Article

The ongoing controversy whether mild traumatic brain injury (TBI) can
cause chronic sequel is partly due to diagnostic limitations. Diagnosing mild TBI
is particularly challenging when assessment is not immediate, and when informed,
first responder documentation or witness corroboration is absent. In this common
scenario, the diagnosis is made entirely on self-report of an initial period of
alteration of consciousness (AOC) associated with a plausible injury mechanism.
Yet, there is scant published empirical guidance on methods for accurately
detecting historical AOC. OBJECTIVES: To assess the value that recalled AOC
symptoms collected via questionnaire have in evaluating individuals exposed to
blast during recent military deployment. More specifically, to analyze the
concrete AOC items (those signifying unconsciousness and/or posttraumatic
amnesia) for their (1) frequency and distribution of positive versus negative
responses, (2) interitem agreement, and (3) relation to current neuropsychiatric
symptoms including those consistent with postconcussion syndrome (PCS).
PARTICIPANTS: Eighty-seven active duty or Veteran subjects who experienced acute
effects from a blast within the past 2 years while deployed for Operations
Enduring and Iraqi Freedom. RESULTS: : Twenty-nine participants (33.3%) responded
positively to at least 1 of 3 concrete AOC items: gap in memory (17.2%), memory
not continuous (13.8%), and/or told by observer they had loss of consciousness
(20.7%). Alteration of consciousness items were associated with but
nondiscriminate of current symptom distress on standardized measures of PCS
(Rivermead Postconcussion Symptom Questionnaire), posttraumatic stress disorder
(PTSD; PTSD Checklist), depression (Centers for Epidemiological Studies
Depression Scale), and pain (Short Form McGill Pain Questionnaire). CONCLUSIONS:
The positive association between subjects' questionnaire-based AOC item responses
and current symptom complex measures suggests that mild TBI has a role in the
development of chronic neuropsychiatric symptoms after blast exposure. The lack
of symptom- complex discrimination, and the inconsistencies found in subjects'
item responses suggest that a structured interview may improve postacute
diagnostic specificity for mild TBI.

Langue : ANGLAIS