Compared with US adults who have never used electronic cigarettes (e-cigarettes), those who have used e-cigarettes had higher odds of reporting a history of a clinical diagnosis of depression, according to a cross-sectional study of nearly 900,000 people published in JAMA Network Open.
“At the very least, our findings warrant careful and thorough evaluation of e-cigarette use in both youth and adults with depression,” researchers wrote. “Physicians should consider routine collection of information pertaining to e-cigarette use during clinic visits, especially in patients with depression, and routine counseling for those who use e-cigarettes, offering support to those who express willingness to quit.”
The study included 892,394 participants in the Behavioral Risk Factor Surveillance System database, the largest telephone-based survey of randomly sampled US adults, from 2016 to 2017. Current users of e-cigarettes, the survey found, were more likely to be single, male, younger than age 40, and current combustible cigarette smokers.
Respondents who said they were former e-cigarette users had 1.60-fold higher odds of reporting a history of clinical diagnosis of depression, and current e-cigarette users had 2.10-fold higher odds, compared with respondents who had never used e-cigarettes, according to the study. In addition, the odds of reporting depression among current users grew with increased frequency of e-cigarette use.
“Prolonged nicotine exposure has been shown to disrupt the cerebral dopamine pathway, amplify stress sensitivity, and distort the coping mechanisms that buffer against depressive symptoms,” researchers wrote. “As many e-cigarettes contain nicotine, this could explain the graded association seen with increased frequency of use and depression, suggesting a potential dose-response relationship.”
Pointing out that smoking traditional cigarettes can affect the metabolism, and consequently effectiveness, of various psychiatric medications, researchers expressed concern e-cigarette use could complicate the treatment of people with psychiatric conditions.
“Our findings, if confirmed in other study designs with longitudinal follow-up, may provide data to inform policies that could protect populations susceptible to depression,” researchers wrote.
“For example, the association between e-cigarette use and depression might justify further regulation of advertisements and marketing strategies, appropriate warning labels that highlight the potential risk of depression associated with e-cigarette use, and public health education about the potential effects of e-cigarettes, especially among those with mental health conditions.”