People who use both e-cigarettes and cigarettes are less likely to quit

People who use both e-cigarettes and cigarettes are less likely to quit smoking than those who only smoke or smoke, according to a new study. Over time, many of these “dual users” are likely to return to smoking cigarettes, undermining the idea that e-cigarettes can be a viable alternative to smoking cessation.

The new study, led by Josef Hamoud of the University Hospital of Göttingen in Germany, found that switching to vaping while still smoking rarely leads to smoking cessation. The researchers argue that their findings suggest that starting vaping while continuing to smoke is likely ineffective in helping people quit smoking.

The research, carried out by scientists from Germany, the USA and Denmark, was led by Josef Hamoud from the University Medical Center Göttingen.

This study is a systematic review and meta-analysis. This means that the researchers evaluated all available studies on people who use both e-cigarettes and cigarettes and combined the data into a single study.

“Vaping is widespread among youth and adults worldwide. With e-cigarettes widely marketed as a healthier alternative to traditional smoking, they are becoming increasingly popular among people who want to quit smoking. Some people consume them in addition to their traditional cigarettes and classify them as dual users.” said Mr Hamoud. “We still don’t know much about the long-term health effects of vaping. However, there are already credible studies suggesting that dual use may actually be more harmful than traditional smoking.”

This comprehensive review summarizes findings from 16 individual studies that examine the behavior of dual users—those who both smoke cigarettes and smoke e-cigarettes—and their trajectories over time in quitting, transitioning to vaping exclusively, and vaping Investigate return to smoking or maintenance of dual smoking.

The analysis includes data from up to 9,337 people, of which 2,432 are identified as dual users. When the researchers compared dual smokers with those who either smoked cigarettes exclusively or smoked only vapor, they found that dual smokers were less likely to quit smoking completely.

Over time, the analysis found that a significant number of dual users returned to traditional cigarette smoking. The statistics are striking; Only 3% of dual users give up completely within four to eight months, and after eight to 16 months the figure drops to just 5%. After 16 to 24 months this value increases to 13%, and after 24 to 48 months it is 24%.

In a convincing analysis of consumption behavior over time, it was found that 30% of dual users only switched to cigarette consumption within the first four to eight months. This trend continued to intensify significantly, with 47% switching between eight and 16 months, 58% between 16 and 24 months, and a still impressive 55% after 24 to 48 months.

When we combine those who continued to use both e-cigarettes and cigarettes with those who switched to smoking entirely, the overall proportion of cigarette users varied from a staggering 90% to 63%. The study also shows that in the medium term (eight to 16 months), 38% of dual users were still using both e-cigarettes and cigarettes.

“This cannot be viewed as a simple ‘transitional state’ but rather as a risk of prolonged dual exposure.” Mr Hamoud said.

He continued: “Given these results, we believe that dual consumption may prove to be a major barrier to smoking abstinence and that this practice should not be recommended for the treatment of nicotine addiction. “In addition, while the long-term health effects of e-cigarettes require further study, the dual exposure to large amounts of nicotine and toxins from both traditional cigarettes and e-cigarettes is a major public health concern.”

According to the researchers, by combining several studies, each using slightly different methodology, it was impossible to classify the different forms of dual use, such as people who primarily smoke but occasionally use e-cigarette products.

Mr Hamoud added: “While it has been argued that heavy smokers may benefit from dual use by reducing their daily cigarette consumption, the high nicotine content of e-cigarettes increases the risk of ongoing nicotine addiction. Future studies need to further stratify dual-use groups to examine health effects over time.”

“We know that vaping is commonplace and that many people use e-cigarettes alongside cigarettes, often in the hope of cutting down on smoking or quitting the habit. This large study looked at all the existing evidence on dual users and showed that it is not a stepping stone to quitting for most people.” said Dr. Filippos Filippidis, chair of the European Respiratory Society Tobacco Control Committee, lecturer in public health at Imperial College London, UK, and was not involved in the research.

“Nicotine in e-cigarettes is highly addictive, so we must do everything we can to discourage non-smokers from taking up e-cigarettes. E-cigarettes may play a role in smoking cessation for some people, but we need to ensure that appropriate support is freely available to help people quit, as it is clear that many end up becoming dual users of smoking cessation attempts can actually undermine.”

Magazine reference:

1. Josef Hamoud, Reiner Hanewinkel, Stefan Andreas. A systematic review examining the effects of dual use of e-cigarettes and traditional cigarettes on smoking cessation. ERJ Open Research, 2024; DOI: 10.1183/23120541.00902-2024