A Comparative Analysis of Lung Cancer Incidence and Tobacco Consumption in Canada, Norway and Sweden: A Population-Based Study.

Risk factors for developing lung cancer include tobacco smoking, exposure to second-hand smoke, radon gas, asbestos and other carcinogens, as well as air pollution and aging. Canada, Norway and Sweden are three Arctic countries that are very similar in socioeconomic status, similar in the social determinants of health and many environmental factors, including current smoking rates. However, lung cancer incidence rates differ significantly among the three countries. Since tobacco smoking is the principal risk factor for developing lung cancer, and there is a long lag time between tobacco consumption and lung cancer incidence at the population average level, a comparative analysis is conducted with historical data available publicly in the three countries to demonstrate how tobacco consumption in the past impacts lung cancer incidence decades late. The analysis shows that lung cancer incidence rates increase proportionally with the increasing tobacco consumption rates with a lag time of 20-30 years. On average, one more cigarette smoked per person per day can increase lung cancer cases by 2 to 5 per 100,000 population.