Research News

Smokers are more likely to quit as smoking prevalence decreases, study shows

BMJ 2015; 350 doi: (Published 25 June 2015) Cite this as: BMJ 2015;350:h3447
  1. Susan Mayor
  1. 1London

Smokers are more likely to reduce their smoking and try to quit as the proportion of people who smoke in a population decreases, an international study has found,1 suggesting that current smoking reduction strategies are working and questioning claims that electronic (e) cigarettes provide a harm reduction strategy for smokers who are unable to quit.

Researchers analysed survey data on tobacco covering 18 years in the United States (1992-93 to 2010-11) and six years (2006 to 2012) in 31 European countries. The results, reported in Tobacco Control, showed that the number of people trying to quit smoking increased by 0.55% (standard error ±0.07%) with each 1% decrease in smoking prevalence in the US (P<0.001) and that it remained stable in Europe (P=0.53).1

Further analysis showed that the percentage of US smokers who stopped smoking increased by 1.13% (SE ±0.06%) with every 1% drop in the fraction of the population who smoked (P<0.001), and people who continued to smoke had an average of 0.32 (SE ±0.02) fewer cigarettes each day (P<0.001). In Europe the average number of cigarettes smoked each day decreased by 0.22 (SE ±0.05; P<0.001).

These associations were stable at any given prevalence over time in the US, with a reduction of 0.15 (SE ±0.06) cigarettes a day each year (P<0.05).

It has previously been argued that, as smoking prevalence declines, the smokers who remain will include higher proportions of hardcore smokers who are unwilling or unable to quit—a process termed “hardening.” The use of smokeless tobacco and e-cigarettes has been promoted as a strategy to help these hardcore smokers.

“If hardening is occurring, there should be a positive association between smoking prevalence and quitting, with less quitting at lower prevalence,” explained the researchers, led by Stanton Glantz, of the Center for Tobacco Control Research at the University of California, San Francisco, USA. They noted that their study showed the opposite, with a softening in smokers’ openness to quitting. As smoking prevalence has declined over time, attempts to quit have increased in the US and remained stable in the European Union.

“The fact that the smoking population is softening has important implications for public health policy,” said Glantz. “These results suggest that current tobacco control policies have been leading to softening of the smoking population without the need to promote new recreational nicotine products like e-cigarettes.”

Margarete Kulik, also from the Center for Tobacco Control Research, said that the study’s take home message is that current policies—including strong anti-tobacco media, smoke-free legislation, and increased tobacco taxes—have been working.

“We show that there is no real need to distribute e-cigarettes as part of a tobacco policy package because the smoking population is softening,” she concluded, adding, “Tobacco control policies should continue to move the population down these softening curves rather than changing policies to promote new forms of nicotine delivery, especially ones like e-cigarettes that are very appealing to children.”


Cite this as: BMJ 2015;350:h3447


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