Clear The Air News Tobacco Blog Rotating Header Image

Review

E-Cigarettes: Use, Effects on Smoking, Risks, and Policy Implications

Download (PDF, 1.04MB)

The Debate About Electronic Cigarettes: Harm Minimization or the Precautionary Principle

Download (PDF, 106KB)

How will Brexit affect health and health services in the UK?

Download (PDF, 337KB)

Association Between Initial Use of e-Cigarettes and Subsequent Cigarette Smoking Among Adolescents and Young Adults

A Systematic Review and Meta-analysis.

https://www.ncbi.nlm.nih.gov/pubmed?term=Association%20Between%20Initial%20Use%20of%20e-Cigarettes%20and%20Subsequent%20Cigarette%20Smoking%20Among%20Adolescents%20and%20Young%20Adults%3A%20A%20Systematic%20Review%20and%20Meta-analysis.&holding=ucsflib&otool=cdlotool&cmd=search

Abstract

IMPORTANCE:

The public health implications of e-cigarettes depend, in part, on whether e-cigarette use affects the risk of cigarette smoking.

OBJECTIVE:

To perform a systematic review and meta-analysis of longitudinal studies that assessed initial use of e-cigarettes and subsequent cigarette smoking.

DATA SOURCES:

PubMed, EMBASE, Cochrane Library, Web of Science, the 2016 Society for Research on Nicotine and Tobacco 22nd Annual Meeting abstracts, the 2016 Society of Behavioral Medicine 37th Annual Meeting & Scientific Sessions abstracts, and the 2016 National Institutes of Health Tobacco Regulatory Science Program Conference were searched between February 7 and February 17, 2017. The search included indexed terms and text words to capture concepts associated with e-cigarettes and traditional cigarettes in articles published from database inception to the date of the search.

STUDY SELECTION:

Longitudinal studies reporting odds ratios for cigarette smoking initiation associated with ever use of e-cigarettes or past 30-day cigarette smoking associated with past 30-day e-cigarette use. Searches yielded 6959 unique studies, of which 9 met inclusion criteria (comprising 17 389 adolescents and young adults).

DATA EXTRACTION AND SYNTHESIS:

Study quality and risk of bias were assessed using the Newcastle-Ottawa Scale and the Risk of Bias in Non-randomized Studies of Interventions tool, respectively. Data and estimates were pooled using random-effects meta-analysis.

MAIN OUTCOMES AND MEASURES:

Among baseline never cigarette smokers, cigarette smoking initiation between baseline and follow-up. Among baseline non-past 30-day cigarette smokers who were past 30-day e-cigarette users, past 30-day cigarette smoking at follow-up.

RESULTS:

Among 17 389 adolescents and young adults, the ages ranged between 14 and 30 years at baseline, and 56.0% were female. The pooled probabilities of cigarette smoking initiation were 30.4% for baseline ever e-cigarette users and 7.9% for baseline never e-cigarette users. The pooled probabilities of past 30-day cigarette smoking at follow-up were 21.5% for baseline past 30-day e-cigarette users and 4.6% for baseline non-past 30-day e-cigarette users. Adjusting for known demographic, psychosocial, and behavioral risk factors for cigarette smoking, the pooled odds ratio for subsequent cigarette smoking initiation was 3.62 (95% CI, 2.42-5.41) for ever vs never e-cigarette users, and the pooled odds ratio for past 30-day cigarette smoking at follow-up was 4.28 (95% CI, 2.52-7.27) for past 30-day e-cigarette vs non-past 30-day e-cigarette users at baseline. A moderate level of heterogeneity was observed among studies (I2 = 60.1%).

CONCLUSIONS AND RELEVANCE:

e-Cigarette use was associated with greater risk for subsequent cigarette smoking initiation and past 30-day cigarette smoking. Strong e-cigarette regulation could potentially curb use among youth and possibly limit the future population-level burden of cigarette smoking.

Vaping teens more likely to take up regular cigarettes

Adolescents and young adults who try e-cigarettes are more than three times as likely to take up smoking traditional cigarettes as their peers who haven’t tried the devices, a research review suggests.

https://uk.reuters.com/article/us-health-teens-vaping-idUKKBN19H292

E-cigarette use, or vaping, was as least as strong a risk factor for smoking traditional cigarettes as having a parent or sibling who smokes or having a risk-taking and thrill-seeking personality, researchers found.

