Introduction:
Magnitude of impact of healthy lifestyle behaviors and education level on cardiovascular mortality is uncertain.
Hypothesis:
Impact of education on cardiovascular mortality is explained mostly by lifestyle behaviors
Methods:
The survey cohort was a total of 42,647 subjects (18,442 men and 24,205 women) aged 40-79 years with satisfactory information from 1988 to 1990, and followed up until the end of 2009. Education levels were sub-grouped into higher education (last school age of ≥16 years old) and lower education (<16). We defined the healthy lifestyle score (fruits ≥1/day, fish ≥1/day, milk almost every day, exercise ≥5h/week and/or walking ≥0.5h/day, BMI 21-25kg/m2, ethanol intake <46.0g/day, non-smoker, and sleep 5.5-7.5h/day, ranging 0 to 8), and calculated multivariable hazard ratios (HRs) and 95% confidence intervals (95% CIs) to determine the magnitude of impacts of healthy lifestyle behaviors and education level on cardiovascular mortality with persons who have lower education and 0-3 lifestyle score category as reference. Population attributable fraction (PAF) of lifestyle behaviors on cardiovascular mortality stratified by education level were also calculated.
Results:
During the 19.3 median years of follow-up, there were 8,314 total deaths and 2,377 CVD deaths. Compared with persons with lower education and 0-3 healthy lifestyle score category, those with lower education and 7-8 healthy lifestyles score category and those with higher education and 7-8 healthy lifestyle score category showed lower risk of mortality from total CVD. The respective multivariable-adjusted HRs (95% CI) were 0.37 (0.28-0.48) for those with lower education and 7-8 lifestyle score category, and 0.37 (0.30-0.46) for those with higher education and 7-8 lifestyle score category in total men and women, 0.25 (0.14-0.44) and 0.43 (0.31-0.59), respectively, for men, and 0.43 (0.31-0.60) and 0.36 (0.27-0.49), respectively, for women. PAF of CVD mortality for those who were not in the category of 7-8 lifestyle behavior were 40.1% in higher education group and 68.5% in lower education.
Conclusions:
More than 50% of risk reduction of cardiovascular mortality for those who have 7-8 healthy lifestyle score category compared to those who have 0-3 healthy lifestyles were found irrespective of education level which suggests large part of impact of education on cardiovascular mortality is explained by lifestyle behaviors.