title: Inquiring about insomnia may facilitate diagnosis of depression in the primary care setting.
abstract: OBJECTIVE
  Depression is often undiagnosed in primary care. Asking about sleep status is much easier than asking about mood. This study was conducted to examine the relation between insomnia and depression.
  
  
  METHODS
  New patients aged 35-64 years were recruited from internal medicine clinics in Japan. Self-administered questionnaires were employed. Depression was evaluated by the Zung Self-Rating Depression Scale and the Profile of Mood States. Sleep status was investigated using the Pittsburgh Sleep Quality Index. Likelihood ratios of insomnia for depression were calculated. To assess the relation between insomnia and depression independent of confounding factors, adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated using multiple logistic regression analyses.
  
  
  RESULTS
  Among 598 subjects, 153 (25.6%) were assessed as having depression. 'Very bad sleep quality, with difficulty falling asleep within 30 min ≥3 times/week' showed a positive likelihood ratio of 20.36 (95%CI, 2.53-164) while 'not very good sleep quality' had a negative likelihood ratio of 0.32 (95%CI, 0.14-0.72). Adjusted for sex, age, underlying diseases, major life events, lifestyle habits, and relationship problems, significant OR for depression were observed for 'difficulty falling asleep within 30 min ≥3 times/week' (OR, 2.53; 95%CI, 1.07-5.98), 'waking up in the middle of the night or early morning ≥3 times/week' (OR, 3.09; 95%CI, 1.58-6.05), and 'fairly bad sleep quality' (OR, 3.65; 95%CI, 1.34-9.96).
  
  
  CONCLUSIONS
  Inquiring about the weekly frequency of difficulty 'falling asleep within 30 min,' 'waking up in the middle of the night or early morning,' and 'sleep quality' may help to diagnose depression.
authors.affiliation: Department of Neuropsychiatry, Kurume University School of Medicine, Fukuoka, Japan.|Department of Environmental Medicine, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Megumi
authors.initials: M
authors.lastname: Fujieda
authors.affiliation: Mental Health and Welfare Center of Shizuoka Prefectural Government, Shizuoka, Japan.
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Uchida
authors.affiliation: Fuji Medical Association, Shizuoka, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Ikebe
authors.affiliation: Fuji Medical Association, Shizuoka, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Kimura
authors.affiliation: Fuji Medical Association, Shizuoka, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Kimura
authors.affiliation: Fuji Medical Association, Shizuoka, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Mental Health and Welfare Center of Shizuoka Prefectural Government, Shizuoka, Japan.
authors.forename: Hisako
authors.initials: H
authors.lastname: Sakamoto
authors.affiliation: Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Teruaki
authors.initials: T
authors.lastname: Matsumoto
authors.affiliation: Department of Neuropsychiatry, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Naohisa
authors.initials: N
authors.lastname: Uchimura
mesh_terms: D000328:Adult; D003863:Depression / Q000150:complications / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011320:Primary Health Care / Q000379:methods*; D011569:Psychiatric Status Rating Scales; D007319:Sleep Initiation and Maintenance Disorders / Q000150:complications / Q000453:epidemiology*
keywords: epidemiology; internal medicine; middle-aged Japanese; sleep disorder; working generation