Clarifying the Relationship Between Mild Traumatic Brain Injury and Posttraumatic Stress Disorder Mina Dunnam, Ph.D. 1 ; Loretta S. Malta, Ph.D. 1 ; Nicole Mattila, M.A. 1 ; Kerry Donnelly, Ph.D., ABPP 2 ; James P. Donnelly, Ph.D. 3 ; Gar y C. Warner, Ph.D. 4 ; C. James Kittleson, Psy.D., ABPP 5 & Charles Bradshaw, Ph.D. 6 1 Stratton VA Medical Center, 2 VA Western New York Healthcare System, 3 The Center for Hospice & Palliative Care, 4 Canandaigua VA Medical Center, 5 Bath VA Medical Center, 6 Syracuse VA Medical Center Abstract Results Discussion Warzone-related mild traumatic brain injury (mTBI) has been associated with posttraumatic Stress Disorder (PTSD) in Veterans. PTSD symptoms include trauma re-experiencing (e.g., nightmares), avoidance and numbing symptoms (e.g., avoiding trauma reminders, blunted emotions), and hyperarousal symptoms (e.g., insomnia, poor concentration). Symptom overlap and similarities in neural abnormalities in PTSD and mTBI complicate diagnosis and treatment. The present study investigated the relationship between mTBI and PTSD symptoms. 296 current war veterans were assessed via the PTSD Checklist-Military Version (PCL-M) and a semi-structured interview to determine head injury status following deployment. Veterans with mTBI endorsed higher total PCL-M scores compared to Veterans without TBI, p<.001. A MANOVA of individual symptom scores found significantly higher scores across all PTSD symptoms, p <.001. Planned univariate tests found that TBI was associated with higher scores for each symptom, p <.001 to p <.005. A stepwise regression analysis of symptom predictors of TBI status found that nightmares and insomnia were the strongest links between mTBI and PTSD, p <.001. Results suggest that comorbid mTBI is associated with an exacerbation of PTSD symptoms, particularly hyperarousal and re- experiencing symptoms. Insomnia and nightmares can sometimes persist even after an otherwise successful course of exposure therapy for PTSD. Traditional exposure therapy for Veterans with mTBI and PTSD might need to be augmented with adjunctive interventions for insomnia and nightmares. Background Participants: 296 Veterans of Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF). Participants in the present study were recruited through the OEF/OIF Registry and via clinical referral. See Table 1 for demographic characteristics. Instruments: PTSD symptoms were assessed with the PTSD Checklist – Military Version 3 (PCL-M), a widely used inventory of self reported severity of monthly PTSD symptoms. Symptoms are endorsed according to how bothersome they are on a 5-point scale (1 = “not at all”; 5 = “extremely”). A semi-structured TBI interview, developed by a subset of the authors for a larger parent study on TBI, utilized Cifu et al.’s TBI diagnostic criteria 1, which include confirmation of: (1) a possible TBI event; (2) alteration of consciousness; and (3) post-concussive symptoms. The 22-item interview established the nature, probability, and severity of each deployment-related TBI reported by the participant. Any incident rated “very likely” or “almost certainly” to have resulted in a TBI was considered a positive diagnosis. Forty-five percent (n = 133) were diagnosed as having mTBI. Combat Veterans with mTBI presented with higher total PTSD symptom scores and with more severe individual symptoms. Nightmares, followed by insomnia, emerged as significant predictors of mTBI status after controlling for severity of other PTSD symptoms. The finding that mTBI was associated with insomnia was expected given that post-concussive syndrome includes sleep disturbance. Insomnia appeared to be the link between mTBI and PTSD hyperarousal and numbing symptoms, as these symptoms were excluded from the model after insomnia was included along with nightmares as a predictor. All five re- experiencing symptoms were more severe in Veterans with mTBI. The link between mTBI and trauma re-experiencing symptoms appeared to be mediated by nightmares. This symptom was the only re-experiencing symptom that significantly predicted mTBI. This finding is novel and warrants further investigation. Thought suppression has been associated with cognitive control abilities 4. Suppressing memories requires either the opportunity to engage in a distracting activity, which is not possible while sleeping, or the ability to redirect thoughts. Hence, impaired executive functioning could particularly exacerbate nightmares in Veterans with PTSD and mTBI. Our results also suggest that clinicians may need to be alert to the possibility that insomnia and nightmares may be more severe in Veterans with mTBI. Exposure therapy for Veterans with mTBI and PTSD might need to be augmented with adjunctive interventions for insomnia and nightmares. Comprehensive care provided in an integrated setting by a multidisciplinary team that shares a common understanding of TBI and PTSD may be the best hope for designing effective Polytrauma programs. Study limitations are that the sample was relatively small, predominantly male, and not racially/ethnically diverse. Participants were slightly older and better educated than other OEF/OIF Veteran