ORIGINAL ARTICLE Inter-critical and critical excessive daily sleepiness in episodic migraine patients S. Gori • C. Lucchesi • M. R. Maluccio • N. Morelli • M. Maestri • E. Bonanni • L. Murri Received: 7 January 2011 / Accepted: 26 December 2011 Ó Springer-Verlag 2012 Abstract The objective of this study was to determine the relationship between sleepiness and migraine in the intercritical period and to evaluate the time course of critical drowsiness during the attacks. One hundred patients fulfilling IHCD 2nd (2004) criteria for migraine without aura were compared to 100 healthy subjects. Habitual excessive daily sleepiness, evaluated by means of Epworth Sleepiness Scale, was not more frequent in patients with episodic migraine than in controls (12% migraineurs vs. 8% controls, NS). The analysis of critical sleepiness by means of Stanford Sleepiness Scale (SSS) revealed a beginning of sleepiness increase before the attack onset, starting 12 h before, a peak of SSS values at the migraine attack onset and then a gradual decrease to reach baseline values only 12–24 h later. Moreover, patients responding to symptomatic drugs showed a greater and faster decrease of critical sleepiness in comparison with non-responder migraineurs; this finding allows excluding the role of medications in promoting critical somnolence and together with critical drowsiness time-course supports the hypoth- esis that vigilance impairment could be related to migraine pathogenesis. Keywords Migraine without aura Á Excessive daily sleepiness Introduction Excessive Daily Sleepiness (EDS) is defined as the diffi- culty in maintaining a desired level of wakefulness [1]. It affects up to 12% of the general population, with increas- ing prevalence in the elderly [2]. EDS can reduce quality of life, leading to cognitive impairment, mood disorders and increased risk of car accidents. Roth and Roehrs [3] iden- tified four major causes of EDS: primitive sleep disorders, qualitative or quantitative sleep deficiencies, deregulation of the body’s circadian rhythms and drugs, which can increase sleepiness either therapeutically or as a side effect. All these factors can contribute to cause excessive daily sleepiness in migraine patients. The relationship between migraine and excessive daily sleepiness has been studied in a limited number of studies with different results. As far as intercritical EDS concerns, Peres et al. [4] studied 200 patients with chronic or episodic migraine and found that EDS was present in 37% of all migraine patients, and in particular in 32% of episodic and in 39.8% of chronic migraineurs. Barbanti et al. [5] conducted a case-control study on 100 episodic migraine patients compared to 100 age- and sex-matched healthy controls to evaluate EDS in migraine patients. According to this study, EDS was more frequent in migraineurs than in controls (14% vs. 5%) and EDS correlated with migraine disability, sleep problems and anxiety. Seidel et al. [6] analyzed the relationship between quality of sleep, fatigue and daytime sleepiness in migraine patients and healthy subjects, examining also the impact of depression and anxiety. According to this study, fatigue and daytime sleepiness were not increased in migraineurs, whereas quality of sleep was decreased in migraineurs as a consequence of migraine itself. S. Gori (&) Á C. Lucchesi Á M. R. Maluccio Á N. Morelli Á M. Maestri Á E. Bonanni Á L. Murri Department of Neurosciences, Centre for Headache and Adaptive Disorder, Institute of Neurology, University of Pisa, Via Roma 67, 56126 Pisa, Italy e-mail: s.gori@med.unipi.it 123 Neurol Sci DOI 10.1007/s10072-011-0924-6