Internal entrapment and fearlessness about death as precipitants of suicidal thoughts and planning in the context of post-traumatic stress disorder

Background
The relationship between post-traumatic stress disorder (PTSD) and suicidal thoughts and behaviors (STB) has been extensively studied but explanatory mechanisms remain inconclusive. Entrapment is one variable that evinces a mechanistic relationship with PTSD and STB. The current study examined the indirect effect of PTSD screen on suicide ideation (SI), planning, and likelihood of future suicide attempt through internal (IE) and external entrapment (EE), moderated by levels of fearlessness about death (FAD).
Method
The cross-sectional sample consisted of military service members and civilians recruited from primary care clinics across the United States (N = 2690).
Results
Moderated mediation models indicated an indirect relationship between a positive PTSD screen, past-month SI, and past-month suicide planning through IE but not EE at low, moderate, and high levels of FAD. These relationships were replicated for the association between positive PTSD screen and concurrent self-rated likelihood of a future suicide attempt through both IE and EE at moderate and high levels of FAD.
Conclusions
Phenomenological implications are discussed, including IE as a mechanism of action in the PTSD/SI pathway and FAD as necessary to potentiate suicidal planning for those experiencing IE.