samples. The study was also retrospective. Future prospective studies should continue to investigate the relationship between mTBI and PTSD. Contact: Mina Dunnam, Ph.D. at Stratton VA Medical Center, 113 Holland Ave, Albany, NY USA Methods References 1.Cifu, D., Bowles, A., Hurley, R. et al. Management of Concussion/mild Traumatic Brain Injury. US Department of Veterans Affairs and US Department of Defense. Washington, DC, The Management of Concussion/mTBI Working Group, Tanielian, T. & Jaycox, L.H. (Eds.). Invisible Wounds of War: Psychological and Cognitive Injuries, Their Consequences, and Services to Assist Recovery. Santa Monica, CA: RAND Corporation, Weathers, F., Litz, B., Herman, D., Huska, J., & Keane, T. The PTSD Checklist (PCL): Reliability, validity, and diagnostic utility. Paper presented at the Annual Convention of the International Society for Traumatic Stress Studies, San Antonio, October, Nixon RD, Nehmy T, Seymour M: The effect of cognitive load and hyperarousal on negative intrusive memories. Behaviour Research and Therapy, 2007; 45: An ANOVA found that participants diagnosed with mTBI had significantly more severe total PCL scores than those without mTBI: F(1, 294) = , p <.001. Mean (SD) total PCL scores = (15.41) for participants diagnosed with mTBI and (15.42) for participants without mTBI. A MANOVA found that participants with mTBI had significantly more severe individual symptom scores, Pillai’s Trace F(17, 278) = 3.532, p <.001, Planned univariate analyses found that mTBI was associated with significantly higher scores for each PTSD symptom. PTSD symptom scores and statistics from univariate tests are shown in Table 2. Many Veterans of the wars in Iraq and Afghanistan are dually affected by mild TBI and PTSD. 19.5% of military surveyed reported experiencing a TBI during deployment and 18.5% of US service members who have returned from Iraq and Afghanistan currently have PTSD or depression 1-2. Diagnosis, treatment, and management of mTBI and PTSD is complicated owing to their similarities in symptom presentation as well as the interplay between the two conditions. In the present study, we hypothesized that Veterans diagnosed with mTBI would present with more severe PTSD, particularly those symptoms that overlapped with post-concussive syndrome (i.e., problems with concentration, irritability, and sleep). We conducted analyses to identify which of the 17 PTSD symptoms were likely to be more severe in Veterans diagnosed with mTBI. Table 2. mTBI Status and Individual PTSD Symptom Scores Table 1. Demographic Data N (%) N = 296 Diagnosed with mTBI 133 (45) Males 275 (93) White Race 255 (86) Hispanic Ethnicity 16 (5) Education: Did not complete High School High School Diploma Completed Some College Bachelor’s Degree Completed greater than Bachelor’s Degree 6 (2) 79 (27) 168 (57) 28 (9) 15 (5) Mean (SD) Age32.63 (9.14). Final ModelΒSE Standardized Coefficient p <R2R2 PCL Nightmares PCL Insomnia Table 3. PTSD Symptoms that Predict mTBI Status PCL-M Item ScoresmTBI N = 133 Mean (SD) No mTBI N = 163 Mean (SD) F (17,278) p < Re-experiencing Symptoms Intrusive Memories3.40 (1.16)2.60 (1.16) Nightmares3.12 (1.27)2.19 (1.17) Reliving (Flashbacks)2.40 (1.19)1.85 (0.98) Emotional Reactions3.14 (1.17)2.45 (1.23) Physical Reactions2.89 (1.21)2.26 (1.22) Avoidance & Numbing Symptoms Avoidance (thoughts, feelings)3.35 (1.30)2.66 (1.39) Avoidance (situations)2.93 (1.38)2.31 (1.38) Posttraumatic Amnesia2.53 (1.26)2.11 (1.19) Loss of enjoyment/ motivation3.14 (1.23)2.47 (1.23) Estrangement3.32 (1.33)2.68 (1.26) Blunted emotions3.22 (1.45)2.42 (1.36) Feelings of Foreshortened Future 2.51 (1.43)1.92 (1.11) Hyperarousal Symptoms Insomnia4.00 (1.23)3.00 (1.44) Irritability3.56 (1.14)2.90 (1.24) Concentration problems3.50 (1.18)2.85 (1.20) Hypervigilance3.74 (1.11)3.07 (1.39) Exaggerated startle3.23 (1.22)2.60 (1.28) Procedures: P articipants completed neuropsychological evaluations consisting of the semi-structured interview, symptom self report questionnaires, including the PCL-M, and a neuropsychological test battery to assess impairment in cognitive functioning. Data Analyses: An ANOVA and a MANOVA were conducted to test whether participants with mTBI had more severe total PCL scores (ANOVA) and individual PTSD symptom scores (MANOVA). A stepwise regression analysis was conducted to identify which PTSD symptoms were most strongly associated with mTBI. The final results of the stepwise regression analysis are shown above in Table 3. On step 1, five symptoms significantly predicted mTBI: nightmares (p <.001), insomnia, impaired concentration (p =.030), blunted emotions (p =.036), and loss of enjoyment/ motivation (p =.046), with trends ((p <.10) for the symptoms of irritability, startle, and estrangement. On step 2, only the symptoms of nightmares and insomnia remained in the final model as significant, unique predictors of mTBI. The addition of insomnia to the model reduced the standardized coefficient for nightmares from.357, p <.001 to.238, p <.001; and significantly increased the R 2 value from.128 to.159. Hence, nightmares and insomnia predicted approximately 16% of the variance in mTBI diagnostic status.