title: Association between insomnia symptoms and hemoglobin A1c level in Japanese men.
abstract: BACKGROUND
  The evidence for an association between insomnia symptoms and blood hemoglobin A(1c) (HbA(1c)) level has been limited and inconclusive. The aim of this study was to assess whether each symptom of initial, middle, and terminal insomnia influences HbA(1c) level in Japanese men.
  
  
  METHODS
  This cross-sectional study examined 1,022 male workers aged 22-69 years with no history of diabetes at a Japanese company's annual health check-up in April 2010. High HbA(1c) was defined as a blood level of HbA(1c) ≥6.0%. Three types of insomnia symptoms (i.e., difficulty in initiating sleep, difficulty in maintaining sleep, and early morning awakening) from the previous month were assessed by 3 responses (i.e., lasting more than 2 weeks, sometimes, and seldom or never [reference group]).
  
  
  RESULTS
  The overall prevalence of high HbA(1c) was 5.2%. High HbA(1c) was positively and linearly associated with both difficulty in maintaining sleep (P for trend  = .002) and early morning awakening (P for trend  = .007). More specifically, after adjusting for potential confounding factors, high HbA(1c) was significantly associated with difficulty in maintaining sleep lasting more than 2 weeks (adjusted odds ratio, 6.79 [95% confidence interval, 1.86-24.85]) or sometimes (2.33 [1.19-4.55]). High HbA(1c) was also significantly associated with early morning awakening lasting more than 2 weeks (3.96 [1.24-12.59]).
  
  
  CONCLUSIONS
  Insomnia symptoms, particularly difficulty in maintaining sleep and early morning awakening, were found to have a close association with high HbA(1c) in a dose-response relationship.
authors: Department of Hygiene and Public Health, School of Medicine, Teikyo University, Tokyo, Japan. katti@orange.zero.jp
authors: Yuko
authors: Y
authors: Kachi
authors: Mutsuhiro
authors: M
authors: Nakao
authors: Takeaki
authors: T
authors: Takeuchi
authors: Eiji
authors: E
authors: Yano
mesh_terms: D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D007319:Sleep Initiation and Maintenance Disorders / Q000097:blood*; D055815:Young Adult
chemical_list: D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human