Is smoking reduction and cessation associated with increased e-cigarette use? Findings from a nationally representative sample of adult smokers in Australia.

E-cigarettes may benefit public health if they are effective for smoking cessation. Evidence suggests that the frequency of e-cigarette use is likely an important predictor of smoking cessation success, so we examined the associations between frequency of e-cigarette use and smoking reduction and cessation in an Australian population sample of past year adult smokers. Data from the 2019 National Drug Strategy Household Survey were used (N = 22,015). The sample was restricted to 3868 adults who had smoked within the past year. The outcome was self-reported smoking status and smoking reduction, adjusted for key potential confounders. Compared with no current e-cigarette use, daily e-cigarette users reported an increased likelihood for smoking reduction among current daily smokers (RRR = 2.83; 95% CI = 1.53, 5.22) and were more likely to report quitting smoking among past year smokers (RRR = 2.16; 95% CI = 1.30, 3.58). Smoking reduction and cessation for occasional e-cigarette use were not significantly different from no e-cigarette use. Daily, but not occasional, e-cigarette users were more likely to quit or reduce smoking cigarettes than Australian smokers who did not use e-cigarettes.