Increased Risk of Major Depression With Early Age of Exposure to Cigarettes.

INTRODUCTION: This study examined the association between age of initiation of cigarette use and increased risk of lifetime major depressive episode.

METHODS: This study utilized publicly available data from the 2013 National Survey on Drug Use and Health involving a nationally representative sample of interviews of 55,160 randomly selected people aged ≥12 years. Analysis was conducted in 2016. Age of initiation of cigarette use was divided into four groups (≤12 years, 13-14 years, 15-18 years, and >18 years). Eligible participants included adults aged ≥18 years who had ever smoked a cigarette and had non-missing data for all analytic variables (n=23,906). Associations between lifetime major depressive episode and covariates were assessed using chi-square tests. Logistic regression was used to calculate crude ORs and AORs with 95% CIs.

RESULTS: About half of participants reported starting cigarette use when they were aged 15-18 years. Compared with the group that initiated cigarette use at age ≤12 years, all other age groups were from 25% to almost 50% less likely to report a lifetime major depressive episode.

CONCLUSIONS: Early age of onset of cigarette use is associated with increased likelihood of experiencing a lifetime major depressive episode. Further research is needed to elucidate the mechanisms driving this association.