Abstract
Objective: Examine relationships between self-perceived irritability, prospective memory, and quality of life (QOL) following mild traumatic brain injury (mTBI). Methods: 75 OEF/OIF/OND-era Veterans (56 deployment-related mTBI; 19 no history of TBI), were administered a battery of neuropsychological tests and self-report measures of mood and QOL. Self-perceived irritability was measured using the Neurobehavioral Symptom Inventory. Prospective memory (PM) was measured using the Memory for Intentions Test (MIST). Results: Self-perceived irritability was significantly higher for Veterans with, versus without, a history of deployment-related mTBI. Among Veterans with a history of mTBI, self-perceived irritability was inversely associated with PM performance, even after adjusting for PTSD severity. Greater self-perceived irritability was also associated with higher depressive symptoms and reduced QOL for perceived physical health, psychological health, social support, and environmental factors; however, only social support remained significant after adjusting for PTSD severity. Depression symptom severity was not significantly associated with PM, suggesting that PM may be uniquely related to self-perceived irritability rather than mood dysregulation more generally. Conclusions: Findings provide preliminary evidence of a relationship between PM and self-perceived irritability in Veterans with a history of mTBI. PM and irritability may be related via their mutual reliance on high-level cognitive control. Results illustrate possible cognitive and affective factors contributing to psychological and interpersonal challenges for this population. Future investigations with larger and more diverse samples are needed to replicate findings and explore potential mechanisms linking irritability and PM following mTBI.
Author note
This work was supported by the Department of Veterans Affairs Rehabilitation Research and Development Service Merit Review Award I01RX003087 (to ERP); VA Clinical Science Research and Development Career Development Award IK2 CX000516 (to KFP); VA Northwest MIRECC (ERP, KFP, HKR); and Department of Veterans Affairs Office of Academic Affiliations Advanced Fellowship Program in Mental Illness Research and Treatment and the VISN 21 MIRECC (MCO). Correspondence concerning this article may be sent to Marcela C. Otero, Ph.D. VA Palo Alto Health Care System, Mail Code 151Y MIRECC 3801 Miranda Avenue, Palo Alto, CA 94304. Phone: 1-650-493-5000. Email: [email protected] or Kathleen F. Pagulayan, Ph.D. VA Puget Sound Health Care System, Mail Code S-116-MIRECC 1660 South Columbian Way, Seattle, WA 98108. Phone: 1-206-768-5321. Email: [email protected].
Disclosure statement
No conflicts of interest are reported by any of the authors.
Data availability statement
The data that support the findings of this study may be available from the corresponding author [KFP] upon reasonable request and establishment of appropriate data use agreement.
Notes
1 Missing data on PM measure was due to the Memory for Intensions Test (MIST) being added
to the parent study at a later date compared to other neuropsychological measures. T-tests were conducted to examine any differences in demographic and clinical variables in participants with and without MIST scores. No significant group differences were found on demographic or clinical variables.
2 Results using listwise deletion were consistent with pairwise deletion findings.