Int. J. Environ. Res. Public Health 2014, 11, 4965-4977; doi:10.3390/ijerph110504965
OPEN ACCESS
International Journal of
Environmental Research and
Public Health
ISSN 1660-4601
www.mdpi.com/journal/ijerph
Article
Effect of Smoking Abstinence and Reduction in Asthmatic
Smokers Switching to Electronic Cigarettes: Evidence for
Harm Reversal
Riccardo Polosa 1,2,3,*, Jaymin Morjaria 4, Pasquale Caponnetto 1,2, Massimo Caruso 1,3,
Simona Strano 1,3, Eliana Battaglia 1,3 and Cristina Russo 1,2,3
1
2
3
4
Department of Clinical and Molecular Biomedicine, University of Catania, Catania 95125, Italy;
E-Mails: p.caponnetto@unict.it (P.C.); mascaru@unict.it (M.C.); simostrano@hotmail.it (S.S.);
eliana.battaglia@hotmail.it (E.B.); kristina_russo@yahoo.com (C.R.)
Centro per la Prevenzione e Cura del Tabagismo (CPCT), Teaching Hospital
―Policlinico-V. Emanuele‖, University of Catania, Catania 95123, Italy
Department of Internal and Emergency Medicine, Teaching Hospital ―Policlinico-V. Emanuele‖,
University of Catania, Catania 95123, Italy
Department of Academic Respiratory Medicine, University of Hull, Castle Hill Hospital, Castle Road,
Cottingham HU16 5JQ, UK; E-Mail: jbmorjaria@gmail.com
* Author to whom correspondence should be addressed; E-Mail: polosa@unict.it;
Tel.: +39-095-3781-583; Fax: +39-095-3781-580.
Received: 3 April 2014; in revised form: 24 April 2014 / Accepted: 30 April 2014 /
Published: 8 May 2014
Abstract: Electronic cigarettes (e-cigs) are marketed as safer alternatives to tobacco cigarettes
and have shown to reduce their consumption. Here we report for the first time the effects of
e-cigs on subjective and objective asthma parameters as well as tolerability in asthmatic
smokers who quit or reduced their tobacco consumption by switching to these products.
We retrospectively reviewed changes in spirometry data, airway hyper-responsiveness (AHR),
asthma exacerbations and subjective asthma control in smoking asthmatics who switched
to regular e-cig use. Measurements were taken prior to switching (baseline) and at two
consecutive visits (Follow-up/1 at 6 (±1) and Follow-up/2 at 12 (±2) months).
Eighteen smoking asthmatics (10 single users, eight dual users) were identified.
Overall there were significant improvements in spirometry data, asthma control and AHR.
These positive outcomes were noted in single and dual users. Reduction in exacerbation
rates was reported, but was not significant. No severe adverse events were noted.
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This small retrospective study indicates that regular use of e-cigs to substitute smoking is
associated with objective and subjective improvements in asthma outcomes.
Considering that e-cig use is reportedly less harmful than conventional smoking and can
lead to reduced cigarette consumption with subsequent improvements in asthma outcomes,
this study shows that e-cigs can be a valid option for asthmatic patients who cannot quit
smoking by other methods.
Keywords: smoking cessation; electronic
methacholine challenge; harm reduction
cigarette;
asthma;
lung
function;
1. Introduction
Smoking prevalence in asthma is comparable to that found in the general population [1] and
cigarette smoking is strongly predictive of the development of new-onset asthma in allergic adults [2].
It is increasingly recognized that the asthmatic smoker may represent a distinct disease phenotype with
increased susceptibility of exacerbations and poor asthma-specific health status [3]. In fact it has been
observed that a smoking history of more than 20 pack-years is associated with more severe disease [4].
Most studies report an accelerated decline in lung function and an increased severity of airflow
obstruction in asthmatic smokers [5]. Moreover, asthma patients who smoke appear to have an
impaired response to the beneficial effects of inhaled corticosteroids (ICS) or oral corticosteroids
compared to asthmatics who do not smoke [6,7].
Of note, worsening asthma symptoms and lung function changes can be reversed with smoking
cessation [8,9]. Unfortunately, there are only modest cessation rates reported in adult asthmatics [10]
as there is a lack of awareness that smoking is a key aetiological component of their
respiratory symptoms [11].
