Smoking increases CHD risk
When the Seven Countries Study started in 1958 the prevalence of smokers was very high and ranged from 44% in Belgrade professors in Serbia to 78% in fishermen from Ushibuka in Japan. The 10-year follow-up data showed that smoking was associated with a higher risk of CHD mortality in countries where there were enough events for analysis and the strongest associations were observed in northern Europe where CHD was highest. An analysis using the 25-year CHD mortality data showed similar results.
Smoking a long-term predictor of CVD
The Finnish cohorts showed that the relative risk of CHD mortality among cigarette smokers compared to non-smokers decreased the longer the follow-up, but the excess CHD risk remained significant after 35 years of follow-up. The 40-year data from the Zutphen Study showed that cigarette smokers at entry had a 59% higher CHD and a 66% higher CVD mortality risk compared to non-smokers. The duration, as well as the intensity of smoking, was also independently predictive of CVD mortality.