https://orcid.org/0000-0003-1444-3761
Figures
Abstract
The aim of this study is to analyze the differences between telemedicine and face-to-face examinations for smoking cessation in terms of long-term abstinence and completion rates in a large Japanese population. Although the effectiveness of various smoking cessation methods has been confirmed, the treatment outcomes of face-to-face interviews for tobacco cessation are still insufficient, because it is bother to go to a clinic regularly for most patients. In line with current trends of developing digital healthcare services, we assessed the role of telemedicine as a potential tool in smoking cessation clinics. A total of 5005 current smokers who applied for the telemedicine smoking cessation program between April 2021 and December 2022 and a total of 1308 current smokers who visited some smoking cessation clinics between April 2016 and March 2017 were included. Clinical data, such as age, sex, Brinkman index, were collected from all the participants, in addition to a preliminary questionnaire including smoking habits, reason for applying and self-efficacy for smoking cessation. This online program consists of four sessions in the first 8 weeks, with a 1-year follow-up period (final follow-up at 52 weeks). The success rates of long-term smoking abstinence at week 52 and the completion rates of scheduled treatment with varenicline or nicotine patches were compared between the telemedicine and face-to-face examinations. Data on face-to-face examinations were obtained from the database of the Ministry of Health, Labor and Welfare in Japan for comparison. A total of 3708 patients (3364 men and 352 women) were analyzed. The completion rate of this program (68.2%) was significantly greater than that of face-to-face examinations (29.8%). The long-term abstinence rate was significantly greater with telemedicine than with conventional examination (P < 0.005). In conclusion, the findings revealed that telemedicine is helpful for long-term abstinence from smoking on the basis of improved availability and accessibility.
Citation: Takakura K, Ishizawa T, Aoki Y, Matsumoto K, Tanaka TD, Koyama M, et al. (2026) Enhancing the long-term abstinence rate of smoking through telemedicine: A multicenter, retrospective cohort study in Japan. PLoS One 21(7): e0331514. https://doi.org/10.1371/journal.pone.0331514
Editor: Mukhtiar Baig, King Abdulaziz University Faculty of Medicine, SAUDI ARABIA
Received: April 23, 2025; Accepted: July 6, 2026; Published: July 22, 2026
Copyright: © 2026 Takakura et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All relevant data are within the manuscript and its Data Availability Statement files.
Funding: The author(s) received no specific funding for this work.
Competing interests: The authors have declared that no competing interests exist.
Introduction
Although the prevalence of tobacco consumption has been gradually decreasing worldwide, the Japanese smoking rate was still 20.1% in 2020, which was almost the same as the earlier rate [1]. Besides, the economic and social disparity in smoking has been expanding in Japan, similar to other developed countries, especially among the working generation [2]. In addition, the success rate of continuous smoking cessation is unsatisfactory because of the limited treatment persistence rate with conventional, face-to-face examination for smoking cessation [3,4]. In current situation of overcrowded medical facilities in Japan, patients have to wait for a long time to be seen by the doctor. It makes patients feel difficulty in receiving the medication for quitting smoking. However, a wide variety of evidence demonstrating the physical, mental, financial and social benefits of smoking cessation have been accumulating [5–15]. Considering not only the various health impairments stemming from smoking, but also the fact that tobacco is the primary cause of death in Japan [16], further promotion of smoking cessation and drastic measures for remedying smoking-related health inequalities at a younger age are urgently needed.
During the COVID-19 pandemic, the availability and accessibility of telemedicine, a digital health service, was promoted in various healthcare fields, including tobacco cessation clinics [17–19]. Indeed, several studies have reported the usefulness of telemedicine for smoking cessation, though limited number of patients or limited follow-up duration [20,21]. Since a previous study that used the same fully online smoking cessation program mainly focused on comparison of therapeutic outcomes between conventional cigarettes and heated tobacco products (HTPs) through telemedicine [22], we focused on comparing smoking cessation outcomes with telemedicine versus face-to-face examinations from a different perspective. Nicotine-dependent patients are commonly eligible for a 12-week standard smoking cessation treatment program with 5 clinic visits and an initial screening interview in which their exhaled carbon monoxide levels are checked in Japan [23]. Therefore, the duration of this smoking cessation program with varenicline was 8 weeks in a relatively short span of time, whereas that of the conventional program is 12 weeks with varenicline.
