Background: Qualitative review papers have indicated that verbal memory impairment is found to be the most consistent cognitive impairment related to PTSD. These review papers have used qualitative methods to describe the effects, and consequently they have not been able to estimate the strength of the memory-PTSD association.
Methods: This meta-analysis of 28 studies examined the empirical evidence for this relationship, and factors affecting the results.
Results: Overall, the results showed medium effect sizes in patients with PTSD compared to controls on verbal memory across studies. Marked impairment was found in the patient groups compared to healthy controls, while modest impairment was found compared to exposed non-PTSD controls. Meta-analyses found strongest effects in war veterans compared to sexual and physical assault related PTSD. Rather unexpectedly no effect was found for the sexually abused PTSD groups compared to exposed controls. The analyses further showed that the effect was dependent on the test procedures used. The studies using WMS and AVLT had stronger effects than studies using CVLT.
Limitations: Insufficient data were available to analyze a more complete attention-memory profile.
Conclusions: This meta-analysis confirms that verbal memory impairment is present in adults with PTSD, and they are consistent across studies. This impairment should be the focus of work in clinical settings.