Biomarkers of Inflammation and Oxidative Stress among Adult Former Smoker, Current E-Cigarette Users-Results from Wave 1 PATH Study

Comparing Adult Smokers Who Switched to JUUL versus Continuing Smokers: Biomarkers of Exposure and of Potential Harm and Respiratory Symptoms

OBJECTIVES

Real-world evidence on exposure to harmful and potentially harmful constituents (HPHCs) and on biological effects in cigarette smokers who switch to electronic nicotine delivery systems (ENDS) can inform the health effects of switching.

AIMS AND METHODS

This cross-sectional, observational study assessed adults who had smoked ≥10 cigarettes/day for ≥10 years, comparing 124 continuing cigarette smokers (Smokers) to 140 former smokers who switched to JUUL-brand ENDS exclusively for ≥6 months (Switchers). Assessments included biomarkers of exposure (BOEs) to select HPHCs, biomarkers of potential harm (BOPHs) related to smoking-related diseases, psychometric assessments of dependence on cigarettes and ENDS, respectively, and respiratory symptoms. Planned analyses compared geometric means, adjusted for demographic covariates; further analyses adjusted for additional lifestyle and smoking history covariates.

RESULTS

Nicotine levels were significantly higher in Switchers (median time switched = 3 years), who were unusually heavy users of JUUL. All other BOEs, including NNAL and HPMA3 (primary endpoints), were significantly lower in Switchers than Smokers. Most BOPHs (sICAM-1 [primary], and eg, white blood cell count, MCP1, HbA1c) were significantly lower in Switchers than Smokers; HDL was significantly higher. Switchers reported significantly lower dependence on JUUL than Smokers did on cigarettes, and respiratory symptom scores were significantly lower among Switchers than Smokers.

CONCLUSIONS

Compared to continuing smokers, smokers who switched to JUUL had substantially lower exposures to multiple HPHCs, favorable differences in markers of inflammation, endothelial function, oxidative stress, and cardiovascular risk, and fewer respiratory symptoms. These findings suggest that switching from cigarettes to JUUL likely reduces smokers' health risks.

IMPLICATIONS

Short-term confinement studies and randomized clinical trials demonstrate that adult smokers who switch completely to ENDS experience substantial reductions in exposure to many smoking-related toxicants. This study extends those findings to longer periods of switching to JUUL-brand ENDS (almost 3 years on average) under naturalistic use conditions in real-world settings and also found that switching to JUUL resulted in favorable differences in BOPHs more proximally related to smoking-induced disease, as well as in respiratory symptoms. Smokers who switch to ENDS reduce their exposure to toxicants, likely reducing their disease risk.

The Use of Electronic Cigarettes in Saudi Arabia: A Narrative Review

The use of electronic cigarettes (or "e-cigarettes") is spreading throughout the world. Population-level data from a number of countries indicate that e-cigarettes are used more by children and young adults than by the overall population. Although extensive research has been conducted in Western nations to better understand many aspects of e-cigarette usage among children and young adults, Middle Eastern nations have little data on this topic. The use of tobacco is detrimental to the health, finances, and national spirit of Saudi Arabia. More than 7,000 of its citizens die each year from diseases caused by tobacco use. Nevertheless, more than 20,000 youngsters and 3,352,000 adults smoke cigarettes each day. Similarly, the use of electronic cigarettes is on the rise, possibly as a result of aggressive publicity and marketing campaigns by manufacturers that appeal to the younger demographic. This review was undertaken through literature research to ascertain the usage and attitudes toward e-cigarette use among the Saudi population.

Racial and ethnic disparities in biomarkers of exposure and potential harm among U.S. adult exclusive e-cigarette users: 2013-2019

OBJECTIVE

Provide evidence on racial and ethnic differences in biomarkers of exposure from rising e-cigarette use among U.S. adults.

