Heated tobacco products (HTPs) are devices that heat processed tobacco rather than burn the tobacco directly in order to generate a nicotine aerosol for inhalation. Different HTP devices use different heating sources, including electric energy via a battery or carbon tip that is lit with a match or lighter. The HTP system has three common components: (1) an insert (such as stick, capsule, and pods) that contains the processed tobacco, (2) a way to heat the tobacco (i.e., battery or carbon tip), and (3) a charger for electrically heated devices [1
]. While not an entirely new concept, HTPs have been around for 30 years, with the introduction of Premier by R. J. Reynolds Tobacco Company in 1988 and Accord by Philip Morris (PMI) in 1997 [2
]. More recently, HTPs have been marketed and promoted by the cigarette companies as safer alternative to combustible cigarettes [4
]. Alongside these marketing campaigns, awareness of HTPs has reached significant levels in many countries from 2015 to 2017 (e.g., 48.0% of Japanese adults [5
], 38.1% of South Korean young adults [6
], 19.5% of Italian adults [7
], and 9.3% of adults in Great Britain had heard of HTPs [1
]). In the United States (US), two studies have suggested considerable awareness of HTPs among the adult population, varying from 5.2% to 12.4% in 2016 to 2017 [8
Due in part to lenient national tobacco control measures [10
] and the prohibition of electronic nicotine delivery system (ENDS) marketing [11
], Japan has been a testing ground for HTPs. IQOS, marketed by PMI, was first introduced in 2014, followed in 2016 by the launches of Ploom TECH by Japan Tobacco International (JTI) and glo by British American Tobacco (BAT) [11
]. According to market analyst reports, Japan has the most developed HTP market of all countries worldwide, accounting for 85% of HTP sales in 2018 [12
]. This status has been further cemented by the subsequent release of newer generation HTPs and flavor varieties for tobacco-containing inserts in the Japanese market (Table 1
PMI has claimed that IQOS attained 15.5% of the overall tobacco market after just four years of its introduction [12
]. While the prevalence of cigarette smoking in Japan steadily decreased over the past decade [17
], the introduction of HTPs has raised concerns in achieving further tobacco control progress. HTPs might attract tobacco-naïve individuals, especially youth, with their high-tech appearance and reduced risk claims, both of which align with Japanese cultural norms around cleanliness and respect for others [18
]. On the other hand, if a significant proportion of cigarette smokers switched to HTPs completely, the associated decline in smoking prevalence may confer substantial benefit towards the public’s health. HTPs promoted by the three major tobacco companies (PMI, JTI, and BAT) may employ a variety of marketing strategies to appeal to different sociodemographic user groups. Indeed, differentiated marketing strategies for cigarette smoking have disproportionately appealed to population subgroups, including youth and young adults [21
], women [23
], minorities [24
], and health-concerned smokers [21
Most of the data available on the use of HTPs in Japan has come from manufacturers and market analysts. Given the apparent popularity of HTPs in Japan, we felt it was important to independently assess the prevalence and characteristics of users. In this paper, we describe sociodemographic characteristics, product use patterns, device brand and flavor preferences among users of HTPs in Japan, including never smokers, former smokers, and current smokers (dual users).
3.1. Prevalence of HTP Use and User Characteristics
shows the characteristics of the study population stratified by smoking status. The overall prevalence of HTP use was 2.7% (95% CI: 2.4–3.0%), while the prevalence of exclusive HTP use was 0.9% (95% CI: 0.7–1.1%). Among HTP users, 67.8% (95% CI: 63.1–72.2%), 25.0% (95% CI: 20.8–29.8%), and 1.0% (95% CI: 0.4–2.0%) were current smokers, former smokers, and never smokers, respectively. A greater proportion of HTP users were male, aged 40–59, and belonged to the high-income (>6,000,000 Japanese Yen) group. The majority of HTP users who were current smokers and former smokers fell within the high education category (i.e., undergraduate or postgraduate degree).
3.2. Patterns of HTP Use and Cigarette Smoking
The majority of HTP users (63.4%; 95% CI: 58.9–67.6%) reported using HTPs on a daily basis, with daily use being more common among exclusive HTP users (88.3%; 95% CI: 80.5–93.2%). While the majority of HTP users among the three smoking status categories reported daily use of HTP (current smokers: 51.5%, 95% CI: 46.7–56.3%; former smokers: 86.9%, 95% CI: 77.2–92.9%; and never smokers: 100%), current smokers had the highest percentage for weekly and monthly use of HTP (19.1%, 95% CI: 16.1–22.5%; and 29.4%, 95% CI: 24.4–34.9%, respectively). HTP users most commonly reported that they use HTP 6–30 min after waking up (current HTP users: 33.8%, 95% CI: 29.7–38.1%; and exclusive HTP users: 40.9%, 95% CI: 32.2–50.1%).
The number of tobacco-containing inserts per day (median, (interquartile range)) for all HTP users and exclusive HTP users was 10.0 (2.8–15.0) and 10.0 (5.0–18.0). While the number of tobacco-containing inserts per day was not significantly different for HTP users who were former smokers and never smokers (former smokers: 10.0 (5.0–18.0) and never smokers: 15.0 (3.0–20.0)), it was significantly lower for those who also concurrently smoked cigarettes (7.0 (1.4–15.0); both p < 0.05).
