Assessing neurocognitive outcomes in PTSD: a multilevel meta-analytical approach

Background: Evidence supporting the association between posttraumatic stress disorder (PTSD) and cognitive impairment is accumulating. However, less is known about which factors influence this association. Objective: The aims of this meta-analysis were to (1) elucidate the association between PTSD and a broad spectrum of cognitive impairment, including the risk of developing neurocognitive disorder (NCD) later in life, using a multilevel meta-analytic approach, and (2) identify potential moderating factors of this association by examining the effects of age (20-39, 40-59, 60+), study design (cross-sectional or longitudinal), study population (war-exposed populations/veterans or the general population), neurocognitive outcome assessed (i.e. a diagnosis of NCD or type of cognitive domain as classified according to A Compendium of Neuropsychological tests), gender (>= 50% women or <50% women), study quality (high vs low), type of PTSD measure (self-report or clinical diagnosis), as well as the presence of comorbidities such as traumatic brain injury (TBI), depression, and substance use (all coded as either present or absent). Method: Peer-reviewed studies on this topic were extracted from PubMed and Web of Science with predetermined keywords and criteria. In total, 53 articles met the criteria. Hedge's g effect sizes were calculated for each study and a three-level random effect meta-analysis conducted. Results: After accounting for publication bias, the results suggested a significant association between PTSD and cognitive impairment, g = 0.13 (95% CI: 0.10-0.17), indicating a small effect. This association was consistent across all examined moderators, including various neurocognitive outcomes, age, gender, study design, study population, study quality, type of PTSD measure, and comorbidities such as depression, substance use, and TBI. Conclusions: These findings collectively suggest that PTSD is associated with both cognitive impairment and NCD. This emphasizes the need for early intervention (including prevention strategies) of PTSD, alongside monitoring cognitive function in affected individuals.