METHODS

Data were drawn from Waves 1-5 of the Population Assessment of Tobacco and Health study (September 2013-November 2019). Differences in biomarkers of exposure and potential harm (BOE/BoPH) across non-Hispanic (NH)-Whites, NH Blacks, Hispanic/Latinos, and NH others were examined using generalized estimation equations.

RESULTS

Among exclusive e-cigarette users, mean concentrations of BOEs/BoPHs were not significantly different across NH Blacks (n=97), NH others (n=122), and NH Whites (n=1062), after adjustment by wave, age, sex, education, exposure to the secondhand smoke, and the number of recent puffs. Compared to NH Whites, Hispanics (n=151) had lower concentrations of nicotine equivalents (0.5[0.2-1.7] vs. 15.5 [12.5-19.1] nmol/mg creatinine, p<.0001), cotinine (33.4[9.7-114.7] vs. 1008.3 [808.3-1257.9] ng/mg creatinine, p<.0001), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) (2.6[1.5-4.4] vs. 5.7 [4.9-6.6] pg/mg creatinine, p=.004), but similar concentrations of BOEs for heavy metals, polycyclic aromatic hydrocarbons, volatile organic compounds, and oxidative stress. Differences between Hispanics and NH Whites are expected, given different e-cigarette use profiles. Specifically, Hispanics were less likely to be daily vapers (49.4[35.1-63.8]% vs 81.3[77.7-84.5]%, p<.0001) and nicotine e-cigarette users (72.7 [64.0-79.9]% vs. 89.2 [86.4-91.5]%, p=.0002] and reported a lower number of recent puffs (mean[standard error]=16.7[3.6] vs. 28.6[2.0], p=.02] than their NH-White counterparts. Hispanic vapers were also less likely than NH Whites to have previously smoked cigarettes (49.7 [37.2-62.3]% vs. 88.5 [84.7-91.5]%, p<.0001]).

CONCLUSIONS

Hispanic vapers exhibited lower exposure to nicotine metabolites and carcinogens than their non-Hispanic White counterparts. The harm reduction potential from e-cigarette use are likely to be realized across diverse racial and ethnic groups.

The association between e-cigarette use or dual use of e-cigarette and combustible cigarette and prediabetes, diabetes, or insulin resistance: Findings from the National Health and Nutrition Examination Survey (NHANES)

BACKGROUND

Studies have established associations between combustible cigarette use and diabetes. However, there is limited evidence on the association between e-cigarette use or dual use of e-cigarettes and combustible cigarettes and diabetes.

METHOD

With cross-sectional data of 5101 U.S. adults from the National Health and Nutrition Examination Survey, this study examined how e-cigarette use or dual use was related to diabetes, prediabetes, or insulin resistance. The presence of diabetes or prediabetes was determined by fasting glucose level, hemoglobin A1C (HbA1c), or the use of prescribed medications. Insulin resistance was assessed by the homeostatic model (HOMA-IR). The independent association between e-cigarette use or dual use and outcomes was examined using weighted multivariable logistic regression models controlling for potential confounders.

RESULTS

Of all participants, 6.3% were current e-cigarette users and 17.1% were former e-cigarette users. In the fully adjusted model, e-cigarette use was not associated with prediabetes or diabetes (P>0.05). However, former e-cigarette users were 22% (95% CI: 1.00, 1.84) more likely to report higher HOMA-IR (Q3 vs Q1) than never e-cigarette users. Among ever combustible cigarette users, current e-cigarette users and former e-cigarette users were 63% (95% CI: 1.00, 2.91) and 64% (95% CI: 1.04, 2.59) more likely to report higher HOMA-IR than never e-cigarette users, respectively. There was no significant association between dual use and diabetes, prediabetes, or insulin resistance (P>0.05).

CONCLUSIONS

E-cigarette use may be associated with insulin resistance. Our findings may inform future tobacco control policies and longitudinal studies assessing insulin resistance associated with e-cigarette use.

