The North Karelia Project: The Spark That Ignited the Flame!

Contribution of smoking change to 45-year trend in prevalence of chronic bronchitis in Finland

AIMS

Tobacco smoking has been identified as the most important risk factor of chronic bronchitis. The aim of this study was to assess the contribution of smoking to the trends in prevalence of chronic bronchitis among men and women in Finland.

METHODS

For this purpose, we analysed questionnaires included in national FINRISK and FinHealth studies conducted between 1972 and 2017 in 5-year intervals. A total of 26,475 men and 28,684 women aged 30-59 years were included in the analysis. In addition to smoking, age and socioeconomic status were used as risk factors in the logistic regression model.

RESULTS

Smoking in Finland has declined from 51% to 23% in men between 1972 and 2017. In women, it increased from 11% in 1972 to 23% in 2002, with a following decrease to 16% in 2017. The prevalence of chronic bronchitis has generally followed the trend of smoking. The population attributable risk was 60% in men and 49% in women. A decrease in chronic bronchitis was observed in male never-smokers.

CONCLUSIONS

Smoking is currently declining in Finland in both men and women. As result, the prevalence of chronic bronchitis is declining and it is approaching baseline independent of smoking. The decrease in never-smokers has yet to be explained.

The North Karelia Project: Prevention of Cardiovascular Disease in Finland Through Population-Based Lifestyle Interventions

The North Karelia Project was started in 1972 as a response to the high cardiovascular mortality among men in North Karelia, Finland's easternmost province. Prevalent cardiovascular disease risk factors in the province included elevated serum cholesterol, hypertension, and smoking. Through a sociobehavioral framework utilizing community-based interventions and national-level policy changes and legislation, the project targeted lifestyle changes as a means to alleviate cardiovascular disease risk factors. Diet recommendations included minimizing the use of saturated fats and decreasing salt intake. Another target of the project was to reduce the prevalence of smoking. As a result of the lifestyle interventions that continued beyond the initial 5 years of the project and then expanded to all of Finland, there were significant reductions in serum cholesterol levels, hypertension, smoking prevalence, and cardiovascular disease mortality. The North Karelia Project demonstrates that successful population-based lifestyle interventions serve as a sustainable public health solution to the growing chronic disease burden.

Why Did North Karelia-Finland Work?: Is it Transferrable?

Successful prevention of cardiovascular diseases in the North Karelia Project and Finland has drawn international attention, particularly as cardiovascular diseases and more generally noncommunicable diseases have become the leading cause of premature mortality in the world. The questions have often been asked about what were the main reasons for success and whether or not the experience could be transferred elsewhere. The main lesson is that the possibilities and potential of cardiovascular prevention are great. The principles of population-based prevention are universal and are expressed in the strategies of World Health Organization. But, the practical implementation of the preventive work must be tailored to local cultural, social, and administrative (political) situations. This paper discusses many elements of the work in North Karelia and Finland that were likely important for success.