Many studies have consistently found an association of current smoking and risk of suicidal thoughts or behaviors (see Section 3.2.2. below). Current smoking could be associated with suicide due to “third factors” or “confounders” that are correlated both with smoking and suicide (Hemmingsson & Kriebel 2003; Kessler et al. 2007; Smith et al. 1999). This is plausible because many of the risk factors for suicide (Sudak 1999) are also risk factors for being a smoker; e.g., younger age, non-White, lower income, less education, unmarried, unemployed, less religious, anxiety, depression, psychoses, substance use problems, low self-esteem, risk taking, having a serious physical illness, impulsivity, aggression, antisocial personality, fatalism, emotional instability, etc. (US Department of Health and Human Services 1994). In addition, certain genes appear to predispose to both smoking and depression (Kendler et al. 1993).