“E-cigarette use among teens and young adults could increase the future burden of tobacco by creating a new generation of adult smokers who might have otherwise not begun smoking,” said lead study author Samir Soneji of the Dartmouth Institute for Health Policy and Clinical Practice in New Hampshire.

Big tobacco companies, including Altria Group Inc, Lorillard Tobacco Co and Reynolds American Inc, are all developing e-cigarettes. The battery-powered devices feature a glowing tip and a heating element that turns liquid nicotine and other flavorings into a cloud of vapor that users inhale.

Soneji and colleagues analyzed data from nine smaller studies with a total of 17,389 participants ages 14 to 30.

They didn’t examine why many teens and young adults transitioned from vaping to smoking traditional cigarettes, but both options contain nicotine, an addictive drug, Soneji said by email.

The habit of vaping may also make the transition to smoking seem more natural, and teens in particular may gravitate toward friends who smoke once they try vaping, Soneji said.

“To the extent that e-cigarette use mimics the behavior of smoking a cigarette – handling the e-cigarette, the action of puffing, and the inhalation of smoke – it sets the adolescent up for easily transitioning to smoking,” Soneji said. “Like transitioning from driving a Tesla to driving a Chevy.”

Seven studies looked at smoking initiation among more than 8,000 youngsters who had never smoked before. Data pooled from these studies showed that roughly 30 percent of e-cigarette users became smokers, compared with only about 8 percent of people who hadn’t tried vaping. That translates into 3.6 times higher odds of smoking for people who have tried e-cigarettes, researchers report in JAMA Pediatrics.

One limitation of the study is that it included some results from earlier studies with a high drop-out rate, and it’s not clear whether people who left these studies were different from participants who remained in ways that would make them more or less likely to smoke, the authors note. Researchers also lacked data on the type of e-cigarettes used, and they only looked at U.S. studies.

Even so, by pooling data from several smaller studies, the results offer stronger evidence that vaping can encourage young people to progress to smoking, said William Shadel, a researcher at RAND Corporation in Pittsburgh who wasn’t involved in the current study.

“The results are particularly compelling because the studies took into account other variables that put kids at risk of cigarette smoking, like alcohol use and peer cigarette smoking,” Shadel said by email. “These results should help to strengthen arguments for regulatory action that limits young people’s access to e-cigarettes.”

Enticing flavors of liquid nicotine used in e-cigarettes, like strawberry or chocolate, may make vaping appealing to some young people who might not like the taste of traditional cigarettes, said Dr. Brian Primack, a researcher at the University of Pittsburgh who wasn’t involved in the study. Peer pressure may then encourage them to graduate to smoking.

“Young people report that there is a lot of pressure among e-cigarette only users to smoke a ‘real’ cigarette,” Primack said by email. “It may be somewhat analogous to the fact that teens who use flavored alcohol are often pressured socially to step up their game to harder forms of alcohol.”

There’s one clear way for young people to avoid this.

“The biggest thing that people can do is never start using them in the first place,” Primack said.

CIGARETTE FILTERS MAY INCREASE LUNG CANCER RISK

A study’s authors argue that tiny ventilation holes in virtually all cigarettes sold today are creating a new health risk.

http://ewn.co.za/2017/05/23/cigarette-filters-may-increase-lung-cancer-risk

Cigarette filters, introduced decades ago to reduce the amount of tar smokers inhale, also alter other properties of smoke and smoking in a way that raises the risk of lung cancer, researchers say.

In a review of research on changes in lung cancer rates, and changes in the types of lung cancer that are most common, the study authors argue that tiny ventilation holes in virtually all cigarettes sold today are creating a new health risk.

“The design of cigarette filters that have ventilation can make the cigarettes even more dangerous, because those holes can change how the tobacco burns, allow smokers to inhale more smoke and to think that the smoke is safer because it is smoother,” senior author Dr. Peter D. Shields from The Ohio State University’s Wexner Medical Center in Columbus told Reuters Health by email.

“This applies to all cigarettes, because almost all the cigarettes on the market have the holes, not just the ones that used to be called lights and ultra-lights,” he noted.

Although rates of lung cancer in the population have fallen with declines in smoking overall, rates of lung cancer among smokers have risen significantly, the researchers point out. And the type of lung cancer associated with smoking has also shifted since the 1950s.