presents HTP use patterns and flavor preferences according to device brand preference. Although daily use was the most prevalent pattern across users of three device brands (IQOS: 69.6%, 95% CI: 63.9–74.7%; glo: 60.1%, 95% CI: 48.2–70.9%; and Ploom TECH: 49.1%, 95% CI: 39.9–58.3%), Ploom TECH users had the highest percentage of weekly and monthly HTP users compared to the other two device brands (weekly: 20.2%, 95% CI: 14.6–27.3%; monthly: 30.7%, 95% CI: 22.4–40.5%). IQOS users most frequently reported 6–30 min for time-to-first HTP use (36.6%, 95% CI: 31.3–42.3%), while glo and Ploom TECH users most often reported more than 60 min (40.3%, 95% CI: 29.6–52.0%; and 46.5%, 95% CI: 37.4–55.8%, respectively). The number of tobacco-containing inserts per day for IQOS, glo, and Ploom TECH users were 10.0 (5.0–18.0), 10.0 (5.0–18.0), and 1.0 (0.7–5.0), respectively. There was a statistically significant difference for the number of tobacco-containing inserts per day between Ploom TECH users and IQOS users, along with Ploom TECH and glo users (both p
3.3. Device Brand Preference
IQOS was the most prevalent device among current HTP users (64.5%, 95% CI: 60.3–68.6%), followed by Ploom TECH (21.1%, 95% CI: 17.8–24.8%), and glo (14.4%, 95% CI: 11.7–17.5%). Among exclusive HTP users, the pattern of device brand preference was similar (IQOS: 74.0%, 95% CI: 65.3–81.1%; Ploom TECH: 17.8%, 95% CI: 11.8–25.9%; and glo: 8.2%, 95% CI: 4.6–14.2%). There was a statistically significant association between device brand preference and HTP use by smoking status. IQOS was the most common HTP device brand reported by current smokers, former smokers, and never smokers (current smokers: 60.1%, 95% CI: 55.3–64.7%; former smokers: 74.8%, 95% CI: 64.1–83.2%; and never smokers: 100%).
shows the device brand preference by various demographic characteristics. There was an association between device brand preference and age group (Figure 1
A). While IQOS was the most preferred device across all age groups, its use tended to be lower among older age groups compared to those aged 20 to 29. Conversely, Ploom TECH use was higher among older age groups, with 41.5% (95% CI: 29.9–54.2%) of those aged 60 and older using it (Figure 1
A). IQOS was the most preferred device among both males and females (Figure 1
B). IQOS also was the most preferred device brand across the income and education categories, while glo was the least preferred device brand (Figure 1
The association between sociodemographic characteristics and each device brand among current HTP users (adjusted for frequency of HTP use) can be seen in Table 4
. Compared to those aged 20–29, those aged 30–39, 40–59, and aged 60 and older had lower odds (adjusted odds ratios (95% CI)) of using IQOS (30–39: 0.46 (0.24–0.86), 40–59: 0.36 (0.20–0.66), and aged 60 and older: 0.20 (0.09–0.43)) but higher odds of using Ploom TECH (40–59: 3.69 (1.61–8.92) and aged 60 and older: 6.32 (2.44–17.33)). No other sociodemographic characteristics were noted to be consistently associated with each device brand use. Compared to daily HTP users, those who use HTP weekly and monthly had lower odds of using IQOS (weekly: 0.61 (0.39–0.95); monthly: 0.49 (0.29–0.83)). In contrast, weekly and monthly HTP users had higher odds of using Ploom TECH (weekly: 1.89 (1.12–3.17); monthly: 2.12 (1.19–3.76)).
The most common reason for choosing IQOS was “used by friend” (68.1%, 95% CI: 62.8–73.0%), while for glo and Ploom TECH it was the “perceived reduction in health risk compared to smoking” (59.2%, 95% CI: 48.4–69.2%; and 68.4%, 95% CI: 59.2–76.4%, respectively). Among the three device brands, there were significant differences for several reasons for choosing a device brand, including price, time-to-heat, availability, used by friend, and endorsement in media (all p < 0.05).
3.4. Flavor Preference
Menthol (41.5%, 95% CI: 37.2–45.9%); tobacco (33.7%, 95% CI: 29.8–37.7%), and mentholated fruity (20.0%, 95% CI: 16.4–24.1%) were the most commonly preferred flavors among current HTP users. This flavor preference was also similar to exclusive HTP users (menthol: 47.5%, 95% CI: 38.5–56.7%; tobacco: 29.3%, 95% CI: 21.8–38.1%; and mentholated fruity: 20.3%, 95% CI: 13.8–28.9%). For HTP users who were current smokers, former smokers, and never smokers, the three most commonly preferred flavors were menthol (current smokers: 38.6%, 95% CI: 34.2–43.3%; former smokers: 49.2%, 95% CI: 38.4–60.2%; and never smokers: 65.0%, 95% CI: 28.2–89.7%), tobacco (current smokers: 35.7%, 95% CI: 31.5–40.2%; former smokers: 26.8%, 95% CI: 18.1–37.6%; and never smokers: 35.0%, 95% CI: 10.2–71.8%), and mentholated fruity (current smokers: 19.8%, 95% CI: 15.7–24.5%; and former smokers: 21.0%, 95% CI: 13.2–31.7%).
Among IQOS and glo users, the most commonly preferred flavors were menthol (IQOS: 52.6%, 95% CI: 47.0–58.2%; and glo: 51.8%, 95% CI: 41.0–62.4%), followed by tobacco (IQOS: 37.0%, 95% CI: 32.0–42.3%; and glo: 28.1%, 95% CI: 20.5–37.7%), and mentholated fruity (IQOS: 9.5%, 95% CI 5.9–15.0%; and glo: 19.0%, 95% CI: 12.4–28.0%). As there was no menthol flavor available for Ploom TECH, the most commonly preferred flavors were mentholated fruity (54.6%, 95% CI: 45.3–63.5), tobacco (29.2%, 95% CI: 21.9–37.8%), and coffee (15.0%, 95% CI: 9.5–22.9%).