A new study published in the journal JAMA Pediatrics reports on the use of varenicline, a drug that helps smokers quit. The study is unique in that it targeted teenagers who wanted to quit. While confirming the low overall efficacy of the drug, it shows that it may perhaps help teenage smokers to quit faster and to stay smoke-free longer.
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Almost all smokers today began before they turned 21. Moreover, almost all of them will continue to do so as adults, and their lifespan will be shortened by 10 years, on average. While 2 out of 3 teenagers who smoke would like to quit, this actually happens, successfully, in only 4% to 6% of all of them. This involves understanding the different motivations in this age group, the immature mental apparatus, and the difficulty in understanding the long-term consequences.
Many preventable deaths are caused by lack of proper intervention by public health authorities. Among these, smoking-related deaths top the list both globally and in America. And even worse, millions of teenagers (about 5 million) use tobacco, according to 2018 estimates by the US Department of Health.
Most anti-smoking campaigns focus on adults. Adults often decide to quit for health reasons, and often because these have already begun to manifest. Most quitters are in their 30s or further on.
However, teenagers often face much more peer pressure to smoke than adults do. They are more prone to high-risk behaviour, to experiment with addictive drugs and substances, and to ignore possible long-term consequences of their present actions which are unreal at this period of their lives.
Varenicline tartrate is a drug which acts as a partial agonist at the α4β2 nicotinicacetylcholine receptor. It is available under the brand name Chantix and is a commonly used medication for smokers who want to quit. Its efficacy has been proved in adults to be up to 6 times more effective than a placebo, and about twice as effective as the nicotine patch or bupropion.
The current study focused on its use in adolescents who want to quit. To compare the efficiency of the drug in adults versus children, the researchers used the exact same protocol that had been used previously in adults.
The drug was given in combination with other treatments for 12 weeks to 157 adolescents who had smoked daily for at least 6 months and had tried unsuccessfully to quit at least once. The participants were first classified by age into two groups, 14-17 years and 18-21 years, and by baseline smoking level (12 or more cigarettes a day compared to less than 12). Then individuals in both groups were randomly assigned either varenicline or placebo. Weekly visits were scheduled for treatment, and follow-up visits at week 18 and 26.
When the results were evaluated after 12 weeks, there was no difference between the placebo and the treatment group in terms of the number of people who quit for at least 7 days at a stretch after treatment, at about 9% in each. 35% of the participants reported they had stopped smoking for at least 7 successive days while on treatment. Of these, 30% and 40% were in the varenicline and placebo groups, respectively.
However, with age and baseline smoking adjustments, those who received varenicline were almost twice as likely to report abstinence during the treatment period. They had a median 39 days to the first reported 7 days of abstinence, vs 59 days in those on placebo.
The varenicline participants were also less likely to relapse after treatment was completed. Post-treatment abstinence, in other words, that is, the chance that the individual would stay smoking-free for at least 7 days after the end of treatment, was 80% greater in the varenicline group.
Researcher Kevin Gray says, “The group differences at the end of treatment, considered in isolation, may not always be the most important marker of efficacy. The nuanced piece of it is quitting smoking earlier on in treatment, which in our study occurred in the varenicline group compared to the placebo group, is a better indicator of a participant's long-term success.”
Secondly, the researchers found that this medication worked less effectively in teenagers compared to adults, and its standalone results weren’t as great as in combination with other therapies, in this age group. The overall rate of successful quitting was lower in this trial, compared with earlier adult trials. This, they say, is an expected finding.
One strong determinant of quitting success, says Gray, is the motivation of the individual. The desire to stop smoking is not a constant fire but rather a leaping, uncertain flame – more like a dimmer than an off-on switch. Sometimes it’s more, sometimes less. And this behaviour is especially unpredictable at adolescence. It is also dependent on life situations, and as a result, in adolescence, varencline alone is less effective than when used along with behavioural therapy and other treatment measures.
As part of a larger team that works on the issues surrounding the treatment of substance abuse in adolescents and their families, Gray expects his team to start work next on how unconventional treatments work in this group. For instance, adolescents are limited in their flexibility as to clinic appointments, because they must attend school as well. Transportation is another bottleneck. So, they want to investigate the success of using mobile devices to offer quitting treatment more effectively.
Says Gray, “Too often, we make the assumption that adolescents are just little adults. And so, we treat them the same way as we do our adult patients. But it's much more complicated than that. We want to match our treatments to the needs of adolescents. And part of that is truly understanding where adolescents are with smoking and designing treatments around that.”
Efficacy and safety of varenicline for adolescent smoking cessationa randomized clinical trial. Kevin M. Gray, Nathaniel L. Baker, Erin A. McClure, Rachel L. Tomko, Lindsay M. Squeglia, Michael E. Saladin, and Matthew J. Carpenter. JAMA Pediatrics 2019;173(12):1146-1153. doi:10.1001/jamapediatrics.2019.3553, https://jamanetwork.com/journals/jamapediatrics/fullarticle/2753036