Rates of adenocarcinoma of the lung, the lung cancer most associated with smoking, have more than quadrupled in men and increased eight-fold in women along with changes in the design and composition of cigarettes since the 1950s, the researchers write.

Shields and his team review the evidence linking cigarette filter ventilation to these increased rates of lung cancer in a report online 22 May in the Journal of the National Cancer Institute.

Filter ventilation reduces the amount of tar in the cigarette smoke when tested on smoking machines, but the increased ventilation and slower tobacco burn result in more puffs per cigarette and more toxic cancer-causing chemicals being inhaled by smokers, they write.

“The use of the ventilation holes yields lower tar only on a machine,” Shields said. “Machines have nothing to do with actual exposures in humans. The holes let them actually inhale more smoke with more cancer-causing agents.”

Because of the claims of lower tar content, though, smokers develop the false belief that a lower tar cigarette is a healthier cigarette, Shields’ team writes.

Increased filter ventilation also results in smaller particle size, allowing more smoke to reach vulnerable parts of the lung.

Moreover, even though machine-measured tar and nicotine levels have decreased over time, there has been no appreciable change in daily nicotine intake among smokers over the past 25 years, they write.

“The evidence shows that more modern cigarettes are more risky for lung cancer,” Shields said. “There are reasons in addition to the holes that also can contribute to the increasing risk, but one does not preclude the other.”

Cigarette designs could and should be regulated to address all the possible reasons, Shields said.

“The holes have no health benefits; they serve no health purpose,” he explained. “They do not lower tar delivery to people. So, if they have the potential harm, the FDA can act, even if the science is not perfect. The FDA can require cigarette manufacturers to make filters without the holes. This is easy and they are doing it for some brands already.”

Having filters may indeed be safer, Shields clarified. “This study is about the holes on the filters. We are not saying to remove filters, only to change their designs by removing the holes on the filters.”

“The FDA now has the authority to require the elimination of filter ventilation, as ventilation does not serve any public health purpose and instead provides a false promise of reduced risk,” the study team concludes.

“This single action for banning filter ventilation by the FDA is scientifically justified, and within its mandate to improve the public health,” they write.

There is some precedent for the ban Shields and colleagues propose, Jonathan M. Samet and Lilit Aladadyan, both from the Tobacco Center of Regulatory Science at the Keck School of Medicine of USC and the USC Institute for Global Health in Los Angeles, write in an accompanying editorial.

The evidence gathered by Shields’ team seems strong enough to support FDA action, and “given a lack of evidence for countervailing harms, ending filter ventilation could be a ‘no regrets’ action that would benefit public health,” they write.

The Hole Story: Ventilated Filters Make Smoking More Deadly

The ventilation systems built into cigarette filters in the mid-1960s to reduce tar and make smoking ‘smoother’ and ‘safer’ were responsible for the paradoxical rise in rates of lung adenocarcinoma — even as rates of other lung cancer subtypes dropped along with the number of smokers. These conclusions were in the 2014 US Surgeon General’s report on the health consequences of smoking.

http://www.medscape.com/viewarticle/880383

Now, two new weight-of-evidence reviews have pinpointed 25 “causation analysis evidence blocks” that could support an outright ban of filter ventilation, according to lead author, Peter G. Shields, MD, deputy director of the Comprehensive Cancer Center, the Ohio State University Wexner Medical Center, in Columbus, and colleagues.

The review found that between the 1960s and the 1980s, the health risks associated with smoking jumped almost 2-fold in men and increased 10-fold in female smokers. At the same time, the relative risks for adenocarcinomas rocketed from 4.6 to 19.0 in men and from 1.5 to 8.1 in women — even though the risks for other lung cancer subtypes didn’t increase. “Thus, there was a paradoxical increase for lung adenocarcinomas while squamous cell cancers decreased with decreased smoking rates,” the review authors write.

“The analysis strongly suggests that filter ventilation has contributed to the rise in lung adenocarcinomas among smokers,” they say in a report published online May 22 in the Journal of the National Cancer Institute.

“Based on these weight-of-evidence reviews, the FDA [Food and Drug Administration] should embark on a regulatory process of data evaluation and consider regulation(s) for the use of ventilation in filters, up to and including a ban on their use,” the authors conclude.