Electronic cigarettes (e-cigs) are battery-operated devices designed to vaporise nicotine without
burning tobacco. These consumer products may be attractive to smokers who consider their tobacco
use a recreational habit that they wish to maintain in a more benign form, rather than a predicament
requiring medical treatment, and also to those smokers who cannot quit with current available
medications due to their low efficacy. Indeed, e-cigs are increasingly being used as an alternative low
risk substitute for conventional cigarettes [12,13].
Although these products have been shown to be effective and safe cigarette substitutes in
randomized controlled trials of ―healthy‖ smokers [14,15], no data is available regarding health effects
of e-cigs use among vulnerable populations, including people with asthma. Moreover, it is unknown if
regular ―vaping‖ (the act of inhaling vapour from e-cigs/personal vaporizers) could result in improved
asthma-related outcomes. Here we report, for the first time, changes in the level of asthma control,
pulmonary function as well as airway hyperresponsiveness (AHR) in a group of asthmatic smokers
who quit or reduced substantially their tobacco consumption by switching to e-cigs.
Int. J. Environ. Res. Public Health 2014, 11
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2. Methods
2.1. Patient Population
Medical records of patients with asthma regularly followed-up in our outpatient clinics were
reviewed. From September 2012 to December 2013, a total of 18 asthmatic patients reporting regular
use of e-cigs on at least two consecutive follow-up visits were identified. All patients had mild to
moderate disease according to the Global Initiative for Asthma (GINA) criteria and treated accordingly
with inhaled corticosteroids (ICS), long-acting (LABA) and on-demand short-acting β2 agonist
(SABA) [16]. This study was approved by the local institutional ERB and informed consent was
obtained from each patient.
2.2. Study Assessments
We obtained patient data from the clinic visit immediately preceding [baseline visit] the first of the
two consecutive follow-up visits (follow-up visits 1 and 2). We also included data from the clinic visit
immediately prior to the baseline visit (pre-baseline visit) to validate disease stability. In brief,
data from four visits were collected and analysed. Pre-baseline visits were carried out at 6–12 months
prior to baseline visits. Follow-up visits 1 and 2 were carried out at 6 (±1) and 12 (±2) months after
baseline visits, respectively. At each clinic visit, patients were reassessed using a standard protocol
consisting of clinical examination, review of smoking history, re-evaluation of treatment adherence
and efficacy. The latter was assessed using: (i) Juniper’s Asthma Control Questionnaire (ACQ)
score [17]; (ii) by annotating the number of exacerbations from the previous follow up visit (an asthma
exacerbation was defined as an increase in respiratory symptoms requiring a short course of oral or
parenteral corticosteroids); (iii) spirometry with parameters of forced expiratory flow in 1 second (FEV1),
forced vital capacity (FVC), expiratory ratio (%FEV1/FVC) and forced expiratory flow at the middle half
of the FVC (FEF25-75%); and (iv) in some subjects bronchial provocation tests assessing Airway
HyperResponsiveness (AHR) with methacholine were also conducted as previously described [18].
2.3. Analyses
Baseline and demographic data were expressed as mean (±standard deviation (SD)) except for
methacholine PC20 values expressed as geometric mean (data range). Post-initiation of e-cig data were
similarly expressed. We also delineated data for single (e-cigs only) and dual users (e-cigs and
conventional cigarettes). Statistical comparisons of parameters assessed were carried out using
student’s T-test and Wilcoxon-signed rank test depending on whether the data was parametric or not,
respectively. Missing measurements were not included in the analyses. A two-tailed p value of less
than 0.05 was considered to indicate statistical significance. All analyses were performed with the
Statistical Package for Social Science (SPSS for Windows version 18.0, IBM Inc., Chicago, IL, USA).
Int. J. Environ. Res. Public Health 2014, 11
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3. Results
3.1. Characteristics of the Patients and of Their E-cig Use
Of the 18 e-cig users identified (11 male, seven females) all were former tobacco smokers of about
20 conventional cigarettes/day. There were 10 single and eight dual users by the time of their most
recent follow-up visit (follow-up visit 2). All dual users smoked ≤5 conventional cigarettes/day.
The pre-baseline and baseline visit patient demographics and characteristics are summarised on Table 1.
All patients initially switched to a cigarette-like model, but the majority went on to adopt a personal
vaporizer. Duration of regular e-cig use ranged from 10 to 14 months, with twelve patients using them
for more than a year. All patients took a stable dose of ICS, LABA as well as on-demand SABA
throughout the observation period. None of the patients included had ever received a significant
modification in anti-asthma therapy from their pre-baseline visit. There were no significant differences
in the measured parameters of lung function, bronchial hyperresponsiveness (BHR) or ACQ scores
between the pre-baseline and baseline visits (except for a small change in FEF25-75%) (Table 1).
