title: Effect of Daylight on Melatonin and Subjective General Health Factors in Elderly People.
abstract: BACKGROUND
  This paper investigated the effect of daylight on morning and night melatonin, subjective general health using GHQ questionnaire, sleepiness and alertness on elderly who lived in nursing houses.
  
  
  METHODS
  Nineteen nursing home residents participated voluntarily. They exposed to daylight from 9 to 10 a.m. and from 4 to 5 p.m. for 6 wk. The level of melatonin in the morning and at night was measured. General health of all participants was evaluated using General Health Questionnaire (GHQ) as well.
  
  
  RESULTS
  Daylight exposure significantly affected morning melatonin from 25.39 pg/ml to 59.77 pg/ml (P=0.001) and night melatonin were changed from 40.30pg/ml to 34.41pg/ml (P=0.081). Mean score of general health changed 36.31 to 29.89 (P=0.003). Karolinska Sleepiness Scale (KSS) and Visual Analogue Scale (VAS) showed increase sleepiness and decrease alertness from 3:00 to 7:00 a.m. Sleepiness decreased and alertness increased during 1:00 p.m. and 20:00 p.m.
  
  
  CONCLUSIONS
  Daylight exposure could delay sleep phase and correction of circadian rhythm in elderly. Anxiety and insomnia could be improved with daylight exposure. It suggests that elders should be exposed to scheduled daylight in morning and evening for prevention and improvement of mental disorders. Adequate light should be provided for elder's homes and nursing house.
authors.affiliation: Dept. of Ergonomics, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Zohre
authors.initials: Z
authors.lastname: Karami
authors.affiliation: Dept. of Ergonomics, School of Public Health AND Research Center for Health Sciences, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Rostam
authors.initials: R
authors.lastname: Golmohammadi
authors.affiliation: Dept. of Psychiatry, School of Medicine and Research Center for Behavioral Disorders and Substance Abuse, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Heidaripahlavian
authors.affiliation: Dept. of Epidemiology and Biostatistics, School of Public Health and Research Center for Health Sciences, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Jalal
authors.initials: J
authors.lastname: Poorolajal
authors.affiliation: Dept. of Ergonomics, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Rashid
authors.initials: R
authors.lastname: Heidarimoghadam
keywords: Circadian rhythm; Daylight; Elderly; Health; Iran; Melatonin