Unwanted memories of assault: what intrusion characteristics are associated with PTSD?

• Published in: Behaviour research and therapy Vol. 43; no. 5; pp. 613 - 628
• Main Authors: Michael, T., Ehlers, A., Halligan, S.L., Clark, D.M.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.05.2005; Elsevier Science; Elsevier Science Ltd
• Subjects: Adult; Adult and adolescent clinical studies; Aged; Anxiety disorders. Neuroses; Assaults; Biological and medical sciences; Cross-Sectional Studies; Female; Humans; Intrusions; Male; Medical sciences; Memory; Middle Aged; Post traumatic stress disorder; Posttraumatic stress disorder; Predictors of PTSD; Prospective Studies; Psychiatric Status Rating Scales; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Rumination; Screening; Sensitivity and Specificity; Statistics, Nonparametric; Stress Disorders, Post-Traumatic - diagnosis; Stress Disorders, Post-Traumatic - psychology; Survivors; Trauma memories; Violence; Trauma memories; Intrusions; Screening; Posttraumatic stress disorder; Rumination; Predictors of PTSD; Human; Posttraumatic syndrome; Memory; Recollection; Anxiety disorder; Medical screening; Trauma; Stress; Intrusive thought; Predictive factor
• ISSN: 0005-7967; 1873-622X
• DOI: 10.1016/j.brat.2004.04.006

Intrusive memories are common in the immediate aftermath of traumatic events, but neither their presence or frequency are good predictors of the persistence of posttraumatic stress disorder (PTSD). Two studies of assault survivors, a cross-sectional study (N=81) and a 6-month prospective longitudinal study (N=73), explored whether characteristics of the intrusive memories improve the prediction. Intrusion characteristics were assessed with an Intrusion Interview and an Intrusion Provocation Task. The distress caused by the intrusions, their “here and now” quality, and their lack of a context predicted PTSD severity. The presence of intrusive memories only explained 9% of the variance of PTSD severity at 6 months after assault. Among survivors with intrusions, intrusion frequency only explained 8% of the variance of PTSD symptom severity at 6 months. Nowness, distress and lack of context explained an additional 43% of the variance. These intrusion characteristics also predicted PTSD severity at 6 months over and above what could be predicted from PTSD diagnostic status at initial assessment. Further predictors of PTSD severity were rumination about the intrusive memories, and the ease and persistence with which intrusive memories could be triggered by photographs depicting assaults. The results have implications for the early identification of trauma survivors at risk of chronic PTSD.