Table 1. Patients characteristics at pre-baseline and baseline (before switching to e-cigs).
Parameter
Gender
Age
Asthma Duration
Conventional Cigarettes/Day
Smoking Pack Years
No. Exacerbations
(from the previous follow up visit)
FEV1 (L)
FVC (L)
FEV1/FVC (%)
FEF25-75% (L/sec.)
ACQ
PC20 (mg/mL) *
Notes:
n—number;
Pre-baseline
All Subjects (n = 18)
11M, 7F
37.8 (±12.3)
18.7 (±6.3)
23.2 (±5.1)
20.1 (±9.9)
All Subjects (n = 18)
11M, 7F
38.8 (±12.3)
19.7 (±6.3)
21.9 (±4.5)
21.0 (±10.7)
Baseline
Single Users (n = 10)
7M, 3F
36.1 (±13.5)
18.6 (±6.1)
21.6 (±3.9)
16.5 (±8.4)
Dual Users (n = 8)
4M, 4F
42.3 (±10.6)
21.0 (±6.8)
22.4 (±5.3)
26.6 (±11.2)
1.06 (±1.0)
1.17 (±0.9)
1.20 (±0.8)
1.13 (±1.0)
3.35 (±0.76)
4.33 (±0.85)
77.3 (±5.53)
2.86 (±0.69)
2.07 (±0.36)
1.31 (0.55, 1.75)
3.30 (±0.78)
4.28 (±0.90)
76.8 (±4.52)
2.75 (±0.72)
2.03 (±0.37)
1.24 (0.49, 3.27)
3.42 (±0.84)
4.35 (±0.96)
78.3 (±4.59)
2.95 (±0.53)
2.12 (±0.42)
1.10 (0.49, 2.07)
3.16 (±0.73)
4.19 (±0.88)
75.0 (±3.98)
2.49 (±0.88)
1.93 (±0.29)
1.40 (0.82, 3.27)
M—male;
F—female;
mths—months;
L–litres;
L/sec—litres/second;
%—percentage;
mg/mL—milligram per milliliter; Data expressed as mean (±standard deviation); * Data expressed as geometric mean (range).
3.2. Efficacy of Smoking Reduction in Lung Function, BHR and ACQ Scores
Compared to baseline, at 6 months there were significant improvements in FEF25-75% (Table 2;
Figure 1C) and ACQ scores (Table 2; Figure 2); at 12 months significant improvements were observed
on all asthma outcomes measures, including methacholine PC20 (Table 2; Figures 1–3). Dual users
had similar changes to the overall group at 6 months (Table 2). At 12 months both dual and single
users had considerable improvements compared to baseline in all parameters (except for FVC in
single users) (Table 2).
3.3. Conventional Smoking
There was a marked reduction in conventional cigarette use amongst all e-cig users from a mean
conventional cigarette/day use of 21.9 at baseline decreasing to 1.7 at follow-up visit 2 (p < 0.001)
Int. J. Environ. Res. Public Health 2014, 11
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(Table 2). Similar substantial reduction in conventional cigarette smoking was observed in dual users
as well (22.4 at baseline to 3.9 at follow-up visit 2; p < 0.001) (Table 2). Importantly, 10 asthmatics
gave up conventional cigarette use in favour of the e-cig (single users).
3.4. Exacerbations
Prior to e-cig use in the 18 patients the average number of exacerbations were 1.06 (at pre-baseline)
and 1.17 (at baseline) (Table 2). Over the period of observation none of the subjects in the cohort
reviewed had a hospital or intensive care unit admission. At follow-up visits 1 (0.87 exacerbations)
and 2 (0.78 exacerbations) although there was a reduction in exacerbations compared to baseline
which was not significant (p = 0.296 and 0.153, respectively) the reduction in exacerbations was
marked (>25 and >33 %, respectively) (Table 2).
Table 2. Changes in parameters measured at baseline, 1st- and 2nd follow-up visits.
