Constantine I. Vardavas

Short-term Pulmonary Effects of Using an Electronic Cigarette Impact on Respiratory Flow Resistance, Impedance, and Exhaled Nitric Oxide

BACKGROUND Debate exists over the scientific evidence for claims that electronic cigarettes (e-cigarettes) have no health-related ramifications. This study aimed to assess whether using an e-cigarette for 5 min has an impact on the pulmonary function tests and fraction of exhaled nitric oxide (Feno) of healthy adult smokers. METHODS Thirty healthy smokers (aged 19-56 years, 14 men) participated in this laboratory-based experimental vs control group study. Ab lib use of an e-cigarette for 5 min with the cartridge included (experimental group, n = 30) or removed from the device (control group, n = 10) was assessed. RESULTS Using an e-cigarette for 5 min led to an immediate decrease in Feno within the experimental group by 2.14 ppb (P = .005) but not in the control group (P = .859). Total respiratory impedance at 5 Hz in the experimental group was found to also increase by 0.033 kPa/(L/s) (P < .001), and flow respiratory resistance at 5 Hz, 10 Hz, and 20 Hz also statistically increased. Regression analyses controlling for baseline measurements indicated a statistically significant decrease in Feno and an increase in impedance by 0.04 kPa/(L/s) (P = .003), respiratory resistance at 5 Hz by 0.04 kPa/(L/s) (P = .003), at 10 Hz by 0.034 kPa/(L/s) (P = .008), at 20 Hz by 0.043 kPa/(L/s) (P = .007), and overall peripheral airway resistance (β, 0.042 kPa/[L/s]; P = .024), after using an e-cigarette. CONCLUSIONS e-Cigarettes assessed in the context of this study were found to have immediate adverse physiologic effects after short-term use that are similar to some of the effects seen with tobacco smoking; however, the long-term health effects of e-cigarette use are unknown but potentially adverse and worthy of further investigation.

Original ResearchTobacco Cessation and PreventionShort-term Pulmonary Effects of Using an Electronic Cigarette: Impact on Respiratory Flow Resistance, Impedance, and Exhaled Nitric Oxide

BACKGROUND Debate exists over the scientific evidence for claims that electronic cigarettes (e-cigarettes) have no health-related ramifications. This study aimed to assess whether using an e-cigarette for 5 min has an impact on the pulmonary function tests and fraction of exhaled nitric oxide (Feno) of healthy adult smokers. METHODS Thirty healthy smokers (aged 19-56 years, 14 men) participated in this laboratory-based experimental vs control group study. Ab lib use of an e-cigarette for 5 min with the cartridge included (experimental group, n = 30) or removed from the device (control group, n = 10) was assessed. RESULTS Using an e-cigarette for 5 min led to an immediate decrease in Feno within the experimental group by 2.14 ppb (P = .005) but not in the control group (P = .859). Total respiratory impedance at 5 Hz in the experimental group was found to also increase by 0.033 kPa/(L/s) (P < .001), and flow respiratory resistance at 5 Hz, 10 Hz, and 20 Hz also statistically increased. Regression analyses controlling for baseline measurements indicated a statistically significant decrease in Feno and an increase in impedance by 0.04 kPa/(L/s) (P = .003), respiratory resistance at 5 Hz by 0.04 kPa/(L/s) (P = .003), at 10 Hz by 0.034 kPa/(L/s) (P = .008), at 20 Hz by 0.043 kPa/(L/s) (P = .007), and overall peripheral airway resistance (β, 0.042 kPa/[L/s]; P = .024), after using an e-cigarette. CONCLUSIONS e-Cigarettes assessed in the context of this study were found to have immediate adverse physiologic effects after short-term use that are similar to some of the effects seen with tobacco smoking; however, the long-term health effects of e-cigarette use are unknown but potentially adverse and worthy of further investigation.

Smoking and smoking cessation during early pregnancy and its effect on adverse pregnancy outcomes and fetal growth

Maternal smoking during pregnancy is a significant threat to the fetus. We examined the association between active maternal smoking and smoking cessation during early pregnancy with newborn somatometrics and adverse pregnancy outcomes including preterm delivery, low birth weight, and fetal growth restriction. One thousand four hundred mother–child pairs with extensive questionnaire data were followed up until delivery, within the context of a population-based mother–child cohort study (Rhea study), in Crete, Greece, 2007–2008. Comparing smokers to nonsmokers, the adjusted odds ratio (OR) was 2.8 [95% confidence interval (CI), 1.7, 4.6] for low birth weight and 2.6 (95%CI: 1.6, 4.2) for fetal growth restriction. This corresponded to a 119-g reduction in birth weight, a 0.53-cm reduction in length, and a 0.35-cm reduction in head circumference. Smoking cessation early during pregnancy modified significantly these pregnancy outcomes indicating the necessity for primary smoking prevention.