“The prime point is to rally the troops to get the FDA to focus on this,” Dr Shields told Medscape Medical News. “To me, this is a policy paper. Physicians can’t be silent.”

This is a policy paper. Physicians can’t be silent. Peter D. Shields

Ventilation holes in filters are now found in nearly every brand of cigarettes, and they make smoking even more deadly, Dr Shields elaborated in an interview.

The tiny filter holes slow down tobacco combustion, giving smokers more puffs per cigarette but also allowing more toxic constituents to form, increasing the mutagenicity of the smoke, the review authors explain. To get the requisite nicotine hit from a cigarette with a ventilated filter, a smoker must also inhale more deeply, drawing smoke farther into the lungs and exposing cells vulnerable to adenocarcinoma.

Increasing amounts of tobacco-specific nitrosamines can also be found in new blended tobaccos that provide a “smoother” smoking experience, albeit with more carcinogens, Dr Shields commented. This makes smoking more dangerous than ever before, and patients need to know this, he emphasized.

“As part of your risk counseling, tell patients who smoke that the cigarettes today are more deadly than the cigarettes from 30 or 40 years ago. We need to take away smokers’ perception that any cigarette is safe. It’s like putting your head in a chimney,” Dr Shields said.

Increased Risk for Adenocarcinoma

In an accompanying editorial, Jonathan M. Samet, MD, and Lilit Aladadyan, MS, MPH, say that ending filter ventilation “could be a ‘no regrets’ action that would benefit public health.”

Dr Samet is professor and Flora L. Thornton Chair for the Department of Preventive Medicine at the Keck School of Medicine at the University of Southern California (USC) in Los Angeles, and Aladadyan is center director for the USC Tobacco Center of Regulatory Science.

The editorialists note the review looked at a “large and somewhat poorly circumscribed body of literature” and that the evidentiary threshold required for the FDA to take action is not supported by any record of precedents.

However, they also say that the review’s conclusion about the contribution of filter ventilation to rising rates of lung adenocarcinoma in smokers “is well justified” and supports “the indictment of filter ventilation as increasing risk for adenocarcinoma.”

Filter ventilation was originally designed to lower smoking machine tar yields in so-called light cigarettes marketed primarily to women as a “healthier” alternative to regular cigarettes. “This was done to fool smokers and the public health community into thinking that they actually were safer,” Dr Shields said in a statement.

In 2009, the Family Smoking Prevention and Tobacco Control Act gave the FDA authority to ban tobacco companies from labeling and marketing cigarettes as “low tar” or “light.”

Dr Shields has served as an expert in class action suits against tobacco companies marketing light cigarettes as a healthier alternative. He’s also heard lawyers for Big Tobacco say peer-reviewed evidence was needed. “From our perspective, there is more than enough data to start the process and it’s time for regulation,” he said. “We believe that such an action would drive down the use and toxicity of conventional cigarettes and drive smokers to either quit or use less harmful products. There are some open questions about unintended consequences for enacting a ban, which provides for an important research agenda.”

Future clinical trials could assess smokers switching to filtered cigarettes without ventilation, using a panel of biomarkers to measure exposure to carcinogens and lung toxicants, markers of oxidative damage and inflammation in lung, blood, or/and urine, the review authors suggest. At present, human exposure biomarker studies do not appear to support a causal relationship, they didn’t measure exposure in the lung or “utilize known biomarkers of harm,” they note.

Smokers’ perceptions, and transition to alternate products, should also be assessed, looking at differences by race and ethnicity, sex, age, and vulnerable populations. The effect of filter ventilation on the risk for other diseases, such as chronic obstructive pulmonary disease, could also be studied, they say.

This study was supported by the National Cancer Institute of the National Institutes of Health and the FDA Center for Tobacco Products. Dr Shields and coauthors Neal L. Benowitz, MD, and Theodore M. Brasky, PhD, disclose they have served as consultants and expert witnesses in litigation against tobacco companies. Coauthor K. Michael Cummings, PhD, MPH, declares a relationship with Pfizer Inc. The study authors and editorialists have disclosed no relevant financial relationships.

China: the tipping point in tobacco control

Download (PDF, 205KB)

The Health Effects of Electronic Cigarettes

Download (PDF, 3.4MB)

Ethical considerations of e-cigarette use for tobacco harm reduction

GDE Error: Error retrieving file - if necessary turn off error checking (404:Not Found)