Abstract 4361034: Spread of heated tobacco products and hospitalizations of acute coronary syndrome

Background: Heated tobacco products (HTPs) have gained traction as alternatives to conventional cigarettes. Its use is rapidly gaining popularity among young adults since 2017, especially in Japan, with a current prevalence of more than 50% of the smokers. Despite uncertainties regarding the adverse health effects of HTPs, concerns regarding nicotine and potentially harmful constituents persist. However, little is known whether HTP use is effective for reduction of the cardiovascular diseases incidence such as acute coronary syndrome (ACS). Methods: Using JROAD-DPC dataset from April 2013 to March 2022, a longitudinal trend of the number of ACS hospitalizations all over Japan as well as in local areas was examined. Interrupted time-series analysis was performed before and after the introduction of HTPs to interrupt its trend. The slope and 95% confidence interval (CI) were calculated with seasonal adjustment. Results: The hospitalizations of total 370,178 patients with ACS in 300 hospitals were analyzed. In total population, no significant changes in ACS hospitalizations were observed between before and after the introduction of HTPs (slope difference [95%CI]: -3.66 [-9.67, 2.35]). However, when limited to younger patients, among whom the proportion of HTP use is increasing up to 50 %, the trend started to decrease after introduction of HTP (-1.23 [-1.80, -6.50]). In smoking subjects, the similar change was observed. The changes were also significant at Tokyo area and areas with higher HTP prevalence (-2.47 [-3.44, -1.49]) and -3.66 [-5.98, -1.35], respectively). In contrast, there were no such changes among older people (aged 50 years and older), non-smokers, and 10 prefectures with lower prevalence of HTP use. Conclusions: Following the nationwide spread of HTP in Japan, a decreasing trend in ACS hospitalizations was observed among younger, smoking population, and in regions with higher HTP prevalence.