Adolescents perceived effectiveness of the proposed European graphic tobacco warning labels.

BACKGROUND Graphical tobacco product labelling is a prominent source of health information and has an important position among tobacco control initiatives. However, little is known about its effectiveness among adolescents. With this above in mind, we aimed to research into how adolescents perceive the proposed EU graphic tobacco product warning labels as an effective means of preventing smoking initiation in comparison to the current EU text-only warning labels. METHODS Five hundred seventy four adolescents (13-18, 54% male) from Greece were privately interviewed, with the use of a digital questionnaire and randomly shown seven existing EU text-only and proposed EU graphic warning labels. Non-smoking respondents were asked to compare and rate the warnings effectiveness in regard to preventing them from smoking on a 1-5 Likert type scale. RESULTS Irrespective of the warning category shown, on all occasions, non-smoking adolescents rated the suggested EU graphic labels as more effective in preventing them from smoking in comparison to the existing EU text-only warnings. Controlling for gender, age, current smoking status and number of cigarettes smoked per month, younger adolescents were found to opt for graphic warnings more often, and also perceive graphic warning labels as a more effective means of preventing them from smoking, in comparison to their elder peers (P < 0.001). CONCLUSIONS The proposed EU graphic warning labels may play an important role in preventing of smoking initiation during the crucial years of early adolescence when smoking experimentation and early addiction usually take place.

Biological evidence for the acute health effects of secondhand smoke exposure

A vast number of studies on the unfavorable effects of secondhand smoke (SHS) exist within the international literature, the majority of which evaluate longitudinal epidemiological data. Although limited, the experimental studies that assess the acute and short-term effects of exposure to SHS are also increasing in number. They include cellular, animal, and human studies that indicate a number of pathophysiological mechanisms through which the deleterious effects of SHS may arise. This current review evaluates the existing biological evidence regarding the acute health effects of SHS exposure. Analyses on the inhaled toxicants and the carcinogenicity of SHS are included as well as in-depth discussions on the evidence for acute SHS-induced respiratory, cardiovascular, metabolic, endocrine and immune effects, and SHS-induced influences on oxygen delivery and exercise. The influence of the length of exposure and the duration of the observed effects is also described. Moreover, recent findings regarding the underlying pathophysiological mechanisms related to SHS are depicted so as to generate models that describe the SHS-induced effects on different systems within the human body. Based on the presented biological evidence, it is concluded that brief, acute, transient exposures to SHS may cause significant adverse effects on several systems of the human body and represent a significant and acute health hazard. Future research directions in this area include research on the concentrations of tobacco smoke constituents in the alveolar milieu following SHS exposure, individual susceptibility to SHS, as well as the effects of SHS on neurobehavioral activity, brain cell development, synaptic development, and function.

Current evidence on the associations of breastfeeding, infant formula, and cow's milk introduction with type 1 diabetes mellitus: a systematic review.

Current evidence provides contradictory results in regards to the associations of breastfeeding or early introduction of cows milk and formula with the development of type 1 diabetes (T1D). The aim of this systematic review was to evaluate the type of feeding, duration of breastfeeding, time of introduction of formula or cows milk, and the potential impact on developing T1D. The literature search was conducted based on the standards outlined in the MOOSE Guidelines for Meta-Analyses and Systematic Reviews of Observational Studies and yielded a total of 161 studies, 28 of which were included in this review. Twenty seven of the included studies were case-control and one was a prospective cohort study. Eight of the studies indicated breastfeeding has a protective role against the development of T1D. Seven additional studies emphasized that a short period or absence of breastfeeding could be a risk factor for T1D development. The results of this systematic review indicate a short duration and/or a lack of breastfeeding may constitute a risk factor for the development of T1D later in life.

Smoking status in relation to serum folate and dietary vitamin intake

ObjectiveCigarette smoke itself is an abundant source of free radicals and a major cause of oxidative stress, to which plasma antioxidants function as a vital protective and counterbalancing mechanism. The objective of this study was to investigate into the relationship between smoking status and serum and dietary micronutrient concentrations.DesignCross-sectional studySubjects – Setting502 farmers from the Valley of Messara in Crete were randomly selected and examined. Complete three-day and 24-hr recall questionnaires were collected along with anthropometrical, physical activity and clinical data from all participating subjects.ResultsAfter adjusting for age, gender and number of fasting days adhered to per year, current smokers were found to have a lower dietary intake of vitamin C (112.1 mg vs. 136.4 mg, p = 0.03), fibre (16.6 g vs. 19.1 g, p = 0.006) and fruits and vegetables (339 g vs. 412 g, p = 0.014), while dietary vitamin B1 intake was found to be higher (1.7 mg vs. 1.4 mg, p = 0.02) in comparison to non/ex smokers. Dietary intake of meat, folate and vitami A, E, B2, B6 and B12 did not differ between the groups. Controlling age, gender, fasting days and dietary micronutrient intake, serum folate levels were found to be lower among smokers (geometric mean 15.3 nmol/L vs. 17.7 nmol/L, p = 0.023), while serum iron and vitamin B12 levels were not affected by smoking status.ConclusionCurrent smoking status affects dietary nutrient intake as well as plasma folate levels. The above coherence between antioxidant depletion and reduced antioxidant intake may predispose smokers to the premature development of tobacco related mortality and morbidity.

