An article published in the April, 2003, issue of Neurology1, the journal of the American Academy of Neurology, reports the findings of a study2 that compared the prevalence of snoring in a study group of chronic daily headache (CDH) sufferers with a group of episodic headache sufferers. The findings? Habitual snoring was more common in those with CDH than in those with episodic headache.
Is Chronic Daily Headache?
CDH is typically defined as head pain occurring daily, or nearly daily, at least 15 days a month. Within the classification of CDH, there are subtypes:
- Chronic tension-type headache (CTTH)
- Chronic Migraine (CM)
- Hemicrania continua (HC)
- New daily persistent headache (NDPH)
In the opening of this article, the authors comment,
"Little is known about risk factors for CDH. Case studies of specialty patients and two population studies suggest that headache is associated with sleep disorders in general, including sleep-disordered breathing. Sleep-disordered breathing has also been strongly associated with cluster headache. However, the risk of CDH associated with snoring has not been assessed in a population sample."
Participants in the study were asked how often they snored and their headache features (pulsatility, nausea, etc.) Following the International Headache Society diagnostic criteria, their head pain was classified as migraine, tension type, or unclassified. Variables evaluated that needed to be taken into account during the study included age, gender, marital status, body mass index, alcohol intake, and lifetime history of diagnosed hypertension (factors associated with sleep-disordered breathing), and current depression caffeine intake and use of opioid analgesics (factors related to chronic headache and sleep disturbances). Scher, Lipton, and Stewart wrote,
We were concerned that the validity of self-reported snoring and predictive value for sleep-disordered breathing might vary by demographic factors. As such, separate regression models were also completed by gender, age (<40 years, >40 years), marital status (married, not married), and headache type (migraine, tension type, unclassified)."
Results and Authors' Discussion Points:
- CDH subjects were more likely to be to be habitual (daily) snorers that episodic headache subjects. Those who said they "always snore" comprised 24% of participants with CDH and 14% of those with episodic headache.
- Taking into account the variables listed above did not significantly affect the results.
- It's accepted that headache my cause sleep disorders while the inverse is also true - sleep disorders can cause headache and trigger Migraines.
- Medications with sedating properties that are used to treat pain or depression may aggravate the breathing associated with some sleep disorders.
- Both too little and too much sleep are known Migraine triggers.
- Sleep-disordered breathing, such as that resulting from sleep apnea may result in headache because such breathing can cause hypoxemia, hypercapnia, and changes in the natural sleep patterns.
- Even in people without sleep apnea, habitual snoring has been associated with headache in other studies.
- Disruptions in sleep from repeatedly awakening could be the common mechanism which causes headache resulting from both snoring and sleep apnea.
- Headache has been reduced or eliminated in some patients through correction of obstructive sleep apnea, but it is unknown if eliminating snoring not related to sleep apnea would achieve the same results.
- Future studies need to include more detailed
assessment of sleep and snoring.
A.I. Scher, PhD; R.B. Lipton, MD; and W.F. Stewart, PhD.
"Habitual snoring as a risk factor for chronic daily headache."
2 The study was supported by GlaxoSmithKline, the Migraine Trust and the American Headache Society.
Last updated March 30, 2006.