New Study Investigates the Benefits of Switching to Vaping for Asthmatic Smokers
By Lindsay Fox Posted June 13, 2014
With the global push to regulate the hell out of e-cigarettes as if they’re some huge threat to public health, it’s important to remember just how much damage they could help avert, particularly for the most at-risk groups of smokers. For asthma-sufferers, smoking is associated with more exacerbations of their condition, their lung function declining more quickly and the corticosteroids used for treatment creating less of a positive effect. The widespread use of vaping as a smoking substitute has understandable potential to reduce the problems among asthma-sufferers, but there was previously no research to support this assertion.
A new study from Professor Riccardo Polosa and colleagues investigates the improvements seen in asthma-suffering smokers who either notably reduce or entirely quit smoking due to vaping. Although it only uses a small sample, it offers initial evidence that both objectively and subjectively measured asthma outcomes improve after switching, and suggests that vaping could be a viable alternative for asthmatic smokers unable to quit nicotine entirely.
- Researchers looked at data from 18 asthmatic smokers who were vaping at two consecutive follow-up clinic visits between late 2012 and 2013. Baseline and pre-baseline data were also used to show that any changes weren’t part of a trend from before the individual started vaping.
- Asthma control questionnaires, spirometry tests and airway hyper-responsiveness tests were conducted, and any exacerbations in condition were noted.
- After a year, statistically significant improvements were seen in spirometry data, asthma control and airway hyper-responsiveness tests in both the full-switchers and the dual users.
- 10 of the 18 participants quit smoking entirely by vaping, and the dual users reduced their average daily cigarette consumption from 22.4 to 3.9 after a year. However, this research wasn’t designed to determine the effectiveness of e-cigs for smoking cessation in asthmatics.
- No participants needed to be admitted to intensive care or hospital during the study period, and the number of exacerbations decreased overall, but this difference was not significant. However, throat irritation and dry mouth were the only reported side effects.
- The benefits observed in participants’ conditions are expected to be related to quitting smoking rather than vaping itself, but the research does indicate that e-cigs are well-tolerated in asthmatics.
- The small sample size and retrospective nature of the reporting in the study are important limitations, but the findings appear in agreement with existing knowledge about the benefits of quitting or substantially reducing smoking for asthmatics.
What They Did – Looking at Vaping and Dual-Using Asthmatics
The researchers looked through medical records of patients with asthma who visited outpatient clinics regularly, identifying 18 asthmatic smokers (11 male and 7 female), who reported being current vapers on at least two consecutive follow-up visits, to participate in the study. The patients attended between September 2012 and December 2013, all had mild to moderate cases of asthma and also received treatment as usual. The researchers identified baseline visits for the patients (at which point they were smokers), and also obtained records of the visit prior to the baseline to establish that the patients’ conditions were stable (i.e. not already improving prior to the baseline). The follow-ups occurred at roughly six months (plus or minus one month) and one year (plus or minus two months) after the baseline visit, and patients were re-assessed at each to determine the state of their condition. The researchers used an asthma questionnaire, noted any exacerbations in their conditions (a short-term increase in symptoms requiring additional treatment), conducted spirometry tests on lung function and for some patients tests assessing airway hyper-responsiveness were also conducted.
From the 18 patients, 10 only used e-cigs (were “single” users) and 8 were also smoking (dual users) at the end of the study period, and all of them previously smoked around 20 cigarettes per day. They started vaping with cig-a-like models, but soon switched to more advanced PVs, and had been vaping for 10 to 14 months by the end of the study. The baseline and pre-baseline measurements of lung function, hyper-responsiveness and questionnaire scores showed no significant difference, indicating that their conditions weren’t improving (or worsening) prior to baseline.
What They Found – Single or Dual-Use Vaping Leads to Positive Outcomes in Asthmatics
At the six-month follow up, the questionnaire scores and one of the lung function parameters had improved in the participants, with the dual and single users showing similar improvements. After a year, all of the asthma outcomes measured in the research had shown statistically significant improvements for both dual and single users, with the exception of the measurement of the total amount of air the patient can exhale in the single users.
During the observation period, none of the participants needed to be admitted to intensive care or a hospital, and there was a general reduction in the number of exacerbations compared to the baseline measurement. This wasn’t a statistically significant change, however, meaning that this finding isn’t convincing enough to rule out the potential effect of chance variation. However, throughout the study period, there were no adverse reactions or acute increases in symptoms (like coughing and wheezing) associated with vaping, aside from occasional reports of throat irritation and dry mouth.