Testicular tissue response following a 90-day subchronic exposure to HTP aerosols and cigarette smoke in rats

Background

Researches have shown that chronic inhalation of cigarette smoke (CS) disrupts male reproductive system, but it is unclear about the mechanisms behind reproductive damages by tobacco toxicants in male rats. This study was designed to explore the effects of heated tobacco products (HTP) aerosols and CS exposure on the testicular health of rats.

Materials and Methods

Experiments were performed on male SD rats exposed to filtered air, HTP aerosols at 10 μg/L, 23 μg/L, and 50 μg/L nicotine-equivalent contents, and also CS at 23 μg/L nicotine-equivalent content for 90 days in five exposure groups (coded as sham, HTP_10, HTP_23, HTP_50 and Cig_23). The expression of serum testosterone, testicular tissue inflammatory cytokines (IL-1β, IL-6, IL-10, TNF-α), reactive oxygen species (ROS), superoxide dismutase (SOD) and malondialdehyde (MDA), NLRP3 inflammasome-related mRNAs and proteins (NLRP3, ASC, and Caspase-1), the degree of pyroptosis and histopathology were investigated.

Results

The results demonstrated that HTP_50 and Cig_23 caused varying degrees of oxidative damage to rat testis, resulting in a decrease of sperm quantity and serum testosterone contents, an increase in the deformity rate, expression levels of proinflammatory cytokines, and NLRP3 inflammasome-related mRNA, and an increase in the NLRP3, ASC, and Caspase-1-immunopositive cells, pyroptosis cell indices, and histopathological damage in the testes of rats. Responses from the HTP_10 and HTP_23 groups were less than those found in the above two exposure groups.

Conclusion

These findings indicate that HTP_50 and Cig_23 induced oxidative stress in rat testes, induced inflammation and pyroptosis through the ROS/NLRP3/Caspase-1 pathway, and destroyed the integrity of thetesticular tissue structure.

The cardiovascular consequences of electronic cigarette smoking: a narrative review

INTRODUCTION

E-cigarettes have emerged as a popular alternative to traditional tobacco smoking in recent years. Despite their growing popularity, concerns have arisen regarding the cardiovascular implications of e-cigarette use.

AREAS COVERED

This narrative review aims to highlight the latest evidence on the impact of e-cigarettes on cardiovascular health.

EXPERT OPINION

Numerous studies have demonstrated that e-cigarette use can lead to acute adverse cardiovascular effects. Inhalation of e-cigarette aerosols exposes users to a wide range of potentially harmful substances that have been implicated in critical pathophysiologic pathways of cardiovascular disease, namely endothelial dysfunction, oxidative stress, inflammation, sympathetic overdrive, and arterial stiffness. While long-term epidemiological studies specifically focusing on the cardiovascular effects of e-cigarettes are still relatively scarce, early evidence suggests a potential association between e-cigarette use and an increased risk of adverse cardiovascular events. However, it is essential to recognize that e-cigarettes are relatively new products, and the full extent of their long-term cardiovascular impact has not been fully elucidated. In the meantime, promoting tobacco cessation strategies that are evidence-based and regulated, along with rigorous monitoring of e-cigarette use patterns and associated health outcomes, are essential steps in safeguarding cardiovascular health in the face of this emerging public health challenge.

US FDA public meeting: identification of concepts and terminology for multicomponent biomarkers

The US FDA convened a virtual public workshop with the goals of obtaining feedback on the terminology needed for effective communication of multicomponent biomarkers and discussing the diverse use of biomarkers observed across the FDA and identifying common issues. The workshop included keynote and background presentations addressing the stated goals, followed by a series of case studies highlighting FDA-wide and external experience regarding the use of multicomponent biomarkers, which provided context for panel discussions focused on common themes, challenges and preferred terminology. The final panel discussion integrated the main concepts from the keynote, background presentations and case studies, laying a preliminary foundation to build consensus around the use and terminology of multicomponent biomarkers.

