Chronic Obstructive Pulmonary Disease (COPD) is a group of inflammatory lung diseases that causes diminished lung function and results in difficulty breathing. There is no cure; the progression of the disease can only be slowed and the symptoms improved. In developed countries, the primary cause of COPD is smoking and patients are therefore advised to quit in order to slow the disease process. COPD significantly decreases life span and quality of life, which taken together, account for 30.2 million years lost due to
early death or disability worldwide.

Although patients are often aware that the cessation of smoking is
a key step to improving their quality of life, many find it difficult to abstain, which ultimately exacerbates
their condition. And, this is despite the many established smoking cessation
treatments and therapies, which simply do not result in long-term abstinence
for many COPD patients. In light of this, it has been proposed that
e-cigarettes may be an appropriate alternative to conventional quit methods for
COPD patients, as they can potentially reduce the risk of relapse while
providing a safer form of consumption.

Accordingly, Riccardo Polosa et al. undertook a three-year study of
48 COPD patients who smoke combustible cigarettes and/or e-cigarettes to analyze
differences in lung function, quality of life and COPD exacerbations in two
ways: 1) they tracked changes from the baseline period within groups
(e-cigarette users or combustible cigarette smokers) and compared the
trajectory of symptom progression across time (from baseline to 36 months for
those who used e-cigarettes and those who did not); and 2) they evaluated differences
between groups of patients who exclusively use combustible cigarettes and those
who use e-cigarettes (exclusively or as dual users) over the course of three
years. The study’s findings reinforced the previous NHIS survey analysis,
which found that COPD patients reported improved respiratory symptoms after
switching from combustible cigarettes to e-cigarettes. It also extends these
findings to include specific measures of disease progression and lung function.

Overall, patients who switched completely to e-cigarettes had
favorable outcomes compared to those who continued to smoke and experienced no
change in either measure of disease severity. Improvements were demonstrated in
three specific measures of respiratory symptoms and disease progression: 1) an
improvement in the assessment tool that measures the impact of COPD on patients;
2) a decrease in the number of COPD exacerbations, such as asthma attacks; and
3) increased distance in the six-minute walk test that measures exercise
capacity. These improvements were both sustained and significant within the electronic
cigarette (EC) group over time (improvements from baseline to 36 months) and
also significant between the EC groups (exclusive and dual users) and the
smoking group (those who used ECs showed marked improvement compared to the
control group).

Perhaps the most interesting finding is that, while officially
deemed dual users, those who used e-cigarettes dramatically decreased their use
of combustible cigarettes—from 21.9 cigarettes per day when first evaluated to
1.5 cigarettes per day at final evaluation 36 months later. What’s more, this
decrease was only observed among the
e-cigarette users, as the average cigarette consumption per day among
combustible cigarette smokers remained stable throughout the same observation

As an observational, COPD patients dictated their own product use throughout
the study period. This means that the investigators did not dictate what group
people were assigned to but rather that participants self-selected based on the
group they felt most accurately represented their usage. The authors compared a
control group—COPD patients who exclusively use combustible cigarettes—to a
group of COPD patients who use e-cigarettes. In this study population, the
relapse rate for the e-cigarette user group (patients who completely
discontinued use of e-cigarettes and returned to using combustible cigarettes)
was very low. In fact, over the 36-month study period, only two patients (8.3 percent)
from the e-cigarette use group returned to exclusive cigarette smoking. Interestingly,
other studies have shown that about 50-percent of smokers with COPD who
achieved abstinence from combustible cigarettes using traditional quit methods,
like Chantix, resumed smoking within one year.

Overall, Polosa et al.’s findings
are promising both in terms of the potential for e-cigarettes to assist those
with COPD and for what they suggest more broadly about the efficacy of
e-cigarettes compared to other smoking cessation methods. One potential
drawback to the study that should be noted, however, is the small sample size
in terms of patients observed. While the differences between the two groups of
patients are statistically significant with a high degree of certainty, studies
with larger sample sizes are considered more reliable. However, it is also true
that as sample size increases, studies can detect smaller differences between
exposure groups and this suggests that a larger sample would also detect a
significant association. For these reasons, further investigation to examine
the potential for e-cigarettes to act as a substitute for combustible
cigarettes on a larger scale is warranted.

And finally, it is important to note that the demonstrated health
improvements were significant, but the study only compared populations that did
not quit or used e-cigarettes. Using a harm reduction framework, e-cigarettes
can be valuable to populations that find quitting difficult and can act as a
substitute for combustible cigarettes for those who do not plan to quit or those
who relapse. However, to encourage the promotion of e-cigarettes as an
appropriate substitute among the medical community, a side-by-side comparison
of the trajectory of symptoms and disease progression associated with
e-cigarettes and currently approved and promoted treatments (such as nicotine
replacement or varenicline) is necessary.

Notwithstanding these avenues for future research, Polosa et al.’s
findings could have a significant impact on the 39 percent of COPD patients who
continue to smoke after their diagnosis. And, in any event, the study adds to
the growing body of literature that indicates switching from combustible
cigarettes to e-cigarettes can improve health outcomes, especially among
patients already suffering from smoking-related illnesses.

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