Migration, marital status and smoking as risk determinants of cancer

To study the importance of migration to urban area, marital status and smoking as risk factors in cancer, a cohort of 4,475 Finnish men was followed up for the occurrence of cancer during the period 1964-1980. Of particular interest was the interaction of migration or marital status with smoking. For cancers at all sites, not married urbanized smoking men had the greatest risk, followed by not married native urban smokers. This pattern was mainly due to high risk of cancers of the lung and larynx among the urbanized men, with a risk peak among urbanized not married smokers. The pattern persisted even when the amount smoked was allowed for. The importance in lung cancer epidemiology of vitamin A deficiency, occupation and psychosocial stress was discussed, and some support was found for the role of psychosocial stress in both the migration and the marital status factors.