BACKGROUND: Despite being marketed as safer alternatives for conventional cigarette (CC) smokers, electronic cigarettes (EC) and heated tobacco products (HTP) face growing scepticism regarding their safety and effectiveness in promoting smoking cessation. Understanding the patterns of use of these products, and their associated health effects, is essential for public health.
METHODS: We analysed data from a sample of 22428 Italian adult participants who reported their use of CC, EC, and HTP and any adverse events - including dry cough, sore throat and dry mouth - specific to each product use. We used multivariate logistic regression models to assess the odds ratio (OR) of reporting adverse events in dual users versus CC-only smokers.
RESULTS: CC use was reported by 75.6% of EC users and 80.3% of HTP users. Product-specific adverse events were reported by 68.2% of CC smokers, 44.7% of EC users, and 44.5% of HTP users. Mean number of adverse events was 1.41 (standard deviation, SD=1.46) after CC smoking, 0.78 (SD=1.17) after EC use and 0.74 (SD=1.15) after HTP use. Compared to CC-only smokers, CC smokers also using EC (OR: 1.32, 95%-CI: 1.17-1.50), also using HTP (OR: 1.14, 95%-CI: 1.01-1.30), and also using both EC and HTP (OR: 1.50, 95%-CI: 1.29-1.75) had a higher risk of experiencing at least one adverse event after CC use.
CONCLUSIONS: Combining CC smoking with EC and/or HTP use increases the risk of adverse events after CC smoking. To this number must be added the far from negligible number of adverse events reported after EC and/or HTP use. Our findings reinforce the growing evidence of higher health risks for dual users compared to CC-only smokers, undermining the role of EC and HTP as effective tobacco control tools. This is particularly true in Italy, where almost all EC and HTP users are dual users.