Frequency of E-cigarette use and cigarette smoking among Canadian students.

The emergence of electronic nicotine delivery systems (commonly referred to as e-cigarettes) has created an ongoing public health debate and concerns, especially in regards to adolescents. The present study examined associations between the frequency of e-cigarette use and cigarette smoking among school students. Data on students (grades 7-12) was obtained from the 2016-2017 Canadian Student Tobacco, Alcohol and Drugs Survey (n = 51,661). Multivariable logistic regression analyses were conducted to examine associations between the frequency of e-cigarette use and smoking. Subgroup analyses were performed for male and female students. Among those who reported any cigarette smoking in the past 30 days, 55% reported e-cigarette use at least once in the last 30 days. Additionally, 17% reported e-cigarette use for 21-30 days among those who smoked cigarettes for at least 21 days. Multivariable logistic regression analysis showed e-cigarette use was associated with higher odds of cigarette smoking, especially among more frequent e-cigarette users. Those who used an e-cigarette 21-30 days had higher odds of cigarette smoking (smoked cigarette at least once AOR = 4.83, CI = 3.33-7.01; at least 11 days AOR = 3.73, CI = 2.40-5.80; at least 21 days AOR = 3.39, CI = 2.16-5.34). Findings suggest that those who smoked cigarettes at least once in the past 30 days had a higher frequency of e-cigarette use.