Given the insufficient clinical evidence regarding the usefulness of telemedicine for smoking cessation, we evaluated long-term smoking abstinence rates at 52 weeks from starting the program, as well as the completion rate of the scheduled treatment for 8 weeks in comparison with face-to-face examinations in this multicenter study involving thousands of participants.
Materials and methods
Study design and population
A total of 5005 current smokers aged 20 years or older who applied for the telemedicine smoking cessation program through the health insurance association between 01/04/2021 and 31/12/2022 were potentially eligible for inclusion in this retrospective cohort study. Following enrollment into the cohort, the participants’ clinical information were accessed on 01/06/2024. A total of 20 Japanese medical institutes were entered, and the number of patients enrolled were at minimum 3, and maximum 1265. Most patients were participated not as an individual but from each business site. In a preliminary questionnaire, participants were asked about their duration of smoking, previous smoking cessation history, number of cigarettes per day, reason for applying to the program past medical history and self-efficacy for quitting smoking. Clinical data, such as age, sex, body mass index (BMI), Brinkman index, the Tobacco Dependence Screener (TDS) score [24] and treatment methods were collected at baseline and in follow-up surveys. In addition, the individual’s occupation, type of cigarette, drinking habits and complications of depressive symptoms identified by Whooley Questions for depression screening were also similarly recorded [25]. The degree of self-efficacy for quitting smoking was assessed by dividing the participants into 3 groups: low (0−24%), medium (25−74%) and high (75−100%). For the evaluation of therapeutic efficacy, 1297 censored patients were finally excluded from the analyses, as shown in Fig 1. A summary of the data collected from the study patients is presented in Table 1. The study protocol was approved by the ethics committee of UnMed Clinic Motomachi, Kanagawa, Japan (authorization number: UM24−01). The review board approved and waived the need for written informed consent from the participants because of the retrospective, noninterventional nature of this study. The study followed the recommended guidelines of the Declaration of Helsinki.
Reasons for screening failure and discontinuation from the study are indicated.
The telemedicine smoking cessation program
The smoking cessation program, provided online by Linkage, Tokyo, Japan, was implemented at all the clinics that participated in this study (Fig 2) [22]. This fully remote online program consists of four sessions in the first 8 weeks, with a total follow-up period of 1 year via surveys and support via an app at weeks 12, 24, 36 and 52. In the telemedicine sessions, the doctors assessed the participants’ progress in tobacco cessation and provided practical advice on quitting smoking each time. Varenicline or nicotine patches were selectively prescribed as anti-smoking drugs on the basis of the patient’s condition. The participants could receive varenicline or nicotine patches directly at home for a total duration of 8 weeks without the need for clinic visits. Moreover, qualified experts of smoking cessation provided constant supports for the patients via email within the follow-up period.
Conventional smoking cessation program
Conventional program consists of five face-to-face examinations in the first 12 weeks, with a total follow-up period of 52 weeks. The patients selectively received varenicline for a total duration of 12 weeks or nicotine patches for a total duration of 8 weeks at each medical institutes. Data on conventional therapy were obtained from the most recent database of the Ministry of Health, Labor and Welfare (MHLW) in Japan for comparison of this study. A total of 1308 current smokers who visited some smoking cessation clinics between April 2016 and March 2017 were included in the database reported in 2017 [23]. A total treatment duration with varenicline (12 weeks) is 4 weeks longer than that with the telemedicine program (8 weeks), although a total treatment duration with nicotine patches (8 weeks) and total follow-up period of 52 weeks are the same.
Outcomes
The primary outcome was the long-term smoking abstinence rate at week 52 after 8 weeks of treatment with varenicline or nicotine patches following treatment through telemedicine or face-to-face interviews and its related factors.
The secondary outcome was completion rates of the scheduled treatment in the context of telemedicine versus face-to-face interviews and its related factors. Additionally, we compared the therapeutic efficacy of varenicline versus nicotine patches, a form of nicotine replacement therapy (NRT), administered through the online program.
Statistical analysis
All the statistical analyses were performed using SAS V.9.4 software (SAS Institute, Cary, NC, USA). The percentages of patients who completed the scheduled treatment with varenicline and nicotine patches were compared using the χ-square test. Completion rates were compared with those reported by the MHLW using the one-sample Z-test. Multiple logistic regression analysis was performed to identify factors associated with treatment completion. Odds ratios (ORs) and 95% confidence intervals (CIs) for treatment completion were calculated using multivariate adjustment. Independent variables to be input into the model were confirmed that there is no strong correlation among them (r > 0.80). The result of Hosmer-Lemeshow goodness-of-fit test was good (p = 0.898). The significance level was set at p < 0.05.
