Once a symbol of high society, cigarettes are today more prevalent among poorer U.S. populations, particularly in impoverished counties of the South. An analysis led by the University of Washington's Institute for Health Metrics and Evaluation shows that while the rate of adult U.S. smokers has shrunk by 27 percent since 1997, among the poor it has declined just 15 percent. In some areas, it has not declined at all. 

The findings suggest that public health officials should focus antismoking campaigns on the poor and working class, the authors wrote.