Duration of smoking abstinence and suicide-related outcomes

To investigate the association between suicide-related outcomes (SROs: wish to die, suicidal thoughts, and attempted suicide) and duration of smoking abstinence.

The National Epidemiologic Survey on Alcohol and Related Conditions Wave 1 is a face-to-face survey of a representative sample of the U.S. adult population (N = 43,093). Analyses were done for a subsample of individuals (N = 13,691) who reported ever smoking, at least 2 weeks of lifetime depressed mood and SROs. Duration of abstinence was categorized as 1-24 hr (reference), 1 day to 12 months, and longer than 12 months.

Univariate analyses showed significant demographic associations (positive: female gender and being widowed/divorced/separated; negative: age and household income) with SROs. SROs were positively associated with major psychiatric disorders (dysthymia, major depression, generalized anxiety disorders, antisocial personality disorder, nicotine dependence, and alcohol abuse/dependence). Logistic regression showed that nonsmoking for more than a year compared with less than 24 hr (nonabstinence) was significantly associated with reduced risk for wish to die (odds ratio [OR]: 0.56, 95% CI: 0.49-0.65), suicidal thoughts (OR: 0.54, 95% CI: 0.48-0.62), and attempted suicide (OR: 0.32, 95 % CI: 0.26-0.41). With adjustments for lifetime psychiatric disorders, duration of abstinence was no longer significantly associated with the SROs.

In the sample of ever-smokers with lifetime depressed mood, an apparent protective effect of increased duration of smoking abstinence on susceptibility to suicidal behavior was neutralized by the presence of psychiatric disorders. The causal direction of these relationships is unclear, and these cross-sectional findings need confirmation in future prospective studies.