Prospective Associations of Depression and Anxiety Symptoms with the Transition from Suicidal Ideation to Attempt over 18 Months

BACKGROUND:Anxiety and depressive disorders are known risk factors for suicide. However, limited prospective research has tested whether mental disorders are associated with transitions from suicidal ideation (SI) to suicide attempt (SA). Our primary aim was to test the effects of mental disorder symptoms on SA over 18 months. METHOD:Symptoms of major depression, generalized anxiety, social anxiety, obsessive-compulsive, and post-traumatic stress disorders, and psychological distress were assessed in a population-based sample of 923 Australian adults with SI (mean age 36.2 years, 65.2% women). SI severity and time to SA were then assessed every 6-months for 18-months, with 86% retention. All measures were self-reported. RESULTS:Suicide attempts were reported by 106 participants (11.5%) during the follow up period. Baseline depressive and post-traumatic stress symptoms were associated with increased hazard of SA at 18-months (HR = 1.064, 95%CI: 1.001-1.131 and HR = 1.264, 95%CI: 1.046-1.526 respectively), while baseline obsessive-compulsive symptoms had a small negative association with SA (HR = 0.960, 95%CI: 0.925-0.996). Greater depression or distress symptoms at baseline were associated with more severe SI at 18-months. Sensitivity analyses indicated that lifetime suicide attempt history attenuated symptom-level associations, such that only baseline PTSD associations remained significant for SA. CONCLUSION:Depression and anxiety disorder symptoms were significantly associated with subsequent SI and SA over 18 months, although effects on SA were modest and attenuated by lifetime SA. Findings support potential moderation of mental health effects based on lifetime suicide attempts, and suggest that further examination of the role of suicide capability within specific mental disorders is needed.