Relationship between processing speed and executive functioning performance among OEF/OIF veterans: implications for postdeployment rehabilitation.
BACKGROUND
Comorbid mild traumatic brain injury (mTBI) with posttraumatic stress disorder (PTSD) is a common clinical presentation among troops returning from Operation Enduring Freedom and Operation Iraqi Freedom (OEF/OIF). This study examined processing speed and executive functioning in a sample of OEF/OIF veterans who had sustained mTBI, a subset of whom also had comorbid PTSD.


METHODS
Fifty-three OEF/OIF veterans with a history of mTBI completed Wechsler Adult Intelligence Scale-III Symbol Search and Digit Symbol-Coding subscales, Stroop Word, color and color-word trials, and Trail Making Test, Parts A and B as part of a comprehensive neuropsychological test battery.


RESULTS
Excluding from analysis those who scored poorly on effort testing, multiple regression showed that measures of processing speed accounted for 43% of the variance in performance on the Trail Making Test, Part B and 50% of the variance in performance on the Stroop task. Significant differences in processing speed and executive functioning were found on the basis of presence of comorbid PTSD. Stroop Color (F = 9.27, df = 52, P < .004) and Stroop Color Word (F = 7.19, df = 52, P < .01) scores differed significantly between the groups. Those having comorbid PTSD (+TBI/+PTSD) scored significantly poorer than the mTBI-only group (+TBI/-PTSD). Implications for treatment of the comorbid conditions are discussed.
Nelson
Lonnie A
LA
Mental Health Service, Hunter Holmes McGuire Department of Veterans Affairs Medical Center, Richmond, Virginia, USA.
Yoash-Gantz
Ruth E
RE
Pickett
Treven C
TC
Campbell
Thomas A
TA
D000328:Adult; D001930:Brain Injuries / Q000150:complications / Q000523:psychology* / Q000534:rehabilitation*; D015897:Comorbidity; D006801:Humans; D008297:Male; D013313:Stress Disorders, Post-Traumatic / Q000150:complications / Q000523:psychology* / Q000534:rehabilitation*; D015599:Trauma Severity Indices; D014728:Veterans