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PATH Study Findings Give Insight into Flavored Tobacco, Health Effects of E-Cigarettes, and Adult Use of Cigars and Hookah

Tobacco regulation is a dynamic field and the U.S. Food & Drug Administration (FDA) relies on a robust science base to develop regulations that improve public health. Below you can learn more about initial findings from the Population Assessment of Tobacco and Health (PATH) Study. This important study offers unique insights into youth use of flavored tobacco products, the health effects of e-cigarettes, and adult use of cigars and hookah. 

The PATH Study is longitudinal (meaning it continues to follow the same people over time) and provides FDA with detailed information to help the agency examine changes over time in the use of tobacco products. A collaboration between the National Institutes of Health (NIH) and FDA, it follows about 46,000 U.S. participants, tobacco users and non-users, ages 12 and over. Adults provide urine and blood samples, which help PATH Study researchers obtain more comprehensive information about the health effects of tobacco use. While the PATH Study will take years to complete, each wave of data collected can be used by researchers to conduct independent analysis on tobacco products and use. PATH Study baseline data collected during 2013-2014 has driven research and publications on the topics below.


Setting a Baseline about Adults and Youth Whom the Study Will Follow for Several Years

One of the FDA-funded publications on PATH Study data assessed overall tobacco product use and the behaviors and demographic characteristics associated with it. Researchers found that about 28 percent of U.S. adults and nearly nine percent of youth were current users of at least one type of tobacco product in 2013 and 2014.1 For youth, current tobacco use is defined as use at least once in the last 30 days. For adults, current tobacco use is defined as use every day or some days, except for current use of hookah, which is defined as every day, some days, weekly, or monthly. 

Approximately 40 percent of both youth and adult tobacco users engaged in use of multiple products.1 Among multiple tobacco product users, cigarettes and e-cigarettes together were the most common product combination.

“This study is among the first to identify a new use pattern – using multiple tobacco products. Forty percent of tobacco users, kids and adults alike, are using two or more products in every combination imaginable. That has huge implications for treatment, public education and policy alike.”
-- Andrew Hyland, PATH Study Principal Investigator, Roswell Park Cancer Institute

Data Add to the Evidence Base that Flavored Tobacco Products May Attract Young Users

The PATH Study strives to better understand what motivates youth and young adults to use tobacco. When asked why they use tobacco products, 79 percent of youth (aged 12 to 17) and 89 percent of young adults (aged 18 to 24) stated that they used a tobacco product because the product “comes in flavors that I like.”2

Percentage of Tobacco Users Who Use Because Product Comes in Flavors They Like

The PATH Study also asked participants whether the first tobacco product they used was flavored. This is another key question to help researchers understand how people initiate using tobacco. It was observed that 81 percent of youth and 86 percent of young adults who had ever used tobacco reported that their first product was flavored, versus 54 percent of adults aged 25 or older.2

Further, among youth who ever used tobacco, those who said that their first tobacco product was flavored had a 13 percent higher prevalence of current tobacco use a year later.2 And among adults who ever used tobacco, those who said that their first tobacco product was flavored had a 32 percent higher prevalence of current tobacco use a year later.2

The data from the PATH Study give us critical insights into adult and youth tobacco use of flavored tobacco products, adding to the evidence base that flavored tobacco products may attract young users and serve as starter products to established tobacco use.


Data Compare the Health Effects of E-Cigarettes and Cigarettes

Because some adult participants in the PATH Study were asked to provide blood and urine samples, researchers can measure the exposure to harmful chemicals experienced by people who only use e-cigarettes, only use cigarettes, use both products, and those who have never used tobacco. The study found that exclusive e-cigarette users were exposed to known toxicants, but at lower levels than cigarette smokers.3

The exposure to harmful chemicals was highest in dual users of e-cigarettes and cigarettes.3 In the study there were 792 dual users, compared with 247 users of e-cigarettes only.3 Dual users who were daily smokers were exposed to the highest concentrations of nicotine and toxicants.

Level of Exposure to Nicotine and NNK (A Carcinogen in CIgarette Smoke)


This figure shows the levels of exposure to nicotine and NNK in adults who smoked cigarettes only (2411 people), who smoked both cigarettes and e-cigarettes (793 people), who smoked e-cigarettes only (247 people) and who had never smoked (1,655 people). Exposure levels were measured with urine samples testing for biomarkers of nicotine and NNK (a potent carcinogen in cigarette smoke created when nicotine is burned.) The left graph shows levels of urinary nicotine (TNE2) measured in nmol per mg of creatinine, while the right graph shows urinary NNK measured in pg per mg of creatinine. The boxes show the middle 50 percent of values (also called the interquartile range); the line in the center of each box shows the median value; and the whiskers show the highest and lowest values. Outlier values are excluded for clarity.


