Abstract & Commentary
Synopsis: Although long thought to be indicative of sleep disorders, morning headache has many diverse risk factors. It is a common disorder.
Source: Ohayon MM. Arch Intern Med. 2004;164:97-102.
Sleep and headache have a long and complex relationship.1 Morning (or awakening) headache has been linked to sleep disorders,2 especially obstructive sleep apnea syndrome, but this association is controversial.3 Other associations include bruxism, periodic limb disorders, hypertension, and living with heavy snorers. Ohayon set out to determine the prevalence of morning headache in the general population and to look for correlates among 5 categories of factors (sociodemographic determinants, use of psychoactive substances, organic diseases, sleep disorders, and mental disorders).
Using a sophisticated, computerized telephone script, this study contacted 18,980 people, 15 years or older, living in the United Kingdom, Germany, Italy, Portugal, and Spain between 1994 and 1999. Women comprised 51.3% of the population. People were excluded who could not speak the national language, had a hearing or speech impairment, or had an illness that precluded an interview. There was no attempt to classify the morning headaches into migraine, tension, cluster, or cervicogenic.
Of these participants, 1442 (7.6%) had morning headaches, and 1.3% reported daily morning headaches. On multivariate analysis the following variables were statistically significant: age younger than 25 years or between 45 and 54, female gender, unemployed or homemaker, musculoskeletal disease, hypertension, heavy alcohol consumption (6 drinks/d), use of anxiolytic medication, nightmares of any frequency, insomnia, circadian rhythm disorder, sleep-related breathing disorder, dysomnia NOS (which includes restless leg syndrome and periodic limb movement disorder), loud snoring, anxiety, major depressive disorder with or without anxiety, and stress. Coffee or tobacco consumption, use of antidepressant or hypnotic medication, heart disease, upper airway disease, and other nonpainful diseases were not significant. When the analysis was limited to individuals with daily morning headaches, only hypertension, musculoskeletal disease, heavy alcohol consumption, use of anxiolytics, nightmares = 1 night/week, insomnia, circadian rhythm disorder, sleep-related breathing disorder, dysomnia NOS, and major depressive disorder with or without anxiety remained significant. Individuals with morning headache were more apt to report feeling anxious depressed, inefficient, irritable, fatigued, and overly sensitive to light, touch, and sound during the daytime.
Comment by Allan J. Wilke, MD
A prevalence of 7.6% works out to 1 in 13 people, making morning headache very common. As this study demonstrates, it is not limited to sleep disorders. It is tempting to try to find a "final common pathway" that links these risk factors. For instance, hypoxia could reasonably account for headaches. Obstructive sleep apnea and use of alcohol and psychoactive drugs (through their depressant effects on the respiratory system) could cause hypoxia. However, nighttime duration of hypoxia has not been shown to be associated with morning headache.4 Anything that might disturb sleep (pain from a musculoskeletal disorder, insomnia, nightmares, dysomnia, etc) could cause headaches secondary to sleep deprivation.5,6 Other studies have confirmed the association between mood disorders and morning headaches,7 but not all patients with morning headache have a mood disorder. This study did not ask whether the subject was sleeping with someone who was a loud snorer, although you may surmise this based on the increased numbers of females and homemakers with morning headache. A previous study demonstrated disturbed sleep, morning headache, and daytime sleepiness among women living with a snoring spouse.8 This phenomenon was discussed in Internal Medicine Alert earlier this year.9 There does not appear to be a unifying theme; it is likely that morning headache is a multifactorial syndrome.
Dr. Wilke, Assistant Professor of Family Medicine, Medical College of Ohio, Toledo, OH, is Associate Editor of Internal Medicine Alert.
1. Dodick DW, et al. Headache. 2003;43:282-292.
2. Jennum P, Jensen R. Sleep Med Rev. 2002;6:471-479.
3. Jensen R, et al. Acta Neurol Scand. 2004;109:180-184.
4. Greenough GP, et al. Sleep Med. 2002;3:361-364.
5. Blau JN. Cephalalgia. 1990;10:157-160.
6. Spierings EL, et al. Headache. 2001;41:554-558.
7. Neau JP, et al. Cephalalgia. 2002;22:333-339.
8. Ulfberg J, et al. Health Care Women Int. 2000;21:81-90.
9. Phillips BA. Internal Medicine Alert. 2004;26:10-11.