Parameter
Baseline
All patients (n = 18; 11M, 7F)
FEV1 (L)
3.30 (±0.78)
FVC (L)
4.28 (±0.90)
FEF25-75% (L/sec.) 2.75 (±0.72)
ACQ
2.03 (±0.37)
PC20 (mg/mL) *
1.24 (0.49, 3.27)
Cigarettes/day
21.9 (±4.5)
Exacerbations
1.17 (±0.9)
Single Users (n = 10; 7M, 3F)
FEV1 (L)
3.42 (±0.84)
FVC (L)
4.35 (±0.96)
FEF25-75% (L/sec.) 2.95 (±0.53)
ACQ
2.12 (±0.42)
PC20 (mg/mL) *
1.10 (0.49, 2.07)
Cigarettes/day
21.6 (±3.9)
Exacerbations
1.20 (±0.8)
Dual Users (n = 8; 4M, 4F)
FEV1 (L)
3.16 (±0.73)
FVC (L)
4.19 (±0.88)
FEF25-75% (L/sec.) 2.49 (±0.88)
ACQ
1.93 (±0.29)
PC20 (mg/mL) *
1.40 (0.82, 3.27)
Cigarettes/day
22.4 (±5.3)
Exacerbations
1.13 (±1.0)
1st Follow-up Visit
(6 months ± 1)
2nd Follow-up Visit
(12 months ± 2)
p value to Baseline
p value to Baseline
3.34 (±0.72)
4.34 (±0.86)
3.00 (±0.54)
1.60 (±0.24)
1.20 (0.44, 4.23)
1.9 (±2.9)
0.87 (±0.7)
0.078
0.105
0.006
<0.001
0.594
<0.001
0.296
3.40 (±0.73)
4.43 (±0.78)
3.11 (±0.57)
1.47 (±0.20)
2.56 (0.5, 5.55)
1.7 (±2.1)
0.78 (±0.7)
0.005
0.006
0.001
<0.001
0.003
<0.001
0.153
3.49 (±0.75)
4.52 (±0.86)
3.17 (±0.39)
1.69 (±0.29)
1.14 (0.44, 3.55)
1.13 (±0.6)
0.779
0.161
0.093
0.024
0.463
0.831
3.51 (±0.75)
4.51 (0.81)
3.20 (±0.54)
1.50 (±0.19)
2.06 (0.5, 5.55)
1.10 (±0.7)
0.032
0.059
0.047
<0.001
0.043
0.773
3.17 (±0.71)
4.13 (±0.88)
2.81 (±0.64)
1.50 (±0.15)
1.28 (0.72, 4.23)
5.0 (±2.6)
0.57 (±0.8)
0.062
0.352
0.028
0.004
0.893
<0.001
0.257
3.26 (±0.72)
4.32 (±0.78)
3.01 (±0.62)
1.43 (±0.21)
3.17 (2.39, 4.09)
3.9 (±1.0)
0.38 (±0.5)
0.05
0.05
0.012
0.002
0.028
<0.001
0.078
Notes: n—number; M—male; F—female; L –litres; %—percentage; L/sec.—litres per second; mg/mL—milligram
per milliliter; Data expressed as mean (±standard deviation); *Data expressed as geometric mean (range).
Int. J. Environ. Res. Public Health 2014, 11
Figure 1. (A) Forced expiratory volume (FEV1) at the four timepoints of assessment for
all 18 patients; (B) Forced vital capacity (FVC) at the four timepoints of assessment for all
18 patients; (C) Forced expiratory flow (FEF) 25–75 at the four timepoints of assessment
for all 18 patients.
(A)
(B)
(C)
Notes: Compared to baseline significant p values of **—≤0.01, ***—≤0.001; All data expressed as mean
and error bars are standard error of the mean; Abbreviations: F/up—follow-up; L—litres;
L/sec.—litres per second.
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Figure 2. Asthma control questionnaire (ACQ) score at the four timepoints of assessment
for all 18 patients.
Notes: Compared to baseline significant p values of ***—≤0.001; All data expressed as mean and error bars
are standard error of the mean; Abbreviations: F/up—follow-up.
Figure 3. Methacholine PC20 at the four timepoints of assessment.
Notes: Compared to baseline significant p values of **—≤0.01. All data expressed as mean and error bars are
standard error of the mean; Abbreviations: F/up—follow-up; mg/mL—milligram per millilitre.
3.5. Safety and Tolerability
No severe adverse reactions or acute exacerbation of asthma symptoms (i.e., cough, wheeze) were
reported during period of observation with e-cig use. Overall, e-cig use appears to be well tolerated in
these asthmatic patients with dry mouth and throat irritation being occasionally reported.
4. Discussion
Here, we show for the first time improvements in asthma control, AHR and pulmonary function in
asthmatic smokers who quit or dramatically reduced their tobacco consumption by switching to e-cigs.
