title: Laughter is the Best Medicine? A Cross-Sectional Study of Cardiovascular Disease Among Older Japanese Adults.
abstract: BACKGROUND
  We sought to evaluate the associations between frequency of daily laughter with heart disease and stroke among community-dwelling older Japanese women and men.
  
  
  METHODS
  We analyzed cross-sectional data in 20 934 individuals (10 206 men and 10 728 women) aged 65 years or older, who participated in the Japan Gerontological Evaluation Study in 2013. In the mail-in survey, participants provided information on daily frequency of laughter, as well as body mass index, demographic and lifestyle factors, and diagnoses of cardiovascular disease, hyperlipidemia, hypertension, and depression.
  
  
  RESULTS
  Even after adjustment for hyperlipidemia, hypertension, depression, body mass index, and other risk factors, the prevalence of heart diseases among those who never or almost never laughed was 1.21 (95% CI, -1.03-1.41) times higher than those who reported laughing every day. The adjusted prevalence ratio for stroke was 1.60 (95% CI, 1.24-2.06).
  
  
  CONCLUSIONS
  Daily frequency of laughter is associated with lower prevalence of cardiovascular diseases. The association could not be explained by confounding factors, such as depressive symptoms.
authors.affiliation: Faculty of Medicine, the University of Tokyo.
authors.forename: Kei
authors.initials: K
authors.lastname: Hayashi
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kawachi
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ohira
authors.forename: Katsunori
authors.initials: K
authors.lastname: Kondo
authors.forename: Kokoro
authors.initials: K
authors.lastname: Shirai
authors.forename: Naoki
authors.initials: N
authors.lastname: Kondo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006331:Heart Diseases / Q000453:epidemiology*; D006801:Humans; D057187:Independent Living; D007564:Japan / Q000453:epidemiology; D007845:Laughter; D008297:Male; D015995:Prevalence; D012306:Risk; D020521:Stroke / Q000453:epidemiology*