In these abstracts are two factors which have not been subject to our conversations so far: the impact of anxiety & depression on sleep and the role of body weight (Body Mass) on CH. Keep your eye open.......
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Headache. 2003 Mar;43(3):282-92.
Erratum in:
Headache. 2004 Apr;44(4):384.

Clinical, anatomical, and physiologic relationship between sleep and headache.

Dodick DW, Eross EJ, Parish JM, Silber M.

Department of Neurology, Mayo Clinic, Scottsdale, Ariz. 85259, USA,

The intimate relationship between sleep and headache has been recognized for centuries, yet the relationship remains clinically and nosologically complex. Headaches associated with nocturnal sleep have often been perceived as either the cause or result of disrupted sleep. An understanding of the anatomy and physiology of both conditions allows for a clearer understanding of this complex relationship and a more rational clinical and therapeutic approach. Recent biochemical and functional imaging studies in patients with primary headache disorders has lead to the identification of potential central generators which are also important for the regulation of normal sleep architecture. Medical conditions (e.g. obstructive sleep apnea, depression) that may disrupt sleep and lead to nocturnal or morning headache can often be identified on clinical evaluation or by polysomnography.

In contrast, primary headache disorders which often occur during nocturnal sleep or upon awakening, such as migraine, CLUSTER HEADACHE, chronic paroxysmal hemicrania, and hypnic headache, can readily be diagnosed through clinical evaluation and managed with appropriate medication. These disorders, when not associated with co-morbid mood disorders or medications/analgesics overuse, seldom lead to significant sleep disruption. Identifying and classifying the specific headache disorder in patients with both headache and sleep disturbances can facilitate an appropriate diagnostic evaluation. Patients with poorly defined nocturnal or awakening headaches should undergo polysomnography to exclude a treatable sleep disturbance, especially in the absence of an underlying psychological disorder or analgesic overuse syndrome. In patients with a well defined primary headache disorder, unless there are compelling historical or examination findings suggestive of a primary sleep disturbance, a formal sleep evaluation is seldom necessary.

PMID: 12603650
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Cephalalgia. 2005 Jul;25(7):488-92.

Investigation into sleep disturbance of patients suffering from cluster headache.

Nobre ME, Leal AJ, Filho PM.

Department of Neurology, Universidade Federal Fluminense, Niterói, Brazil. menobre@rjnet.com.br

The new discoveries relating to cluster headache (CH) encouraged the study of the relationship of the hypothalamus to respiratory physiology and its comorbidity with sleep apnoea. The question is whether the apnoeas are more frequent during REM sleep and the desaturations could be involved as triggers of the cluster attacks. Furthermore, could the connection with the hypothalamus, already proved, be responsible for an alteration in the structure of REM sleep and a chemoreceptor dysfunction. We set out to analyse when polysomnography investigation is necessary in patients with CH. We studied 37 patients suffering from episodic CH, 31 (83.8%) men and six (16.2%) women. For the control group, we selected 35 individuals, 31 (88.6%) men and four (11.4%) women.

There was a greater percentage of obstructive sleep apnoea (OSA) in patients with CH (58.3%) compared with the control group (14.3%) and with the general population (2-4%). In cases of pain during sleep, the majority is deflagrated during the REM phase, following a desaturation episode. A stratified analysis of the apnoea/hypnoea index relating to body mass index (BMI) and age showed that patients with CH have 8.4 times more chance of exhibiting OSA than normal individuals (P < 0001). This risk increases to 24.38 in patients with a BMI > 25 kg/m(2) and increases to 13.5 in patients > 40 years old. Surprisingly, the risk decreases sharply in patients with a BMI < 25 kg/m(2) and who are < 40 years old. Due to the fact that polysomnography is a complex, costly and sometimes difficult examination, we suggest, in concordance with the results, that it should be carried out routinely in patients with CH that exhibit a BMI of > 25 kg/m(2) and/or in patients who are > 40 years of age.

Publication Types:
Clinical Trial
Controlled Clinical Trial
PMID: 15955035 [PubMed]
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Headache. 2006 Oct;46(9):1344-63.
Headache and sleep disorders: review and clinical implications for headache management.

Rains JC, Poceta JS.

Center for Sleep Evaluation, Elliot Hospital, Manchester, NH 03103, USA.

Review of epidemiological and clinical studies suggests that sleep disorders are disproportionately observed in specific headache diagnoses (eg, migraine, tension-type, cluster) and other nonspecific headache patterns (ie, chronic daily headache, "awakening" or morning headache). Interestingly, the sleep disorders associated with headache are of varied types, including obstructive sleep apnea (OSA), periodic limb movement disorder, circadian rhythm disorder, insomnia, and hypersomnia. Headache, particularly morning headache and chronic headache, may be consequent to, or aggravated by, a sleep disorder, and management of the sleep disorder may improve or resolve the headache. Sleep-disordered breathing is the best example of this relationship. Insomnia is the sleep disorder most often cited by clinical headache populations. DEPRESSION AND ANXIETY ARE COMORBID WITH BOTH HEADACHE AND SLEEP DISORDERS (ESPECIALLY INSOMNIA) AND CONSIDERATION OF THE FULL HEADACHE-SLEEP-AFFECTIVE SYMPTOM CONSTELLATION MAY YIELD OPPORTUNITIES TO MAXIMIZE TREATMENT. This paper reviews the comorbidity of headache and sleep disorders (including coexisting psychiatric symptoms where available). Clinical implications for headache evaluation are presented. Sleep screening strategies conducive to headache practice are described. Consideration of the spectrum of sleep-disordered breathing is encouraged in the headache population, including awareness of potential upper airway resistance syndrome in headache patients lacking traditional risk factors for OSA. Pharmacologic and behavioral sleep regulation strategies are offered that are also compatible with treatment of primary headache.

Publication Types:
Review
PMID: 17040332 [PubMed]
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Cephalalgia. 2008 Feb;28(2):139-43.  
Refractory chronic headache associated with obstructive sleep apnoea syndrome.

Mitsikostas DD, Vikelis M, Viskos A.

Athens Naval Hospital, Neurology Department, Athens, Greece. dmitsikostas@ath.forthnet.gr

The aim was to investigate the comorbidity of chronic refractory headache with obstructive sleep apnoea syndrome (OSAs). Seventy-two patients (51 women and 21 men) with chronic and refractory headaches, whose headache occurred during sleep or whose sleep was accompanied by snoring, were submitted to polysomnography. Patients diagnosed with OSAs (respiratory disturbance index > 10) began continuous positive airway pressure (C-PAP) treatment and were followed up for >or= 6 months. Twenty-one cases of OSAs were identified (29.2% of the total investigated, 13.7% of the women and 66.6% of the men). Headaches were classified into several headache disorders, medication overuse headache and cluster headache being the most prevalent (nine and six of the 21 cases, respectively). In one case (1.4% of the total sample, 4.7% of all the men), the criteria for hypnic headache were fulfilled. Multivariate regression analysis revealed that age, male gender and body mass index were associated with OSAs. C-PAP treatment improved both sleep apnoea and headache in only a third of the cases. Patients suffering from chronic refractory headache associated with sleep or snoring, in particular those who are also middle-aged, overweight men, should be considered for polysomnography. C-PAP treatment alone does not seem to improve headache, but further investigation is needed.

PMID: 17999682 [PubMed]