Clinical correlates of retrograde amnesia in mild traumatic brain injury.

PRIMARY

OBJECTIVE

The purpose of this study was to examine the clinical significance of retrograde amnesia (RA) in patients with acute mild traumatic brain injuries (MTBI).

METHODS AND PROCEDURES: An emergency department sample of patients (n = 75), aged 18-60 years, with no pre-morbid medical or psychiatric conditions, who met the WHO criteria for MTBI were enrolled in this prospective, descriptive, follow-up study. This study examined the presence and duration of RA in relation to socio-demographics, MTBI severity markers including neuroimaging (CT, MRI) and clinical outcomes (Rivermead post-concussion symptoms questionnaire, post-concussion syndrome (PCS) diagnosis and return to work (RTW) status) at 2 weeks, 1 month and 6 months post-injury.

MAIN OUTCOMES AND

RESULTS

GCS scores and duration of post-traumatic amnesia (PTA) were related to RA. Those with GCS scores of 14 vs. 15 were more likely to have RA (χ(2)(1) = 13.70, p < 0.0001) and a longer duration (Mann-Whitney U = 56.0, p < 0.0001, d = 1.15) of RA. The duration of RA and PTA correlated positively (Spearman ρ(75) = 0.42, p < 0.0001) and those with RA had longer durations of PTA (Mann-Whitney U = 228.5, p = 0.001, d = 1.21). During the follow-up, the presence and duration of RA were not significantly associated with PCS diagnosis or time to RTW.

CONCLUSIONS

In this study, the presence and duration of RA was not associated with outcome.