Healthy lifestyle and preventable death: Findings from the Japan Collaborative Cohort (JACC) Study

Objective. To evaluate the effect of baseline combination of 6 lifestyle factors on all-cause mortality. Methods. A total of 62,106 Japanese men and women aged 40-79 years were followed for 12.5 years on average. Hazard ratios and 95% confidence intervals (CIs) of all-cause mortality in relation to healthy lifestyle factors (not currently smoking, not heavily drinking, walking I h or more per day, sleeping 6.5 to 7.4 h per day, eating green-leafy vegetables almost daily and BMI between 18.5 and 24.9) were calculated from proportional-hazards regression models. We also estimated population-attributable fractions of death to address the impact of potential lifestyle modifications on mortality. Results. Until 2003, 8497 deaths were observed. Age-adjusted HR of all-cause mortality for the group with 6 healthy lifestyle factors was 0.42 (95% CI: 0.32-0.56) among men and 0.49 (0.39-0.60) among women, respectively, compared with the group with 0-2 healthy lifestyle factors. Even at ages 60-79 years, a healthy lifestyle has a major impact on mortality. Had the subjects achieved even a 1-point increment in their lifestyle scores, death rates of 24.7% among men and 18.5% among women could have been reduced. Conclusion. We found an inverse association between baseline combination of 6 healthy lifestyle factors and all-cause mortality as well as its impact on preventable fraction of death. Our results also demonstrated that healthy lifestyle behaviors are important even in old age. (C) 2009 Elsevier Inc. All rights reserved.