[Sleep disorders in patients with medication-overuse headache].

Objective: To analyze complaints about sleep disorders and assess the incidence of various sleep disorders, using relevant scales, in patients with medication-overuse headache (MOH) in comparison with patients without MOH.

Material and methods: The prospective case-control study included 171 patients, aged 18 years and older, with MOH (main group), and173 patients with primary headaches without MOH (control group). A neurologist conducted an initial examination and professional interview before the start of treatment. To diagnose sleep disorders, the International Classification of Sleep Disorders (3rd edition, 2014) was used. Additionally, an assessment was made using the Insomnia Severity Index Scale, the Epworth Sleepiness Scale (ESS) and the Lausanne Obstructive Sleep Apnea Syndrome Scale (NoSAS).

Results: Statistically significant differences were revealed in the prevalence of the following complaints about sleep disorders in patients with MOH: lack of sleep (51.5%), frequent awakenings during sleep (43.3%), discomfort in legs before falling asleep or at rest in the evening (37.4%). Difficulties falling asleep occurred equally often in both patients with MOH (43.9%) and without MOH (37.0%), as well as daytime sleepiness (40.4% vs 36.4%) and the presence of snoring (13% of patients in each group). Patients with MOH were significantly more likely to suffer from chronic insomnia (60.2% and 47.4%, respectively, p=0.02; OR 1.7; 95% CI 1.1-2.6) and restless legs syndrome (37.4% and 22.0%, respectively, p=0.002; OR 2.1; 95% CI 1.3-3.4). The incidence of hypersomnia and obstructive sleep apnea syndrome did not have statistically significant differences.

Conclusion: Patients with MOH compared to patients without MOH have a significantly higher incidence of main complaints of sleep disorders, chronic insomnia and restless legs syndrome, which indicates the importance of sleep disorders in the pathogenesis of medication-overuse headaches and requires timely diagnosis and treatment to prevent the progression of both headaches and sleep disorders.