[1] Democritus Univ Thrace, Sch Med, Dept Otorhinolaryngol, Alexandroupolis, Greece
[2] Democritus Univ Thrace, Sch Med, Dept Psychiat, Alexandroupolis, Greece
[3] Ghent Univ Hosp, Dept Otorhinolaryngol, Upper Airway Res Lab, Ghent, Belgium
[4] Democritus Univ Thrace, Sch Med, Dept Stat, Alexandroupolis, Greece