title: Somatic symptoms and psychological characteristics associated with insomnia in postmenopausal women.
abstract: OBJECTIVE
  The aim of the study was to assess the association of sleep disturbance with psychological characteristics, somatic symptoms and previously identified risk factors.
  
  
  METHODS
  Data were from 148,938 postmenopausal women enrolled in The Women's Health Initiative who provided cross-sectional information about psychological characteristics, somatic symptoms and the character of their sleep. Overall sleep quality was based on the Women's Health Initiative Insomnia Rating Scale (WHI IRS), a measure that assessed five types of sleep disturbance.
  
  
  RESULTS
  Three factors accounted for nearly 20% of the variation in the WHI IRS: a scale for somatic symptoms, daytime restlessness and either depression or emotional well-being. Other independently associated factors were night sweats, pain and worry about expressing anger. Several factors that had been linked to sleep disturbance in other studies were found to have at most a weak independent association in this analysis. These included income, education, marital status, activity level, obesity level, hot flashes, coffee drinking and smoking.
  
  
  CONCLUSIONS
  Factors strongly associated with sleep disturbance in this study deserve further evaluation to determine the reasons for the association and whether the associations suggest possible treatments for sleep disturbance.
authors.affiliation: Department of Medicine, University of Utah, Salt Lake City, UT 84112, USA. hartzarthur@gmail.com
authors.forename: Arthur
authors.initials: A
authors.lastname: Hartz
authors.forename: John Jacob
authors.initials: JJ
authors.lastname: Ross
authors.forename: Russell
authors.initials: R
authors.lastname: Noyes
authors.forename: Paula
authors.initials: P
authors.lastname: Williams
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D006304:Health Status; D006801:Humans; D008593:Menopause / Q000502:physiology / Q000523:psychology; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D007319:Sleep Initiation and Maintenance Disorders / Q000503:physiopathology / Q000523:psychology*