The effect of smoking abstinence on risk of SRO is also unclear. A study of young adults followed for 10 years found that recent, but not presurvey, cigarette smoking predicted suicidal thoughts and attempts.14 Another study showed higher incidence rates of suicidal ideation among former smokers than never smokers, but the difference was no longer significant after adjustment with depressive disorder, anxiety symptoms and alcohol dependence.16 A study based on wave 1 data from the National Epidemiological Survey of Alcohol and Related Conditions (NESARC) initially found that longer duration of abstinence decreased risk for SRO, but this effect disappeared upon controlling for psychiatric comorbidity.21