Understanding heterogeneity among individuals who smoke cigarettes and vape: assessment of biomarkers of exposure and potential harm among subpopulations from the PATH Wave 1 Data

Introduction

People who both smoke cigarettes and vape are often considered as a homogenous group even though multiple subgroups may exist. We examined biomarkers of exposure (BOE) and biomarkers of potential harm (BOPH) to differentiate between subgroups of people who smoke and vape based on PATH Study Wave 1 (2013–2014) data.

Methods

We compared people who only smoke cigarettes everyday (Group A, n = 2442) and people who only vape everyday (Group C, n = 169) against people who smoke and vape segmented into subgroups of people who frequently smoke and vape (Group B1, n = 169), frequently smoke and infrequently vape (Group B2, n = 678), frequently vape and infrequently smoke (Group B3, n = 57), and infrequently smoke and vape (Group B4, n = 66). Eighteen BOEs (representing exposure to TSNAs, nicotine, heavy metals, PAHs, and volatile organic compounds) and four BOPHs (representing inflammation and oxidative stress) were compared within the subgroups.

Results

Levels of many BOEs/BOPHs were higher among Group B2 relative to Groups B1, B3, and B4. Compared to Group A, many BOEs were significantly lower in Groups B3 (15/18) and B4 (17/18), and some BOEs were higher among B2 (4/18). Compared to Group C, significantly lower BOEs were observed for Group B4 (2/18).

Conclusions

Overall, the levels of BOEs and BOPHs in people who smoke and vape are associated with frequency of cigarette smoking. Our findings indicate that not all people who smoke and vape are the same, and tobacco product use frequency should be considered when categorizing people who smoke and vape.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12954-022-00673-x.

Cardiovascular Outcomes among Combustible-Tobacco and Electronic Nicotine Delivery System (ENDS) Users in Waves 1 through 5 of the Population Assessment of Tobacco and Health (PATH) Study, 2013-2019

BACKGROUND

Prior studies have not clearly established risk of cardiovascular disease (CVD) among smokers who switch to exclusive use of electronic nicotine delivery systems (ENDS). We compared cardiovascular disease incidence in combustible-tobacco users, those who transitioned to ENDS use, and those who quit tobacco with never tobacco users.

METHODS

This prospective cohort study analyzes five waves of Population Assessment of Tobacco and Health (PATH) Study data, Wave 1 (2013-2014) through Wave 5 (2018-2019). Cardiovascular disease (CVD) incidence was captured over three intervals (Waves 1 to 3, Waves 2 to 4, and Waves 3 to 5). Participants were adults (40+ years old) without a history of CVD for the first two waves of any interval. Change in tobacco use status, from exclusive past 30 day use of any combustible-tobacco product to either exclusive past 30 day ENDS use, dual past 30 day use of ENDS and combustible-tobacco, or no past 30 day use of any tobacco, between the first two waves of an interval was used to predict onset of CVD between the second and third waves in the interval. CVD incidence was defined as a new self-report of being told by a health professional that they had congestive heart failure, stroke, or a myocardial infarction. Generalized estimating equation (GEE) analyses combined 10,548 observations across intervals from 7820 eligible respondents.

RESULTS

Overall, there were 191 observations of CVD among 10,548 total observations (1.7%, standard error (SE) = 0.2), with 40 among 3014 never users of tobacco (1.5%, SE = 0.3). In multivariable models, CVD incidence was not significantly different for any tobacco user groups compared to never users. There were 126 observations of CVD among 6263 continuing exclusive combustible-tobacco users (adjusted odds ratio [AOR] = 1.44; 95% confidence interval (CI) 0.87-2.39), 15 observations of CVD among 565 who transitioned to dual use (AOR = 1.85; 0.78-4.37), and 10 observations of CVD among 654 who quit using tobacco (AOR = 1.18; 0.33-4.26). There were no observations of CVD among 53 who transitioned to exclusive ENDS use.

CONCLUSIONS

This study found no difference in CVD incidence by tobacco status over three 3 year intervals, even for tobacco quitters. It is possible that additional waves of PATH Study data, combined with information from other large longitudinal cohorts with careful tracking of ENDS use patterns may help to further clarify this relationship.