Results
Participant characteristics
A total of 3708 patients who participated in the smoking cessation program at several medical institutes between April 2021 and December 2022 were included in the analyses (Fig 1). The baseline characteristics of the study participants are summarized in Table 1. The median age of the enrolled patients was 43.6 ± 10.5 years, with 3364 (90.5%) men and 352 (9.5%) women. Among them, 65.5% were underweight or of normal weight (BMI < 25 kg/m2), and 34.4% were overweight (BMI ≥ 25 kg/m2). The types of smoking products included combustible cigarettes in 40.4%, and HTP in 42.7%, while 16.9% were dual users. Although the number of cigarettes smoked was < 20 per day in 88.1% of the participants, the duration of smoking ranged from 1–20 years in 41.5%, 21–40 years in 51.6% and more than 40 years in 6.9%. Alcohol was consumed by 1694 participants (45.6%), and 987 (26.6%) had mental illnesses. In terms of occupation, blue- and white-collar workers numbered 1507 (40.6%) and 2201 (59.4%), respectively. According to the preliminary questionnaire, the degree of self-efficacy at the initiation of treatment was low in 21.5%, medium in 62.6% and high in 15.9% of the study participants.
A total of 1308 current smokers who visited some smoking cessation clinics between April 2016 and March 2017 were included for comparison. The most common age of the enrolled patients was 40–49 years, with 873 (66.7%) men, 400 (30.6%) women and 35 (2.7%) non-respondent patients.
High completion rate of scheduled treatment through telemedicine
The completion rate of scheduled treatment in the fully online program (68.2%) was significantly higher than that of face-to-face examinations (34.6%) reported by the MHLW. This was possibly due to the easy accessibility of telemedicine without the need for clinic visits and the availability of direct home-delivery of the drugs. Moreover, varenicline (78.8%) showed significantly higher completion rates than nicotine patches (65.4%) in the online program, similar to conventional treatment (P < 0.001) (Table 2).
Factors related to the completion rate according to logistic regression analysis
As shown in Table 3, older age (OR 1.99; 95% CI 1.40–2.82), HTP user (OR 1.37; 95% CI 1.02–1.84), a higher Brinkmann index (OR 1.07; 95% CI 1.00–1.15) and higher self-efficacy (OR 1.08; 95% CI 1.03–1.14) were significant factors in the completion rate of the scheduled treatment according to logistic regression analysis. Conversely, sex, BMI, alcohol habits, occupation, mental disorders, TDS score and non-smoker status were not significantly correlated with the completion rate of the scheduled treatment.
Telemedicine enhanced long-term smoking cessation rates
A total of 3698 patients were included in the comparative analysis of the results of the 1-year follow-up. Four hundred thirty-three of 805 varenicline users (53.8%) and 1230 out of 2893 nicotine patch users (42.5%) were able to quit smoking continuously, even though only 28.3% of the varenicline users and 34.5% of the nicotine patch users were in the same setting reported from the MHLW in Japan (Table 4). Taken together, the long-term abstinence rate was significantly greater with telemedicine rather with conventional examination regardless of the therapeutic method used (P < 0.001).
Factors related to the abstinence rate according to logistic regression analysis
Next, we assessed factors related to the abstinence rate at the 1-year follow-up from therapeutic initiation. As shown in Table 5, older age (OR 1.60; 95% CI 1.34–1.91), blue-collar workers (OR 0.85; 95% CI 0.74–0.98), depressive symptoms (OR 0.82; 95% CI 0.71–0.96), HTP users (OR 1.34; 95% CI 1.15–1.56) and higher self-efficacy (OR 1.05; 95% CI 1.02–1.08) were significantly related to outcomes. In addition, participants who used varenicline had a higher abstinence rate than those who received nicotine patches in the online program (OR 0.66; 95% CI 0.57–0.78). On the other hand, sex, BMI, alcohol habit, Brinkman index, TDs score and non-smoking status were not correlated with the long-term abstinence rate.
