Neurological effects
Nicotine is widely recognized as a psychoactive
substance126. Vapers experience craving, impaired
capacity to stop and withdrawal symptoms during abstinence (e.g.
irritability), which all suggest e-cigs potential of inducing nicotine
dependence127,128. Similarly to other substance use
disorders, adolescents are characteristically more vulnerable to
addiction129.
Despite ENDS representing a tobacco cessation strategy, the risk of
transition to conventional cigarettes in previously never smokers
represents an emerging issue of critical relevance, especially in young
people130–133. A recent meta-analysis showed that in
a population of teens and young adults who have never smoked, odds of
smoking initiation were 3 to 6 times higher in those who have ever used
e-cigarettes134. Evidence suggest also that higher
nicotine concentrations may heighten the likelihood of
progression135. In this perspective, the
renormalization of a smoking culture among teenagers threatens to
subvert decades of anti-smoking efforts.
Structural and neurochemical changes in the central nervous system lie
beneath the behavioral evolution that characterizes adolescence. Against
this background, nicotine can affect its regular course, contributing to
attention and cognitive deficits and exacerbating mood
disorders136.
Furthermore, in such a critical phase of human development, nicotine
exposure may prime the brain’s reward system increasing pleasing effects
of other substances of abuse137,138. As evidence of
this, youngsters smoking e-cigarettes display a greater risk of
co-occurring alcohol and/or marijuana use139.