Two-year trends and predictors of e-cigarette use in 27 European Union member states

Objective This study assessed changes in levels of ever use, perceptions of harm from e-cigarettes and sociodemographic correlates of use among European Union (EU) adults during 2012–2014, as well as determinants of current use in 2014. Methods We analysed data from the 2012 (n=26 751) and 2014 (n=26 792) waves of the adult Special Eurobarometer for Tobacco survey. Point prevalence of current and ever use was calculated and logistic regression assessed correlates of current use and changes in ever use, and perception of harm. Correlates examined included age, gender, tobacco smoking, education, area of residence, difficulties in paying bills and reasons for trying an e-cigarette. Results The prevalence of ever use of e-cigarettes increased from 7.2% in 2012 to 11.6% in 2014 (adjusted OR (aOR)=1.91). EU-wide coefficient of variation in ever e-cigarette use was 42.1% in 2012 and 33.4% in 2014. The perception that e-cigarettes are harmful increased from 27.1% in 2012 to 51.6% in 2014 (aOR=2.99), but there were major differences in prevalence and trends between member states. Among those who reported that they had ever tried an e-cigarette in the 2014 survey, 15.3% defined themselves as current users. Those who tried an e-cigarette to quit smoking were more likely to be current users (aOR=2.82). Conclusions Ever use of e-cigarettes increased during 2012–2014. People who started using e-cigarettes to quit smoking tobacco were more likely to be current users, but the trends vary by country. These findings underscore the need for more research into factors influencing e-cigarette use and its potential benefits and harms.

Environmental tobacco smoke exposure in motor vehicles: a preliminary study.

Environmental tobacco smoke (ETS) contains over 3000 chemicals of which at least 50 are known or suspected to be human carcinogens, while over 200 are regarded as poisonous.1,2 Although passive smoking often occurs in private and public workplaces, with extensive research already conducted in hospitality venues, casinos, airplanes, airports and homes, to our knowledge there are insufficient data (if any) published on motor vehicle secondhand smoke (SHS) levels and no comparisons have been made with other areas where people are involuntarily exposed to ETS. Measurements of airborne respiratory particles under 2.5 μm (RSP2.5) in diameter were made using the TSI SidePak AM510 Personal Air Monitor during March 2005 in Crete, Greece. Respiratory particles of this size are not specific …

Poly-tobacco use among adults in 44 countries during 2008-2012: Evidence for an integrative and comprehensive approach in tobacco control

INTRODUCTION The concurrent use of multiple tobacco products (i.e., poly-tobacco use) might hinder efforts to reduce overall tobacco use, particularly considering that use of some non-cigarette tobacco products may be popular in some regions due to social, cultural, or economic reasons. This study assessed poly-tobacco use patterns among persons aged ≥15 years old from 44 countries. METHODS Data from 44 countries in all six World Health Organization regions were obtained from the 2008 to 2012 Global Adult Tobacco Surveys (n=19 countries), and the Special Eurobarometer 385 (77.1) survey, 2012 (n=25 countries). Correlates of poly-tobacco use were assessed using multivariate logistic regression analyses (p<0.05). RESULTS Overall prevalence of poly-tobacco use ranged from 0.8% (Mexico) to 11.9% (Denmark). In 28 countries, 20% or more of current smokers of manufactured cigarettes concurrently used at least one other tobacco product and this proportion was highest in India (66.2%) and lowest in Argentina (4.4%). After adjusting for other factors, the likelihood of being a poly-tobacco user among all respondents was lower among females (aOR=0.09; 95% CI: 0.08-0.11), and among respondents from upper-middle-income (aOR=0.53, 95% CI: 0.43-0.66), and lower-middle-income countries (aOR=0.64; 95% CI: 0.51-0.81) compared to high-income countries. Increased likelihood of poly-tobacco use was observed among respondents from the South-East Asian region compared to those from the European region (aOR=1.58, 95% CI: 1.35-1.85), as well as among respondents aged ≥65 years (aOR=2.10; 95% CI: 1.73-2.54), compared to those aged <25 years. CONCLUSIONS The pattern of tobacco use varied widely, underscoring the need for intensified efforts towards implementing policies that address all tobacco products, not only manufactured cigarettes.