title: Risk factors for sudden unexpected death among workers: a nested case-control study in central Japan.
abstract: BACKGROUND; Few studies have focused on sudden death among apparently healthy workers, and the risk factors have not been fully discussed.
  
  
  METHODS
  A nested case-control study was conducted among 164,017 male employees receiving annual medical checkups in Japan. Most recent medical checkup data of 242 sudden death victims (mean age, 48.0 years) were compared with corresponding data of 505 age-, workplace-, and job-type-matched male controls. Odds ratios (ORs) and their 95% confidence intervals (CIs) for each variable were calculated by logistic regression.
  
  
  RESULTS
  OR (95% CI) significantly increased with advancing blood pressure, reaching 6.6 (3.4-13.1) for systolic blood pressure > or =160 mm Hg relative to that <120 mm Hg. Hypo-HDL-cholesterolemia, hyperuricemia, increased aminotransferases, and abnormal urinary findings were associated with the risk in a dose-dependent manner. The presence of arrhythmias and ST-T abnormalities as well as abnormal Q waves on electrocardiograms yielded a 3.5 to 4.8 times greater risk of sudden death. As for lifestyles, heavy smoking was a positive, and light drinking was a negative risk factor. Multivariate analysis revealed that hypertension, proteinuria, glucosuria, arrhythmias, ST-T abnormalities, and light drinking were independent predictors for sudden death.
  
  
  CONCLUSIONS
  These findings suggest that periodic medical checkups can help to predict and prevent employee sudden death.
authors.affiliation: First Department of Internal Medicine, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kondo
authors.forename: T
authors.initials: T
authors.lastname: Kawamura
authors.forename: M
authors.initials: M
authors.lastname: Hirai
authors.forename: A
authors.initials: A
authors.lastname: Tamakoshi
authors.forename: K
authors.initials: K
authors.lastname: Wakai
authors.forename: T
authors.initials: T
authors.lastname: Terazawa
authors.forename: S
authors.initials: S
authors.lastname: Osugi
authors.forename: M
authors.initials: M
authors.lastname: Ohno
authors.forename: N
authors.initials: N
authors.lastname: Okamoto
authors.forename: T
authors.initials: T
authors.lastname: Tsuchida
authors.forename: Y
authors.initials: Y
authors.lastname: Ohno
authors.forename: J
authors.initials: J
authors.lastname: Toyama
mesh_terms: D001794:Blood Pressure; D016022:Case-Control Studies; D002784:Cholesterol / Q000097:blood; D003645:Death, Sudden / Q000453:epidemiology / Q000209:etiology*; D004562:Electrocardiography; D006304:Health Status; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008019:Life Style; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009790:Occupations; D010808:Physical Examination; D012307:Risk Factors
chemical_list: D002784:Cholesterol