Variations in risks from smoking between high-income, middle-income, and low-income countries

Tobacco use is a major risk factor for cardiovascular and respiratory diseases, over 20 different types or subtypes of cancer, and many other health conditions 1. 

In this study, the researchers explored the variation in risk from current smoking compared with never smoking across different countries.

Data from 134 909 participants from 21 countries was analysed as part of the Prospective Urban Rural Epidemiology (PURE) cohort study, the INTERHEART case-control study and the INTERSTROKE case-control study. 

Findings

• The risks of tobacco-related diseases from current smoking are higher in higher-income countries than in middle-income countries and lower-income countries. 
• The levels of nicotine and toxicants were higher in cigarettes from higher-income countries  than in those from middle-income countries. (PURE study)
• In studies done in higher-income countries, the risks of all-cause mortality were about 2–3 times higher in current than in never smokers.By contrast, studies in middle-income countries and lower-income countries have reported lower hazards for all-cause mortality than those seen in higher-income countries.

The authors conclude that there are there are significant differences in risks associated with tobacco use among individuals in different country income groups, which the authors suggest may be linked with higher exposure of tobacco-derived toxicants among smokers in higher-income countries.