Shedding Light on Patterns of Adult E-Cigarette Use 

While it is a high priority to study youth use of products like e-cigarettes, we also want to know more about adult use. PATH Study data provide us with more information about adults who currently use e-cigarettes. About 6 percent of participating adults used e-cigarettes. Among them, 42 percent used infrequently (0-2 of the past 30 days), 37 percent used moderately (more than 2 of the past 30 days), and 21 percent were daily users.4

Nearly 89 percent of daily e-cigarette users reported using e-cigarettes as a way of cutting down on cigarette smoking, compared with 82 percent of moderate users and 58 percent of infrequent users.4 Those who reported using rechargeable or refillable devices were more likely to report daily use.4 These findings provide more information on daily and non-daily e-cigarette users, including differences in their preferred device types and their cigarette smoking status.4 


Enriching our Knowledge Base of Cigar and Hookah Adult Users

Today, the cigar market is comprised of diverse products. Historically many studies have treated cigars as a single product type or provided limited information on how cigars were differentiated. However, the PATH Study collected detailed information according to cigar type, by using descriptions of product attributes and common brands and showing participants cigar images. Researchers looked at the PATH Study data to see if smokers of various types of cigars were exposed to different levels of toxins. Overall, the researchers found that daily cigar smokers had levels of some toxins that were similar to those of daily cigarette smokers. Based on a very small number of cigar smokers, exploratory analysis found that for some toxins, exposure levels to toxins were higher for daily filtered cigar smokers than for daily traditional cigar smokers or daily cigarillo smokers.

Various cigars

 
The PATH Study also provides data about the traditionally under-studied topic of hookah smoking. Of the adults who reported hookah smoking, about 11 percent used daily or weekly, 14 percent used monthly, 42 percent smoked every couple of months, and 34 percent smoked about once a year.6 Young adults were more likely to be frequent smokers: about 66 percent of the daily or weekly hookah smokers were aged 18-24.6 People who smoked hookah more frequently tended to be younger and male, had more hookah refills per session, had fewer people sharing during sessions, and were more likely to own a hookah.6


Like Any Study, the PATH Study Has Limitations

While the PATH Study provides us with a wealth of information, it does have some limitations. For example, the first wave of data contains information about e-cigarette products that were available and commonly used at that time and may differ from those on the current market. Products such as JUUL were not on the market or did not have a substantial market share during 2013-2014. In addition, there is always the potential for recall bias (the participant may not remember behavior or events accurately) in any self-report survey. 

Another consideration is estimates of youth tobacco use from the household-based PATH Study were generally lower than those from school-based national surveys such as the National Youth Tobacco Survey and Monitoring the Future, while they were similar to estimates from the household-based National Survey on Drug Use and Health. It is possible that surveys administered in a school-based environment could overestimate tobacco-use behaviors because of peer influences, while youth may under-report in a home-based survey out of fear that their parents will learn their answers.

Future data will help answer questions about how and why people start using tobacco, quit using it, start using it again after they’ve quit, and how they transition among multiple tobacco products. You can always find a list of recent publications on the bottom of the PATH Study Series page.


Additional Resources

1.    Kasza KA, et al. Tobacco-Product Use by Adults and Youths in the United States in 2013 and 2014. N Engl J Med. 2017;376(4). http://www.nejm.org/doi/full/10.1056/NEJMsa1607538#t=article. Accessed March 14, 2019.
2.    Villanti et al. Flavored tobacco product use in youth and adults: findings from the first wave of the PATH study (2013-2014). Am J Prev Med. 2017;53(2). https://doi.org/10.1016/j.amepre.2017.01.026. Accessed March 14, 2019.
3.    Goniewicz ML, Smith DM, Edwards KC, et al. Comparison of Nicotine and Toxicant Exposure in Users of Electronic Cigarettes and Combustible Cigarettes. JAMA NetwOpen. 2018;1(8). https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2718096. Accessed March 15, 2019.
4.    Coleman et al. Electronic cigarette use among US adults in the Population Assessment of Tobacco and Health (PATH) Study, 2013–2014. Tob Control. 2017;26. http://dx.doi.org/10.1136/tobaccocontrol-2016-053462. Accessed March 14, 2019.
5.    Chang CM, Rostron BL, Chang JT, et al. Biomarkers of Exposure Among U.S. Adult Cigar Smokers: Population Assessment of Tobacco and Health (PATH) Study Wave 1 (2013-2014). Cancer Epidemiol Biomarkers Prev. 2019; Feb 7. pii: cebp.0539.2018. doi: 10.1158/1055-9965. EPI-18-0539. [Epub ahead of print] PMID: 30733305 https://www.ncbi.nlm.nih.gov/pubmed/30733305. Accessed April 12, 2019.
6.    Robinson et al. Characteristics of Hookah Tobacco Smoking Sessions and Correlates of Use Frequency Among US Adults: Findings From Wave 1 of the Population Assessment of Tobacco and Health (PATH) Study. Nicotine Tob Res. 2017;20(6). https://doi.org/10.1093/ntr/ntx060.