Association between use of heated tobacco products and long-term health effects considering smoking history: Internet-based cross-sectional study in Japan

Abstract

Background With the use of heated tobacco products (HTPs) becoming more widespread in Japan, interested in the health effects of HTP use have grown. Since the vast majority of HTP users are former smokers, information about the user's smoking history and health status before HTP use is needed when assessing the health effects of HTP use. The limited epidemiological studies available did not consistently considered this information. Methods We conducted a cross-sectional study investigating the relationship between HTP use and respiratory chronic diseases and symptoms. A large-scale research panel in Japan managed by Cross Marketing Inc. was randomly sent questionnaires via the Internet, and individuals who met the study criteria and were either current exclusive HTP users, current exclusive cigarette users or those had never used tobacco products were selected. And obtained information about the participants' smoking history and health status before they used HTPs. The effects of participant smoking history prior to HTP use and the impacts on outcomes upon switching to HTP were assessed using a logistic regression model. And the odds ratio (OR) for current exclusive HTP users relative to never tobacco users was calculated. The OR was calculated under two scenarios, either ignoring or taking into account smoking history. Results Of the participants from whom responses to the questionnaires were obtained, 17,406 participants were included in the analysis. Almost all participating current exclusive HTP users had a history of long-term smoking (mean: 28.6 years), and the occurrence of outcomes both before and after the start of HTP use were reported. The ORs, without adjustment and with adjustment for smoking history prior to HTP use were, in the case of COPD, 3.23 (95% CI: 1.37–7.61) and 1.85 (95% CI: 0.70–4.89) respectively. These results suggest that smoking history prior to HTP using affects the occurrence of outcomes. Conclusions These results underscore the importance of considering smoking history when assessing the health effect of HTP use. Since the duration of HTP use is considerably shorter than that of cigarette use at present, further research, such as follow-up surveys assessing the long-term health effects of HTP use, will be necessary.