E-cigarettes and Tobacco Exposure Biomarkers among American Indian Smokers

Variation in Nicotine Metabolization According to Biological Factors and Type of Nicotine Consumer

This study aims to describe the nicotine metabolite ratio among tobacco smokers and electronic cigarette (e-cigarette) users and nonusers. We analyzed pooled data from a longitudinal and a cross-sectional study of the adult population from the city of Barcelona. The final sample included information on 166 smokers, 164 e-cigarettes users with nicotine, 41 e-cigarette users without nicotine, 95 dual users (users of both products), and 508 nonusers. We used log-linear models to control for the potential confounding effect of the daily number of cigarettes smoked. Salivary nicotine metabolic rate assessment included the rate of nicotine metabolism (cotinine/nicotine) and the nicotine metabolite ratio (trans-3′-hydroxycotinine/cotinine). Exclusive users of e-cigarette without nicotine have the lowest rate of nicotine metabolism (Geometric mean: 0.08, p-values < 0.001) while cigarette smokers have the highest (Geometric mean: 2.08, p-values < 0.001). Nonusers have lower nicotine metabolic rate than cigarette smokers (Geometric means: 0.23 vs. 0.18, p-value < 0.05). Younger individuals (18−44 years) have a higher rate of nicotine metabolism than older individuals (45−64 years and 65−89) (Geometric means: 0.53 vs. 0.42 and 0.31, respectively, p-values < 0.01) and individuals with lower body mass index (21−25 kg/m2) have a higher rate of nicotine metabolism than the rest (26−30 kg/m2 and 31−60 kg/m2) (Geometric means: 0.52 vs. 0.35 and 0.36, respectively-values < 0.01). Nicotine metabolic rates are useful biomarkers when reporting smoking status and biological differences between individuals.

Perceptions of Smoking and Vaping on Weight Control Among Adult American Indians Who Smoke

Interest in electronic cigarette (EC) use, or vaping, to help control weight is increasing. Many American Indian (AI) populations have a high prevalence of smoking, obesity, and EC use, but their perceptions of EC use for weight control are unknown. In Oklahoma in 2016, 375 AI adults who smoke completed a survey including perceptions about smoking and EC effects on weight control. Only 24% believed that smoking helps control weight, and 8% believed that vaping helps control weight. Perceptions differed by EC use, with ever users more often than never users perceiving that smoking (30% vs 12%, respectively; p < .01) and vaping (10% vs 5%; p = .04) help to control weight. Sex, age group (18-44 years vs 45 + years), education (high school graduate/equivalent vs less than high school), smoking cessation attempt in past year, and likelihood to quit in 6 months were not associated with weight control perceptions for either smoking or vaping. Uncertainty regarding EC effects on weight control was less common among EC ever users compared to never users (41% vs 53%, respectively; p = .04). Most people who did not believe or were uncertain that smoking controls weight also did not believe or were uncertain that vaping controls weight. However, only a minority (29%) of people who believed smoking controls weight also believed that vaping controls weight. Among adult AI who smoke, both smoking and vaping were infrequently perceived as helping to control weight, but such perceptions were reported more frequently among those who ever used ECs.

Use of Potentially Reduced Exposure Tobacco Products Among American Indian Smokeless Tobacco Users: Associations With Cessation Behaviors and Cotinine Levels

OBJECTIVES

American Indian/Alaska Native (AI/AN) adults use smokeless tobacco products (eg, chewing and dip tobacco) more often than other racial/ethnic groups do. Although US adults increasingly use potentially reduced exposure tobacco products (PREPs), such as electronic cigarettes and snus, no studies have examined the use of PREPs among AI/AN smokeless tobacco users. We examined associations between current PREPs use and smokeless tobacco-related measures, including cessation attempts and cotinine levels, in a sample of American Indian adults who currently use smokeless tobacco.

METHODS

We collected survey and tobacco biomarker data from 299 adult American Indian smokeless tobacco users at Cherokee Nation health care facilities and events in 2016 and 2017. We used multivariable analyses to determine associations between current PREPs use and smokeless tobacco-related characteristics.

RESULTS

Current PREPs users were younger, less likely to be married or living with a partner, less likely to report a chronic medical condition, and more likely to report other tobacco use than PREPs nonusers. Among participants with annual household incomes ≤$30 000, current PREPs users were less likely than PREPs nonusers to report a definite desire to quit smokeless tobacco (P = .02). PREPs use was not associated with planning to quit smokeless tobacco, past 12-month smokeless tobacco quit attempts, amount of smokeless tobacco used per week, cotinine levels, or scores on the Fagerström Test for Nicotine Dependence-Smokeless Tobacco.

CONCLUSIONS

Our study suggests that American Indian smokeless tobacco users may not be using PREPs as a smokeless tobacco cessation aid. Future studies should take this finding into consideration when evaluating the role of PREPs use in smokeless tobacco cessation and in total tobacco cessation in this population.

Impact of e-cigarette use among a cohort of American Indian cigarette smokers: associations with cigarette smoking cessation and cigarette consumption

INTRODUCTION

Despite American Indian/Alaska Native (AI/AN) people having the highest prevalence of cigarette smoking nationwide, few studies have evaluated e-cigarette use among AI/AN adults who smoke. The primary objective of this observational pilot cohort study was to determine if e-cigarette use is associated with cigarette smoking cessation or reduction among adult AI individuals who smoke.

