Connecting the Dots: From E-Cigarettes to Tobacco Smoking

Vaping has been shown to predict future smoking in adolescents, but the details of this connection have not been well described. Researchers analyzed survey data from 181 tenth-grade students from greater Los Angeles who reported vaping in the 30 days prior to the survey. Students estimated the usual nicotine concentration in their e-cigarettes to be none, low (1–5 mg/mL), medium (6–17 mg/mL), or high (≥18 mg/mL). At 6-month follow-up, they were surveyed on their frequency and intensity of smoking and vaping. Frequency was defined by number of days smoking or vaping in the last 30, grouped into none (0 days), infrequent (1–2 days), and frequent (≥3 days). Intensity was measured as number of cigarettes or vaping episodes per day and number of puffs per vaping episode.

At 6 months, for each step up in self-reported nicotine concentration, the students were 2.26 times more likely to be frequent (vs. non-) smokers and 1.65 times more likely to be frequent (vs. non-) vapers after adjustment for baseline smoking and vaping, as well as demographic, intrapersonal, and interpersonal covariates. High nicotine concentration (vs. none) was associated with more cigarettes smoked per day, and any nicotine level beyond none was associated with more vaping episodes per day and more puffs per episode.