Frequency of Laughter and Risk of Metabolic Syndrome Components among Middle-aged Japanese Men and Women
METHODS: A community-based cross-sectional and prospective study was undertaken using data collected from 4,780 (1,786 men and 2,994 women, mean 59 years) in cardiovascular risk surveys for 5 years. We evaluated frequency of laughing out loud by a self-rated questionnaire. The odds ratios (ORs) of prevalence and incidence of metabolic syndrome and its components relative to the “every day” laughter group were calculated using the logistic regression model.
RESULTS: In cross-sectional analyses, the age, sex, and body mass index-adjusted ORs (95%CIs) of diabetes mellitus (n=301), hypertension (n=2,570), dyslipidemia (n=902), and metabolic syndrome (n=436) were 1.25 (0.96-1.64), 1.01 (0.88-1.17), 1.03 (0.87-1.22), and 1.04 (0.82-1.33) for the “1-5 days/week” laughter group and 1.52 (1.09-2.13), 0.99 (0.80-1.21), 1.12 (0.89-1.41), 1.11 (0.80-1.53) for the “less than once a week” laughter group, compared with the “every day” laughter group. In prospective analyses, frequency of laughter was significantly associated with the incidence of diabetes mellitus among women, but not men. The age and body mass index-adjusted ORs (95%CIs) of diabetes mellitus was 1.44 (0.94-2.21) for the “1-5 days/week” laughter group and 2.23 (1.17-4.25) for the “less than once a week” laughter group among women. There were no significant associations of frequency of laughter with incidence of hypertension, dyslipidemia, and metabolic syndrome.
CONCLUSIONS: Frequency of laughter may be associated with diabetes mellitus, but not hypertension and dyslipidemia, among Japanese men and women.