Change in E-cigarette risk perception and smoking behavior of Black and Latinx individuals who smoke.

INTRODUCTION:Trends in knowledge and beliefs about e-cigarette (EC) harm have been changing. Our study examined whether change in risk perception of ECs predicts cigarettes smoked per week (CPW) among Black and Latinx individuals who smoke enrolled in an EC switching randomized clinical trial (RCT). METHODS:We analyzed data from one arm of a 6-week EC RCT of individuals who smoke attempting to switch to nicotine salt pod system ECs (n = 110; Black, n = 57; Latinx, n = 53). Our explanatory variable was change in risk perception of ECs compared to combustible cigarettes (CC) from baseline to week 6. Our outcome was CPW measured by a 7-day timeline follow-back interview. A negative binomial GEE model was conducted to examine the association between risk perception and CPW at baseline and week 6. RESULTS:The mean CPW decreased from 82.8 (SD=49.8) at baseline to 15.8 (SD=29.8) at week 6. A one-level increase in EC risk perception (i.e., EC perceived as riskier than CC from baseline to week 6) was associated with an increase in CPW (IRR: 1.83, 95% CI: 1.03; 3.24). Latinx participants were more likely to have higher CPW as EC risk perception increased compared to Black participants (IRR=1.89, 95% CI: 1.09; 3.26). CONCLUSION:We found that CPW at week 6 was significantly higher as change in risk perception of EC relative to CC increased. Given the influence of risk perception on smoking behavior, people who smoke should be educated on the benefits and harms of ECs.