Dual use of e-cigarettes and e-cigarettes makes smoking cessation difficult

People who use both e-cigarettes and cigarettes are less likely to quit smoking than people who smoke only or only smoke e-cigarettes, according to a study published today (Wednesday). ERJ Open Research.

Instead, research suggests that over time, most of these “dual users” tend to only smoke cigarettes.

The researchers say their findings suggest that starting vaping while continuing to smoke is unlikely to help people quit smoking.

The study, conducted by researchers from Germany, the USA and Denmark, was authored by Josef Hamoud from the University Medical Center Göttingen. It is a systematic review and meta-analysis, meaning the researchers reviewed all existing research on people who use both e-cigarettes and cigarettes and combined the data into one study.

E-cigarettes are widespread among teenagers 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.

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.”

Josef Hamoud from the University Medical Center Göttingen, Germany

The review summarizes 16 individual studies that address the question of whether groups of dual users quit smoking, switched to vaping only, switched to smoking only, or continued dual use over time. Data from up to 9,337 people are included in the analyses, including 2,432 dual users.

When researchers compared dual users with people who only smoked cigarettes or only smoked e-cigarettes, they found that dual users were less likely to quit smoking altogether. Over time, the analysis found that the majority of dual users returned to smoking traditional cigarettes.

The proportion of dual users who quit completely was 3% over four to eight months, 5% after eight to 16 months, 13% after 16 to 24 months, and 24% after 24 to 48 months. This compares to 6%, 7%, 17% and 25%, respectively, over the same period for people who only smoke, and 8%, 19%, 26% and 35%, respectively, for people who only vape.

Over a period of four to eight months, 30% of dual users switched to cigarettes exclusively. Between eight and 16 months, 47% of dual users switched to cigarettes exclusively. Between 16 and 24 months the proportion was 58% and after 24 to 48 months it was 55%.

Most dual users continued to use cigarettes across all time periods. Combining those who continued to dual use with those who switched to smoking exclusively, the overall proportion of cigarette users ranged from 90% to 63%.

The researchers also point out that in the medium term (eight to 16 months), 38% of dual users still used 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, the long-term health effects of e-cigarettes need to be studied. “In addition, the double exposure to large amounts of nicotine and toxins from both traditional cigarettes and e-cigarettes represents a major public health problem.”

The researchers say that by combining multiple studies, each with a slightly different approach, it is not possible to categorize different types of dual-use types, such as people who smoke primarily but smoke occasionally.

Mr Hamoud added: “While it may have been argued that heavy smokers could 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.

Dr. Filippos Filippidis is Chair of the Tobacco Control Committee of the European Respiratory Society, Lecturer in Public Health at Imperial College London, UK, and was not involved in the research. He said: “We know that vaping is commonplace and that many people use both e-cigarettes and 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 drug users and showed that it is not a stepping stone to quitting for most people.”

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