Risk of smoking and metabolic syndrome for incidence of cardiovascular disease--comparison of relative contribution in urban Japanese population: the Suita study.

BACKGROUND

Risk factor clustering, the so-called metabolic syndrome (MetS), is an important risk factor for cardiovascular disease (CVD). Smoking is also an important CVD risk factor with still a high prevalence. However, few previous studies have compared the risk for CVD or the population-attributable fraction (PAF) of smoking, MetS, and both.

METHODS AND RESULTS

The present study was an 11.9-year cohort study of 1,822 men and 2,089 women, aged 40-74 years, selected randomly from an urban general population in Japan. MetS was defined according to the National Cholesterol Education Program on Adult Treatment Panel III (NCEP-ATPIII) guideline modified by the Asian criteria for waist circumference. The prevalence of smoking was 49.5% in men and 11.1% in women, and that of MetS was 19.8% and 23.5%, respectively. In men, the multivariate-adjusted hazard ratio for CVD incidence, compared with non-smoking participants without MetS, was 2.07 (1.26-3.40) in those who smoked, 2.09 (1.08-4.04) in those with MetS, and 3.56 (1.89-6.72) in those with both. In men the PAF for CVD incidence was 21.8% because of smoking, 7.5% because of MetS, and 11.9% because of both.

CONCLUSIONS

Although countermeasures for MetS are important, smoking should continue to be considered an important public health problem and antismoking campaigns should be promoted, especially for men, to prevent CVD.