title: Nighttime sleep and daytime functioning correlates of the insomnia complaint in young adults.
abstract: The nighttime and daytime correlates of the insomnia complaint (IC) were assessed in an in-class survey on a sample of 1238 first year university students (18.85+/-1.45 years) at the Universidad Autónoma of Madrid, Spain. Evidence was found that the likelihood of complaining of insomnia was increased by perceiving difficulties with initiating and maintaining sleep, reporting low quality of nocturnal sleep, having a long sleep onset latency and having an evening circadian preference. The most strongly related daytime variables to IC being perceived difficulties in concentrating, feelings of irritability and fatigue, and symptoms of anxiety and depression. The data, in addition to confirm those of clinical studies on subjects complaining of insomnia, suggest that having an evening chronotype increases the vulnerability of adolescents and young adults to complain of insomnia.
authors.affiliation: Department of Psychiatry, School of Medicine, Universidad Autónoma de Madrid, 28029 Madrid, Spain.
authors.forename: Julio
authors.initials: J
authors.lastname: Fernández-Mendoza
authors.forename: Antonio
authors.initials: A
authors.lastname: Vela-Bueno
authors.forename: Alexandros N
authors.initials: AN
authors.lastname: Vgontzas
authors.forename: Sara
authors.initials: S
authors.lastname: Olavarrieta-Bernardino
authors.forename: María José
authors.initials: MJ
authors.lastname: Ramos-Platón
authors.forename: Edward O
authors.initials: EO
authors.lastname: Bixler
authors.forename: Juan José
authors.initials: JJ
authors.lastname: De la Cruz-Troca