Headache characteristics in obstructive sleep apnea syndrome and insomnia

Objectives - To determine headache characteristics in the obstructive sleep apnea syndrome (OSAS) and in insomnia. Patients and methods- Fifty-six OSAS patients and 50 insomnia patients were assessed in the same time period. Patients in both groups underwent an accurate interview to investigate headache occurrence and its characteristics. Results - Headache was reported by 49% of OSAS patients and 48% of insomnia patients. In OSAS patients headache had most frequently a tension-type pattern. Headache occurred on awakening in 74% of OSAS patients, more frequently than in insomnia patients (40%) (chi(2); P < 0.04). The occurrence of morning headache appears to be significantly correlated with nocturnal oxygen and OSAS severity. Conclusion - Headache is a common finding in both OSAS and insomnia patients. Because morning headache seems to be more specific for OSAS than insomnia, and in OSAS its occurrence seems to be associated with disease severity, we hypothesize the involvement of certain pathogenic mechanisms associated with OSAS.