Contributions of posttraumatic stress disorder (PTSD) and mild TBI (mTBI) history to suicidality in the INTRuST consortium

ABSTRACT

Objective

Mild TBI (mTBI) and posttraumatic stress disorder (PTSD) are independent risk factors for suicidal behaviour (SB). Further, co-occurring mTBI and PTSD increase one’s risk for negative health and psychiatric outcomes. However, little research has examined the role of comorbid mTBI and PTSD on suicide risk.

Methods

The present study utilized data from the Injury and TRaUmatic STress (INTRuST) Consortium to examine the prevalence of suicidal ideation (SI) and behaviours among four groups: 1) comorbid mTBI+PTSD, 2) PTSD only, 3) mTBI only, and 4) healthy controls.

Results

Prevalence of lifetime SI, current SI, and lifetime SB for individuals with mTBI+PTSD was 40%, 25%, and 19%, respectively. Prevalence of lifetime SI, current SI, and lifetime SB for individuals with PTSD only was 29%, 11%, and 11%, respectively. Prevalence of lifetime SI, current SI, and lifetime SB for individuals with mTBI only was 14%, 1%, and 2%, respectively. Group comparisons showed that individuals with mTBI alone experienced elevated rates of lifetime SI compared to healthy controls. History of mTBI did not add significantly to risk for suicidal ideation and behaviour beyond what is accounted for by PTSD.

Conclusion

Findings suggest that PTSD seems to be driving risk for suicidal behaviour.

KEYWORDS:

• Mild brain injury
• posttraumatic stress disorder
• suicide risk

Acknowledgments

Data were collected for this study under a grant from the US. Army Medical Research and Material Command (USAMRMC), USAMRMC. Funding Mechanism: Contract #W81XWH-08-2-0159 (Stein et al.), DOD INTRuST.

Declarations of interest

The authors report no conflicts of interest.

Supplementary material

Supplemental data for this article can be accessed on the publisher’s website.

Additional information

Funding

This work was supported by the Medical Research and Materiel Command [Contract #W81XWH-08-2-0159 (Stein et al.), DOD INT].