Heated tobacco product use and abnormal glucose metabolism: a working population-based study

Aims We aimed to assess the cross-sectional association of heated tobacco product (HTP) use with prediabetes and diabetes.Methods The present analysis included 8950 workers from 5 companies (Study I) and 31,341 workers from another large company (Study II), who participated in the Japan Epidemiology Collaboration on Occupational Health Study. The participants were divided into five groups: never smokers, past smokers, exclusive HTP users, dual users of cigarettes and HTPs, and exclusive cigarette smokers. Diabetes and prediabetes were defined according to the fasting blood glucose and HbA1c levels and self-reported diabetes treatment, using the American Diabetes Association criteria. We analyzed the data of Study I and II separately, and then pooled these estimates using the fixed-effect models, with adjustment for a wide range of covariates.Results In this study that included 40,291 participants (mean age, 46.6 years; men, 84.3%), about half of the current tobacco related product users reported using HTPs. Exclusive HTP users had higher odds of prediabetes (pooled odds ratio 1.36; 95% CI 1.25-1.47) and diabetes (1.68; 95% CI 1.45-1.94) than never smokers. Similarly, dual users also had increased odds of prediabetes (pooled odds ratio, 1.26; 95% CI 1.13-1.39) and diabetes (1.93; 95% CI 1.63-2.29). The strength of these associations was comparable to that of cigarette smokers. We observed significantly higher HbA1c and fasting blood glucose levels among both exclusive HTP users and dual users compared to never smokers.Conclusion HTP use was associated with an increased likelihood of prediabetes and diabetes. Prospective studies are warranted to confirm the cross-sectional association.