Discussion
This multicenter, retrospective cohort study revealed significant difference in long-term smoking abstinence rates between the group treated through telemedicine and the group treated through face-to-face interviews at 52 weeks from treatment initiation. The improvement in the abstinence rates observed in the present study highlights the better completion rate of the scheduled treatment with the online program, likely since it is a more convenient therapeutic method and contributes to enhance self-efficacy for quitting smoking. Telemedicine allows smokers to undergo medical consultations and to receive prescriptions without the need for clinic visits, whereas a total of 5 times follow-up visits is needed in face-to-face examinations. Moreover, it is conceivable that the constant supports from our experts of smoking cessation within the 1-year follow-up also contributed for this online program. A previous report from Japan, which also compared the results of telemedicine versus conventional examinations, evaluated short-term abstinence rates for smoking cessation [26]. Another study from the United States assessed telemedicine versus telephone counseling for smoking abstinence at month 12 [20]. In addition, a report from Turkey showed the utility of telemedicine in comparison to traditional counseling by evaluating smoking cessation status at 6–9 months of follow-up [21]. To the best of our knowledge, this is the first large-scale study to compare the long-term smoking abstinence rates achieved by telemedicine versus face-to-face examination. Since the risk of smoking relapse is particularly high within the first year after cessation, we followed the patients for 1 year after treatment initiation in this study and evaluated the therapeutic outcomes at that time [27]. Thus, our results help elucidate the potential role of telemedicine in smoking cessation.
In this study, it is noteworthy that self-efficacy was a significant factor not only for the completion rate, but also for the abstinence rate. The results suggest that a telemedicine-supported program has a greater impact on improving self-efficacy for tobacco cessation, leading to better outcomes. The fact that self-efficacy is closely related to supporting smoking cessation is already well known [28–32]. Our data are consistent with previous studies and suggest that self-efficacy in quitting smoking can be positively influenced by the availability of treatment.
Interestingly, occupation, whether the participant was a blue-collar or white-collar worker, was a significant factor in the long-term abstinence rate, although there was no correlation with age. As previously reported, responding to socioeconomic inequalities in relation to smoking cessation still remains a task for the future [2,33]. Additionally, since several studies have indicated that younger smokers are more likely to be able to quit smoking successfully than older smokers are, further investigations into age-related factors for successful smoking cessation are needed [34,35].
In the comparison of varenicline and NRT in the online program, varenicline yielded better results than nicotine patch in terms of both the completion rate and the long-term abstinence rate, similar to the results for face-to-face examinations [36,37]. Although, varenicline is currently not readily available in Japan, the resumption of varenicline sales is expected very quickly [38].
This study has some limitations. First, the participants in this program were all members of the Japanese health insurance association, i.e., they were all within the working generation. Hence, it is likely that there is some selection bias in this study. Second, a total treatment duration with varenicline through this online program was 8 weeks, even though varenicline is usually prescribed for 12 weeks at conventional, face-to-face clinics [39–41]. For a valid comparison, these two programs should be similar to ensure that any differences are due to the delivery format rather than other factors. Thus, we compared the study data with pre-existing data reported from the MHLW by setting the same follow-up period of 52 weeks from treatment initiation, to unify the total follow-up period. Third, continuous abstinence rates were assessed by questionnaire-based self-reported abstinence, but not biochemically validated, which could misclassify smoking status or overestimate abstinence rates. Fourth, we excluded participants unavailable for follow-up surveys in the 52 weeks, which could potentially affect the completion and success rates of the telemedicine smoking cessation program. Finally, our data suggests differences in certain trends between white-collar worker and blue-collar worker. Thus, participant demographics, such as white-collar worker and blue-collar worker, may have an impact on the results of smoking cessation according to the differences in resources including working environment.
A key strength of our study was the large number of participants included from multiple medical institutions with complete follow-up for 52 weeks. Our study provides definitive insights into continuous smoking abstinence and the potential efficacy of telemedicine in smoking cessation.
In conclusion, telemedicine is definitely helpful for long-term abstinence from smoking, on the basis of its improved availability and accessibility. The higher completion rate of the scheduled treatment was likely a key player in the observed therapeutic outcomes. In addition, the resumption of varenicline sales is desirable, in view of its better outcomes than NRT in telemedicine, which is similar to conventional examinations.
Acknowledgments
We would like to express our sincere gratitude to Ryosuke Onishi of Linkage, Inc, Tokyo, Japan for his cooperation in this study. The authors thank FORTE Science Communications (https://www.forte-science.co.jp/) for English language editing.
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