Trauma at the hands of another: distinguishing PTSD patterns following intimate and nonintimate interpersonal and noninterpersonal trauma in a nationally representative sample.

Objective: Interpersonal trauma and violence is currently considered a global public health emergency. However, studies have not differentiated between intimate interpersonal trauma and nonintimate interpersonal trauma in their impact on posttraumatic stress disorder (PTSD) symptomatology. This cross-sectional study based on epidemiologic data examined the differential likelihoods of endorsing PTSD symptoms following 3 categories of trauma: noninterpersonal (eg, accidents, natural disasters), nonintimate interpersonal (physical assaults perpetrated by nonintimates), and intimate interpersonal (physical assaults perpetrated by intimates or caregivers and sexual assaults).

Method: DSM-IV PTSD symptom data drawn from a weighted subsample (N = 1,012) of people reporting "most severe" reactions following one of the above types of trauma in the 2007 Australian National Survey of Mental Health and Well-Being (NSMHWB) were analyzed using binary logistic regression.

Results: Participants reporting intimate interpersonal compared with noninterpersonal trauma were significantly (P < .001) more likely to endorse core symptoms (intrusive reexperiencing, avoidance of reminders, hypervigilance, and startle response) of PTSD. The intimate interpersonal trauma group members were significantly more likely than the nonintimate interpersonal trauma group members to endorse distress at reminders (odds ratio [OR] = 3.2; P < .001; 99.7% CI, 1.3-7.9), avoiding thinking about the event (OR = 3.2; P < .001; 99.7% CI, 1.3-7.7), detachment from others (OR = 3.2; P < .001; 99.7% CI, 1.2-8.9), and restricted affect (OR = 4.1; P < .001; 99.7% CI, 1.5-11.3). Participants reporting nonintimate interpersonal and noninterpersonal traumas did not significantly differ except in endorsement of behavioral avoidance (OR = 2.8; P < .001; 99.7% CI, 1.2-6.6), hypervigilance (OR = 2.5; P = .002; 99.7% CI, 1.0-6.3), and exaggerated startle response (OR = 3.5; P < .001; 99.7% CI, 1.7-7.4).

Conclusions: Survivors of intimate trauma appear to experience particularly severe intrusive memories and reminders of past trauma and suppression of emotional responsivity. The unique impact of interpersonal trauma, however, intimate or otherwise, compared with noninterpersonal trauma, is the experience of an environment as unsafe and unpredictable, due to the potential of human threat. Such findings have significant implications for the assessment of and interventions for survivors of interpersonal violence.