Prospective prediction of first lifetime onset of suicidal ideation in a national study of substance users.

Suicide rates have increased over the past several decades. Prior research has evaluated risk factors for suicidal behavior, but much of this work does not adequately differentiate between risk factors for suicidal ideation (SI) and suicide attempts, nor does it differentiate between first-onset SI and recurrent ideation. This study seeks to identify risk factors for first-onset SI among a high-risk group: individuals receiving treatment for substance use disorders. Data were drawn from the National Treatment Improvement Evaluation Study, a prospective study examining the impact of addiction treatment programs. Patients with no lifetime history of suicide attempts or ideation (n = 2560) were assessed at baseline and one year later for prospectively-occurring SI. Sociodemographic variables, mental health indices, interpersonal factors, and substance use severity indicators were evaluated as prospective predictors of first-onset SI in linear regression models. Current mental health problems (OR = 1.54, 95% CI = 1.19-2.01), current substance use problems (OR = 1.33, 95% CI = 1.04-1.70), and difficulty accessing treatment for substance use problems (OR = 1.90, 95% CI = 1.16-3.11) emerged as significant predictors of first-onset SI in a multivariate analysis, suggesting that individuals with current mental health or substance use related symptoms are among the most at risk for developing SI. Difficulty obtaining treatment remained significant, highlighting the importance of treatment accessibility. Future clinical work and research would benefit by addressing these issues, potentially by focusing on mental health treatment in substance abuse programs and evaluating barriers to treatment.