Examining the impact of flavored e-cigarettes on adult smokers: insights from a three-month experimental study
By Jessica Zdinak
Much ink has been devoted to the dichotomy presented by electronic nicotine-delivery systems (ENDS)—are they a friend or a foe?
For several years now, we have seen a surge of a variety of different e-cigarette products, overrunning the U.S. commerce both legally and illegally. The question remains for some, including our regulator: Do they serve as an alternative to traditional combustible cigarettes, or do they serve as an initiator for youth and young adults? This dichotomy revolves heavily around the authorization of and use of flavored e-cigarette/e-liquid products.
Continuously, and in my opinion, rightfully so, the U.S. Food and Drug Administration’s Center for Tobacco Products (CTP) presents manufacturers with marketing denial orders that state things like “… your PMTA lacks sufficient evidence demonstrating that your flavored ENDS will provide a benefit to adult users that would be adequate to outweigh the risks to youth.” To demonstrate this, a reliable and robust study must be conducted. “Reliable and robust” means different things with each of the different scientific areas contained within an application. For the behavioral sciences, it means using a design that inherently has a level of methodological and statistical control, such as a randomized control trial, known in our scientific area as a “between-subjects experimental design.”
To address the CTP’s concerns and gain a better understanding of the effects of flavored e-cigarettes, the research team at Applied Research and Analysis Company (ARAC) conducted a three-month randomized experimental study. This study was sponsored by Accorto Regulatory Solutions, in conjunction with Freenoms, an e-liquid manufacturer and subsidiary of Lotus Vaping Technologies, creator of the Nomenons e-liquid. In this article, we will explore the key findings and insights from this study, shedding light on how flavored e-cigarettes may influence adult smokers’ habits and vapes’ potential as a smoking cessation tool.
Study Context
The study, conducted by a team of experts led by ARAC Chief Research Officer Jessica Zdinak, was designed to provide evidence related to the public health impact of flavored e-cigarette products on adult smokers. The study’s design played a crucial role in ensuring the validity and reliability of the results. Expertise in behavioral science and research methodologies were instrumental in crafting the study’s plan, design and analysis. After a recent meeting with the CTP, it is acknowledged that ARAC’s key behavioral science framework meets the mark from a scientifically rigorous perspective. Here are just a few key aspects of ARAC’s study designs that underscore the importance of such expertise:
- Statistical power: The study’s design took into account statistical power, ensuring that there were enough participants to detect significant effects should differences or effects exist and not to detect such differences or effects should they not exist. (Think, “Can you generalize your results?”)
- Effect size considerations: Researchers considered effect size, an important factor in determining the practical significance of findings. (Think, “How generalizable are your results?”)
- Hypothesis generation: The study involved the formulation of hypotheses that guided the research, enabling a systematic investigation of the impact of flavored e-cigarettes on smoking behaviors.
- Awareness of behavioral factors: Researchers were keenly aware of the behavioral factors at play behind nicotine consumption, adding depth to the study’s approach.
Study Design
The study was conducted using a between-subjects randomized experimental design, which involved two conditions: one with flavored e-liquids and another with tobacco-tasting e-liquids. The primary dependent variables were cigarettes per day (CPD) and candidate product usage. The use of a randomized experimental design is a rigorous and reliable approach to investigate the effects of flavored e-cigarettes on smoking behaviors, as it minimizes bias and allows for causal inferences.
Following Institutional Review Board approval, participants were recruited from several locations across the U.S. They were then randomly assigned to one of two conditions: flavored candidate e-liquids or tobacco-tasting candidate e-liquids. Over a three-month time period, participants returned to facilities each month to select additional products as needed and to complete follow-up surveys. The follow-up surveys asked participants to specify their CPD over the past 30 days and the past 24 hours as well as their use of the candidate e-liquids. These responses were used for the primary analyses in which reduction and cessation were defined and analyzed as:
- computed reduction of 50 percent or more of cigarette stick usage from baseline to follow-up
- complete elimination of cigarette sticks
Results: Descriptive Insights
At the end of the three-month study, a total of 382 participants completed the final follow-up survey (n=181 in flavor condition; n=157 in tobacco-tasting condition). Using this data, we conducted both descriptive and inferential statistics. Coupled together, but with a focus on the inferential statistics, this study’s results offer valuable insights into the impact of flavored e-cigarettes on smoking behaviors.
- Flavors over time: The study tracked how participants’ preferences for specific e-liquid flavors did (or did not) change over the three-month study period.
2. CPD between conditions over time: The results show the descriptive differences in cigarettes smoked per day between the flavored and tobacco-tasting conditions over the course of the study.
3. CPD between conditions over time: The results show the inferential statistics assessing the experimental effect of flavors on CPD compared to tobacco-tasting. Specifically, the study found that the portfolio of flavored e-liquids led to a significant reduction in CPD compared to tobacco-tasting products. This suggests that flavor plays a role in encouraging smokers to cut down on their cigarette consumption.
4. Switching rates: The research examined the rates at which participants switched from smoking cigarettes to using e-cigarettes, with specific attention to the flavored e-liquids, which led to a higher quit/cessation rate than tobacco-tasting e-liquids.
5. Individual flavor assessments: The study explored how individual flavors affected CPD reduction and cessation, providing insights into the specific flavors that had the most significant impact. Specifically, different flavors had varying effects on CPD reduction and cessation, with some flavors showing statistically significant differences. This highlights the complexity of the relationship between flavor and smoking behaviors, such as reduction in CPD and cessation of combustible cigarettes.
Summary of Findings
In summary, the study found that flavored e-liquids had a positive impact on smoking behaviors among adult smokers. Specific findings include:
- CPD reduction: The portfolio of flavored e-liquids were associated with a statistically significant reduction in cigarettes smoked per day compared to tobacco-tasting products, suggesting that flavors encourage smokers to cut down on their cigarette consumption.
- Variability among flavors: The impact of flavored e-liquids on CPD reduction and smoking cessation varied among different flavors. Certain flavors had a more pronounced effect, highlighting the need to consider the specific flavor profiles when evaluating their impact on smoking behavior.
- Preference changes over time: Some participants’ preferences for specific flavors changed throughout the study, indicating that flavor appeal may evolve and influence its effectiveness in encouraging smokers to switch to e-cigarettes.
- Qualitative insights: Open-ended questions provided valuable qualitative insights into how flavors influenced participants’ perceptions and decisions to quit or reduce cigarette consumption. These insights offer a more comprehensive understanding of the relationship between flavor and smoking behavior.
Overall, the study’s findings underscore the complex interplay between flavored e-cigarettes and smoking behaviors among adult smokers. While some flavors show promise in reducing cigarette consumption and promoting switching, there is no one-size-fits-all approach, and individual preferences and perceptions play a significant role.
One of the most powerful aspects of science is replicability. If industry is serious about getting new products, including flavors, authorized for market, replicability of studies such as this one is fundamental to success. Let’s hope this study is just the first of many at building that library of rigorous scientific evidence that the CTP has been looking for.
