Dual use of combustible and heated tobacco products exacerbates long COVID prevalence: a JASTIS 2023 cross‑sectional study

Multiple reports have identified smoking as a risk factor for long COVID; however, few have distinguished among tobacco product types. We conducted a cross-sectional study using data from an internet-based survey administered in February 2023 to examine the association between 12 persistent symptoms and smoking status in participants with a history of COVID-19. A total of 28,250 participants were included, of whom 5,067 had a history of COVID-19. Among current tobacco users with a history of COVID-19, the odds ratios for persistent symptoms were significantly elevated for four symptoms—arthralgia, chest pain, dyspnea, and dysosmia—compared to never smokers. For subgroup analysis, current tobacco users were categorized into three groups: combustible cigarette (CC), heated tobacco product (HTP), and dual users. Among dual users, the odds ratios were significantly elevated for five symptoms: arthralgia, chest pain, dyspnea, dysgeusia, and dysosmia. CC users showed significantly higher odds for chest pain, dyspnea, and fatigue, while HTP users for dyspnea and sexual dysfunction. Smoking in individuals with a history of COVID-19 exacerbates the prevalence of persistent symptoms, and its impact may vary by smoking type. Separately analyzing smoking subgroups allows for a more accurate understanding of the relationship between long COVID and smoking behavior.