Objectives: To investigate associations between total lifestyles and levels of leukocyte DNA damage in healthy Japanese workers.
Methods: Eight health practices were investigated in 118 Japanese hard-metal workers by questionnaire in Osaka, Japan, in July 2004. Peripheral leukocyte DNA damage levels, as expressed by comet parameters, were determined using an alkaline comet assay.
Results: After crediting one point to each of the health practices and accumulating them into a health practice index (HPI: 0-8 points), subjects with poor health practices (HPI = 0-3 points) showed a significantly higher tail moment than those with moderate (HPI = 4, 5 points) or good health practices (HPI = 6-8 points) (P < 0.01). Risk estimates for tail moment above the 75th percentile showed that, compared to those with good health practices, subjects with moderate health practices had an odds ratio of 1.76 (95% CI: 0.52, 5.91), and those with poor health practices had an odds ratio of 6.75 (95% CI: 1.80, 25.27) (P(trend) < 0.01). Multiple regression analysis showed that HPI was a significant predictor of the decreased tail moment (P < 0.01).
Conclusion: Poor lifestyles demonstrate a cumulative association with leukocyte DNA damage in these Japanese hard-metal workers.