 180 minutes. The pain in hypnic headache is usually localized in the front of the head but occasionally affects the sides of the head or the entire head. On rare occasions, the headache only affects one side of the head.
The number of headache attacks varies from patient to patient. The majority of patients suffer from four or more attacks per week; more than half have daily attacks. There are usually no other symptoms, although nausea and light and sound sensitivity may be present.
The treatment of this syndrome begins with reassurance as these headaches, although painful and disruptive of sleep, are nonetheless benign. The medication most often recommended to treat the condition is lithium carbonate, but it is often poorly tolerated. (Lithium side effects included thirst, tremor, increased urination, and confusion.) Other agents that have been reported to effectively treat hypnic headache include bedtime doses of caffeine (40-60 mg tablet or as a cup of coffee) and indomethacin.
Although headaches beginning for the first time after age 50 may be attributable to a serious cause, hypnic headache syndrome is actually a benign headache disorder that affects older patients. The disorder is notable for its propensity to strike only while the patient is asleep.