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These preliminary findings are of great consequence considering that many asthmatic patients
continue to smoke and seem uninterested in quitting [3,8], a paradox that may be explained by the
highly addictive nature of tobacco smoking and the remitting clinical nature of asthma, particularly in
its mild-to-moderate forms. The success with e-cig observed in these patients may be explained by the
great compensatory effect of e-cigs at both physical and behavioural level [12]; in particular these
products are known to provide a coping mechanism for conditioned smoking cues by replacing some
of the rituals associated with smoking gestures (e.g., hand-to-mouth action of smoking). In agreement
with this, we have demonstrated that nicotine free plastic inhalators can only improve quit rates in
those smokers for whom it was shown that cigarette handling and manipulation played an important
role in their smoking ritual [18].
This study has demonstrated that lung function of smokers with asthma may improve when
stopping smoking for a sufficient period of time. The level of improvement was small and likely to be
clinically irrelevant, but statistically significant. In asthma, there have been two previous studies
looking at the effect of stopping smoking on lung function [8,9], and our retrospective findings are in
agreement with the positive results of these prospective studies. Taken together, the evidence suggests
that the harmful effects of smoking on the asthmatic airways can be reversed. The improvement in
lung function could be due to a reduction in the pro-inflammatory effects of cigarette smoke on the
airways [3,19]. It is also possible that stopping smoking leads to a reduction in corticosteroid
insensitivity, as smoking asthmatic patients appear to be less sensitive to the beneficial effects of inhaled
corticosteroids (ICSs) on lung function compared with non-smoking asthmatic patients [6,20,21] and
stopping smoking by switching to e-cigs may allay this unresponsiveness to ICSs.
It was interesting to note an early improvement in FEF25–75% values in the asthmatic smokers
who successfully quit smoking with e-cigs use, whereas no significant change was detected in FEV1 or
FVC at the first follow-up visits immediately after e-cig switch. Larger clinical trials are required to
shed more light on the significance of these findings in relation to previous smoking history and to
current vaping behaviour.
There were significant improvements in BHR, in the asthmatic smokers who had been abstinent or
reduced their tobacco consumption long enough. The level and time-course of the observed changes in
PC20 methacholine are not unexpected and consistent with the results of prospective studies in allergic
subjects for whom an objective proof of cessation was documented [22]. The observed improvement in
BHR may have important clinical implications. For instance, it is well known that, independent of
smoking status, individuals with documented AHR are known to be at risk for asthma symptoms and
attenuated pulmonary function levels [23,24]. Thus, improving AHR may confer some clinical benefit
as documented in the asthmatic patients of this study. The explanation for the improvement in AHR is
unknown, but probably relates to the gradual and progressive reduction in smoke-induced
inflammatory changes on the airways of those who quit and/or to the reversal of corticosteroid
insensitivity [3,19].
We have also observed early and stable improvements in asthma control (i.e., ACQ scores) that are
clinically relevant. This is not surprising considering the established relationship between smoking and
poor asthma control reported in population-based surveys [25,26] and controlled studies [4,27].
In spite of significant improvement in lung function, AHR and asthma control, no significant
change in disease exacerbations was observed. This discrepancy can be explained by the low baseline
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values for exacerbations in our mild-to-moderate asthmatic patient cohort (hence it is possible that
scope for further improvement was limited), the small sample size, and the modality of documenting
exacerbations which was liable to recall bias.
Of interest, consistent improvements in subjective and objective asthma outcomes were also
observed amongst dual users (i.e., heavy reducers) with no real difference in dual compared to single
users by the end of the observation period. Surprisingly, early improvement in FEF25–75% values
were shown only in dual users (unlike in single users). This could be due to substantial differences in
the level of exposure to tobacco smoke between single and dual users (mean pack/years 16.5 in single
vs. 26.6 in dual users) and, consequently, to the much higher FEF25–75% values at baseline in single
compared to dual users (thus limiting room for further improvement in single users). An alternative
explanation is that the observed early improvement in FEF25–75% values could be the result of a
chance finding given the small sample size.
It is impossible to know for sure whether e-cig use drove the observed positive changes in asthma
outcomes, but clearly was not reported to be harmful in mild-to-moderate asthmatics in this study.
None of the patients reported severe adverse reactions or acute exacerbation of asthma symptoms
during e-cig use. Their use appears to be well tolerated with occasional dry mouth and throat irritation
being reported. The current evidence indicates that e-cigs are by far a less harmful alternative to
tobacco smoking and have a potential significant health benefit in smokers who switch to
these products [28].
