Cancer has been the second most frequent cause of death in Sweden and in other developed countries for most of the 20th century, and today accounts for about 25 per cent of all mortality. While the trend in overall cancer mortality has been increasing among men, the picture is less clear regarding women. In addition, most of the knowledge about the relationship between tobacco smoking - one of the most important among potentially preventable causes of human cancer - and cancer has been generated in studies involving men only. Recently some studies have suggested that female smokers are more susceptible than male smokers to the carcinogenic effects of tobacco smoke. In the present series of investigations, various aspects of cancer among Swedish women were studied and compared with those of Swedish men. This was achieved through the use of official statistics regarding cancer incidence, cancer mortality and smoking prevalence together with data from a large, population-based questionnaire on smoking habits in Sweden from 1963.
Among men, overall cancer mortality increased between 1931 and 1992, while among women there was a slight decrease. Owing to uncertainties regarding the impact of improvements in diagnostic accuracy the results must be interpreted with some caution. Smoking prevalence was at a high level for men born around the turn of the century, remained high, but started to decrease for men born towards the middle of the century. Among women born around 1900 smoking prevalence was low, but increased steadily for those born later. Lung cancer mortality trends closely followed the pattern of smoking prevalence, with stable rates among men and successively increasing rates among women.
Regarding the risk of getting different types of cancer among women, current smokers ran a higher risk than never regular smokers of getting cancer of the lung, upper aerodigestive sites, pancreas, bladder, cervix, organs of the urinary tract other than kidney and bladder, and all cancers combined. No substantial difference in dose-response gradient regarding smoking-related cancers other than lung cancer was found between male and female smokers. Furthermore, any differences in lung cancer dose-response gradient between male and female smokers are probably small.
Finally, there were only small differences in overall cancer risk and risk of smoking-related cancers between different socio-economic groups in Sweden were the case. Farmers were the notable exception, running a lower risk of getting in particularly smoking-related cancers as compared to blue-collar workers. However, adjusting for smoking habits in 1963, led to decreased differences, and farmers did no longer displayed lower risk.
Linköping: Tema, Linköpings universitet , 1998. , 50 p.
1998-05-08, Planck, Fysikhuset, Campus Valla, Linköpings Universitet, Linköping, 10:00 (Swedish)