A national cohort study of the association between the polytrauma clinical triad and suicide-related behavior among US Veterans who served in Iraq and Afghanistan.

OBJECTIVES: We examined the association of posttraumatic stress disorder (PTSD), traumatic brain injury, and chronic pain-the polytrauma clinical triad (PCT)-independently and with other conditions, with suicide-related behavior (SRB) risk among Operation Enduring Freedom (OEF; Afghanistan) and Operation Iraqi Freedom (OIF) veterans.

METHODS: We used Department of Veterans Affairs (VA) administrative data to identify OEF and OIF veterans receiving VA care in fiscal years 2009-2011; we used International Classification of Diseases, Ninth Revision, Clinical Modification codes to characterize 211652 cohort members. Descriptive statistics were followed by multinomial logistic regression analyses predicting SRB.

RESULTS: Co-occurrence of PCT conditions was associated with significant increase in suicide ideation risk (odds ratio [OR] = 1.9; 95% confidence interval [CI]=1.5, 2.4) or attempt and ideation (OR=2.6; 95% CI=1.5, 4.6), but did not exceed increased risk with PTSD alone (ideation: OR=2.3; 95% CI=2.0, 2.6; attempt: OR=2.0; 95% CI=1.4, 2.9; ideation and attempt: OR=1.8; 95% CI=1.2, 2.8). Ideation risk was significantly elevated when PTSD was comorbid with depression (OR=4.2; 95% CI=3.6, 4.8) or substance abuse (OR=4.7; 95% CI = 3.9, 5.6).

CONCLUSIONS: Although PCT was a moderate SRB predictor, interactions among PCT conditions, particularly PTSD, and depression or substance abuse had larger risk increases.