Single versus recurrent depression history: differentiating risk factors among current US smokers

The strong relationship between persistent tobacco use and Major Depressive Disorder (MDD) has motivated clinical trials of specialized treatments targeting smokers with a history of MDD. Meta-analyses suggest positive responses to specialized treatments have been observed consistently among smokers with history of recurrent rather than a single episode of MDD. Approximately 15% of current US smokers have a history of recurrent MDD. Little is known about the risk factors that contribute to persistent smoking and differentiate these at-risk smokers, US.

The National Comorbidity Survey - Replication (NCS-R) included a survey of 1560 smokers participants aged 18 and older in the United States. Lifetime history of MDD was categorized according to chronicity: no history (No MDD), single episode (MDD-S) and recurrent depression (MDD-R). The relationship between the chronicity of MDD, smoking characteristics, cessation history, nicotine dependence, comorbidity with psychiatric disorders, and current functional impairments were examined.

MDD-R smokers reported fewer lifetime cessation efforts, smoked more cigarettes, had higher levels of nicotine dependence, had higher rates of comorbid psychiatric disorders and greater functional impairment than smokers with No MDD. MDD-S smokers were not consistently distinguished from No MDD smokers on cessation attempts, level of daily smoking, nicotine dependence or functional impairment indices.

The study highlights the importance of chronicity when characterizing depression-related risk of persistent smoking behavior. Although, clinical trials suggest MDD-R smokers specifically benefit from specialized behavioral treatments, these services are not widely available and more efforts are needed to engage MDD-R smokers in efficacious treatments.