RESUMEN
The interpersonal theory of suicide (Joiner, 2005) may help explain high suicide rates among veterans with posttraumatic stress disorder (PTSD). It suggests that suicidal ideation results from believing that one is a burden on others (i.e., perceived burdensomeness) and does not belong among family, friends, or other social groups (i.e., thwarted belongingness). Evidence-based PTSD treatments, including cognitive processing therapy (CPT), decrease suicidal ideation, potentially through changes in these two theory constructs. The current study examined whether (a) changes in PTSD severity and suicidal ideation and (b) changes in negative cognitions about self and suicidal ideation were indirectly associated through changes in perceived burdensomeness and thwarted belongingness across PTSD treatment. Participants (N = 107) were veterans in a residential treatment program who were diagnosed with full or subthreshold PTSD and received CPT. Changes in PTSD symptom severity and negative cognitions about self predicted changes in suicidal ideation, B = 0.18, p < .001 and B = 0.50, p < .001, respectively. Changes in PTSD symptom severity and negative cognitions about self were indirectly associated with suicidal ideation through changes in perceived burdensomeness, B = 0.16, 95% CI [0.07, 0.25]; B = 0.27, 95% CI [0.05, 0.50], but not thwarted belongingness, B = -0.002; 95% CI [-0.06, 0.06]; B = 0.06, 95% CI [-0.12, 0.21] in separate models. These findings suggest that residential CPT may be uniquely equipped to decrease suicidality by restructuring negative beliefs, including perceptions of being a burden on others, and/or by alleviating the objective burden of PTSD.
