The relationship between headaches and sleep disturbances.

The relationship between headaches and sleep disturbances is complex and difficult to analyze. Both symptoms may have causal relations, or may be associated in the same patient with mutual reinforcements. We studied 25 patients presenting with morning or nocturnal headaches. Standard headache diagnosis and polysomnography were performed. After polysomnography, the diagnoses were reevaluated. The main headache entities were cluster, chronic paroxysmal hemicrania, migraine, tension, combined headache, and chronic substance abuse headache. For each group, headache, sleep data, and changes in diagnosis are discussed. The diagnosis was changed in 13 patients; the final diagnoses were periodic movements of sleep, fibromyalgia syndrome, and obstructive sleep apnea. The diagnoses of cluster headache and chronic paroxysmal hemicrania were not modified by polysomnography. The migraine and tension headache groups had a relative male preponderance, and the diagnosis was changed in approximately half of the patients. This was also observed in combined headaches. Patients who had chronic substance abuse headaches had mainly insomnia, which in some cases, was relieved by stopping medication. Data were also analyzed in terms of simple models linking headache and sleep disturbances. Such an approach allowed the identification of several modes of mutual interaction. In summary, morning or nocturnal headaches are frequent indicators of a sleep disturbance and their presence might justify polysomnography, and the use of simple clinical models may be useful for understanding the complex relationship between headache and sleep.