Although the research can’t offer evidence for the effectiveness of e-cigarettes for quitting smoking, the rate of quitting and substantial reduction in cigarette consumption is still worth noting. 10 of the participants quit smoking entirely through vaping, and for the whole sample, the average number of cigarettes per day decreased from 21.9 at the baseline to 1.7 at the one-year follow-up. For the dual users only, they started out at 22.4 cigs per day and reduced to just 3.9 per day after a year.
What Does it Mean?
Generally speaking, the researchers assume that the improvements observed are related to quitting (or drastically reducing) smoking rather than an effect of vaping in itself. This is therefore a fairly expected finding; for example, the lung function improvements associated with quitting smoking have previously been observed in other research, and this is expected to be due to cigarette smoke’s inflammatory effect on the airways (or its impact on the effectiveness of asthma medications). These are also suggested as explanations for the improvements observed in airway hyper-responsiveness.
The improvements seen in hyper-responsiveness could offer some clinical benefit and the improvement in asthma control questionnaire scores is considered clinically relevant by the authors, but the general lung function results were not. This is because the improvements observed in lung function were statistically significant, but from a practical perspective were small enough to be effectively irrelevant. It shows that there is an improvement, but is unlikely to translate to notable clinical improvements.
Considering that all other outcome measures showed improvement after switching to vaping, the researchers noted the lack of a change in the number of exacerbations of the condition. They assume that this is because of the relative rarity of exacerbation in the mild to moderate sufferers studied, meaning that there is limited “room” for improvement in this area among these patients, and would be particularly difficult to detect with a small sample size such as this.
One persistent concern about e-cigarettes is that “dual users” (who also smoke) may not be benefiting as much as they’d imagine by reducing the number of cigarettes they smoke, but this study found that the improvements observed in asthmatic dual users were basically the same as those observed in full-switchers. In fact, one outcome measure improved more quickly in dual users, which the researchers expect is due to the greater level of smoking reduction in the dual users (who’d smoked more on average than those who successfully quit). This essentially allowed them more “room” for improvement of the measurements after reducing smoking. Of course, they did reduce their consumption quite dramatically (from over 20 to 5 cigs per day after six months), so this should be taken into account when considering how this may apply to other dual users.
An important element of this research is its implications for asthmatic smokers, who – despite their condition – generally appear uninterested in quitting. Although the sample was effectively self-selected (those who vaping appealed to started vaping, rather than e-cigs being assigned to random asthmatics), the research does show that e-cigarettes appear to be effective for asthmatics trying to quit. The researchers speculate that the combination of behavioral and physical elements of e-cig use (providing nicotine with the characteristic hand-to-mouth action) is the likely cause of this effect.
The authors point out that although it’s not certain whether e-cig use led to the positive outcomes for the patients included in this study, it can be said that there was no report or indication of harm from switching to vaping, suggesting that vaping is well-tolerated in asthmatic smokers. The researchers conclude that:
“Therefore, e-cig use in asthmatic smokers unable or unwilling to quit should be exploited as a safer alternative approach to harm-reversal (i.e., specific reversal of asthma-related outcomes) and, in general, to harm-reduction (i.e., overall reduction of smoke-related diseases).”
The research is only preliminary, however, and more rigorously-controlled studies will be needed to confirm the observed benefits. The main limitations of the research are its small sample size and the retrospective nature of much of the reporting. In essence, it’s difficult to establish a causal relationship from research like this, and the information recorded by different medical professionals (since medical records were used) may differ in quality. There is also some chance of recall bias in the reporting of symptoms (forgetting a minor, transient symptom, for example) and the fact that abstinence from smoking was self-reported. Despite this, it offers an initial positive finding that will undoubtedly be strengthened by future findings due to the known benefits of quitting smoking and the comparative safety of vaping.
As politicians, journalists and regulators attempt to paint e-cigarettes as a cause for concern or a threat to public health; studies like this continue to reveal more about the probable huge benefits of making the switch. Future studies looking at these same outcomes with more rigorous controls will offer more compelling evidence, but as an initial finding that seems to fit with our existing knowledge on the subject, even the results from this small study are good reason to assume that asthmatic smokers switching to vaping will see an improvement in their condition over time.