METHODS

In 2016, we collected baseline survey and biomarker data among AI adults who smoke. The survey included questions about cigarette consumption and use of e-cigarettes and biomarkers, such as salivary cotinine markers and exhaled carbon monoxide. After 18 months, we repeated data collection, and asked about changes in cigarette smoking status and cigarettes per day (CPD). Comparisons between groups were performed using the χ² test, Fisher's exact test or Wilcoxon rank-sum test.

RESULTS

Of 375 baseline participants, 214 (57.07%) returned for follow-up and were included in analyses. Of these, 20 (9.3%) reported having stopped cigarette smoking and had biochemical verification of cigarette smoking abstinence. Among those who quit smoking, 15% were baseline e-cigarette users; while among those who continued to smoke at follow-up, about 11% were baseline e-cigarette users. This difference was not statistically significant (p=0.48). Among all those who continued to smoke at follow-up, there was no overall decrease in CPD, nor a significant difference in change in CPD between baseline e-cigarette users and non-users (p=0.98).

CONCLUSIONS

E-cigarette use at baseline was not associated with smoking cessation or a change in CPD in this cohort of AI adults who smoke after an 18-month follow-up period.

Vaping patterns, nicotine dependence and reasons for vaping among American Indian dual users of cigarettes and electronic cigarettes

BACKGROUND

The American Cancer Society discourages the dual use of electronic cigarettes (ECs) and cigarettes because such use has not resulted in reduced exposures to the harmful effects of smoking. American Indian (AI) people have the highest prevalence of smoking and of EC use in the United States, but very little is known about dual EC and cigarette use in AI communities.

METHODS

In 2016, 375 adult AI in Oklahoma who smoked cigarettes completed a survey about EC use (vaping). We describe vaping patterns, nicotine dependence, and reasons for EC use among the subset of 44 (12%) current dual EC users. To differentiate habitual EC users from occasional or merely curious users, we defined dual use as using ECs on some days or every day in the past 30 days.

RESULTS

About one-third of dual users vaped ten or more times daily. About two-thirds used a tank product. Eleven percent used ECs without nicotine and another 9% were unsure of the nicotine content. A minority (40%) enjoyed vaping more than smoking, and most (76%) would smoke first on days they did both. Thirty-one percent vaped within 5 min of waking and another 24% within 30 min. Although the two-item heaviness of use index did not differ significantly between smoking and vaping, the ten-item Penn State Dependence Index (PSDI) suggested greater dependence on smoking than vaping (11.02 vs. 6.42, respectively; p < .0001). The most common reasons for vaping were to reduce smoking (79%), enjoyment of flavors (78%), and ability to vape where smoking is not allowed (73%). Perceptions of less harm to others (69%) or to self were the next most common (65%). Fewer than half used ECs to reduce stress, for affordability, or because others used them.

CONCLUSIONS

Nearly 20% of dual users used ECs either without nicotine or without knowing if the product contained nicotine. The PSDI indicated greater dependence on smoking than vaping. Reasons for vaping were nearly equal between smoking reduction and enjoying flavors. Understanding patterns of dual use will inform future efforts to address nicotine dependence for AI communities with high prevalence of smoking.

Dual Versus Never Use of E-Cigarettes Among American Indians Who Smoke

INTRODUCTION

Many American Indian communities have a high prevalence of smoking and e-cigarette use, but factors associated with their dual use are rarely studied.

METHODS

In 2016, a total of 375 American Indian adults who smoke completed paper surveys regarding cigarette and e-cigarette use and provided saliva for cotinine levels. In 2018, cross-sectional analyses were performed, comparing dual users (12%), defined as using e-cigarettes on some or every day for the past 30 days, with never users of e-cigarettes (37%).

RESULTS

Compared with never users, dual users were younger, more often reported history of depression (56% and 29%, respectively; p<0.01) and family history of smoking-related disease (77% and 59%, respectively; p<0.05), had lower harm perceptions of e-cigarettes (27% and 47%, respectively; p<0.01) or vapor (14% and 35%, respectively; p<0.01), and more often perceived e-cigarettes as cessation aids (75% and 16%, respectively; p<0.01) and as less harmful than cigarettes (70% and 17%, respectively; p<0.01). Dual users were less often uncertain/unknowing about e-cigarette benefits or harms (p<0.01) and more often reported likelihood to quit smoking (49% and 24%, respectively; p<0.01) and prior attempt to quit smoking, ever (89% and 67%, respectively; p<0.01) or in the past year (55% and 32%, respectively; p=0.01). Cigarette consumption and cotinine levels did not differ between groups. Dual users more often tried other nicotine products (p<0.02) and more often lived with a vaping partner/spouse (45% and 6%, respectively; p<0.01).

CONCLUSIONS

Dual users perceived e-cigarettes as less harmful than cigarettes and more as cessation aids than cigarette-only users did, but cigarette consumption did not differ between groups. Whether e-cigarettes will reduce smoking-related disparities among American Indian people remains undetermined.