New tobacco products and smoking prevalence in Italy: a double-intervention time series analysis

Abstract Background Tobacco smoke is a major risk factor to noncommunicable disease (NCD) and its role is under study in the Joint Action PreventNCD. This study assessed the impact of new tobacco and nicotine products, i.e., electronic cigarettes (e-cig) and heated tobacco products (HTP), on smoking prevalence in the adult population residing in Italy. Methods Istituto Superiore di Sanità (ISS) uses behavioral surveillance systems for monitoring purpose in PreventNCD. PASSI surveillance system data 2008-2023 amount 532,115 interviews on adults (aged 18-69) residing in Italy. From the weighted monthly series on smokers’ prevalence, interrupted time series (ITS) were analysed, with generalized least squares, accounting for autocorrelation (ARMA matrix). January 2024 (introduction of e-cig in data collection) was used as “first-interruption” month, and January 2018 (introduction of HTP) as “second-interruption” month. The analysis shows the difference between what occurred after the intervention and expected outcome in the hypothesis of no intervention. The exclusive or combined use of the three products was also evaluated. Results Cigarettes smokers trend decreased from 30% to 24%, but the ITS analysis shows how the introduction of new tobacco and nicotine products and consuming shift, mostly combined, interrupted the declining trend in cigarettes use in Italy. There is no reduction in the total amount of nicotine addict or tobacco users: since PASSI started investigating new electronic devices, we observe a constant decrease in the number of exclusive traditional cigarettes users (from 25% in 2014 to 20% in 2023), in favor of an increase in both traditional cigarettes and electronic devices (from 1.5% in 2014 to 4.4% in 2023) users. Exclusive electronic devices users also slowly increased, from 0.4% in 2014 to 3.3% in 2023. Conclusions Exclusive use of cigarettes decreased as combined use with e-cig increased; exclusive use of electronic devices slowly increased. Key messages • Combined use of traditional cigarettes and electronic devices represents a challenge for public health, as it increases health risks caused by exposure to higher nicotine and harmful chemicals levels. • Tobacco and nicotine users did not decrease with the introduction of new electronic devices.