Sleep disturbances in outpatients with ankylosing spondylitis - A questionnaire study with gender implications

Objective: To study the sleep pattern in ankylosing spondylitis, and to investigate gender differences in sleep, pain, and fatigue. Methods: Forty-three male and 27 female patients with ankylosing spondylitis completed a sleep questionnaire and the results were compared with earlier findings in 3,558 persons randomly selected from the general population. Results: Too little sleep was reported by 80.8% of the female and 50.0% of the male patients, compared to 28.8% and 21.8% respectively in the reference group (p<0.0001). The main reason was pain in the pre-sleep and sleep-periods (p<0.0001). Daytime fatigue was a major problem (p<0.0001). Higher correlation was found between pain and daytime fatigue than between sleep disturbance and daytime fatigue. Conclusion: Sleep disturbance is a significant problem in ankylosing spondylitis. The disturbance is closely related to pain at bedtime and during the night. Gender differences exist in the subjective sleep disturbance, fatigue, and pain.