By substantially reducing number of cigarettes smoked per day and exposure to their hazardous
toxicants, e-cigs may not only improve asthma symptoms and pulmonary function but may also confer
an overall health advantage in smokers with asthma [13]. 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).
There are some limitations in our study. Firstly, this is a small retrospective study, hence the results
observed may be due to bias and not due to a true effect; and consequently be interpreted with caution.
However, despite being a small study we were able to detect positive significant changes for several
asthma outcomes. Standard issues associated with retrospective studies (including variance in the
quality of information recorded by medical professionals and difficulty in establishing a causal
relationship) need consideration. Nonetheless, a clear advantage of conducting such studies is that they
permit the generation of hypotheses that then would be tested prospectively under controlled
conditions. Secondly, patients in this study may represent a self-selected sample, which is not
representative of all asthmatic smokers who switch to e-cigs. Thirdly, assessment of symptoms in our
patients was not rigorous and liable to recall bias. Although it is unlikely that the experience of
troublesome symptoms upon switching may have been easily forgotten, the good tolerability reported
by these patients should be also considered with prudence. Lastly, smoking abstinence was
self-reported. However, self-reported number of cigarettes smoked per day in studies of this type is not
subjected to the kind of biases observed in clinical trials where there is the tendency to claim
abstinence [29]. Moreover, similar beneficial effects were also reported in dual users
(i.e., smoking reducers) and therefore objective measures of abstinence are unlikely to be
of great importance.
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5. Conclusions
The e-cig may help smokers with asthma to reduce their cigarette consumption or remain abstinent
and hence reduce the burden of smoking-related asthma symptoms. The positive findings observed
with e-cigs allows us to advance the hypothesis that these products may be valuable for smoking
cessation and/or tobacco harm reduction also in asthma patients who smoke. Large randomized
controlled trials are now needed to confirm and expand these preliminary observations.
Acknowledgements
Riccardo Polosa is full Professor of Internal Medicine with tenure and he is supported by the
University of Catania, Catania, Italy. Riccardo Polosa’s research on smoking, electronic cigarettes and
asthma is currently supported by University of Catania and LIAF (Lega Italiana AntiFumo, Catania,
Italy). The authors wish to thank SET Srl (Turin, Italy) for the collaboration.
Author Contributions
Riccardo Polosa was involved in the concept development, data interpretation and drafting the
manuscript. Jaymin Morjaria carried out the data analyses, was involved in their interpretation and
revised the manuscript. Pasquale Caponnetto was involved in data interpretation and revised the
manuscript. Massimo Caruso was involved in data interpretation and revised the manuscript.
Simona Strano was involved in the review of medical records and data collection. Eliana Battaglia was
involved in the review of medical records and data collection. Cristina Russo was involved in data
interpretation and revised the manuscript. All authors have read and approved the final manuscript.
Conflicts of Interest
Riccardo Polosa has received grant support from anti-asthma drug manufacturers including CV
Therapeutics, NeuroSearch A/S, Sandoz, Merck Sharp & Dohme, and Boehringer-Ingelheim;
has served as a speaker for CV Therapeutics, Novartis, Merck Sharp & Dohme, and Roche;
has served as a consultant for CV Therapeutics, Duska Therapeutics, Neuro-Search A/S,
Boehringer-Ingelheim, and Forest Laboratories; and has received payment for developing educational
presentations from Merck Sharp & Dohme, Novartis, and Almirall. Riccardo Polosa has also received
lecture fees and research funding from GlaxoSmithKline and Pfizer, manufacturers of stop smoking
medications; he has also served as a consultant for Pfizer and Arbi Group Srl, an italian e-cigs
distributor. Riccardo Polosa’s research on e-cigs, smoking and asthma is supported by Lega Italiana
AntiFumo (LIAF). Jaymin B. Morjaria has received honoraria for speaking and financial support to
attend meetings/advisory boards from anti-asthma drug manufacturers including Wyeth, Chiesi, Pfizer,
Merck Sharp & Dohme, Boehringer-Ingelheim, Teva, GlaxoSmithKline/Allen & Hanburys, Napp,
Almirall, and Novartis. Pasquale Caponnetto, Massimo Caruso, Simona Strano, Eliana Battaglia,
and Cristina Russo declare no conflicts of interest.
Int. J. Environ. Res. Public Health 2014, 11
4975
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