Cognitive ability and risk of post-traumatic stress disorder after military deployment: an observational cohort study

TY - JOUR

T1 - Cognitive ability and risk of post-traumatic stress disorder after military deployment

T2 - an observational cohort study

AU - Nissen, Lars R.

AU - Karstoft, Karen-Inge

AU - Vedtofte, Mia S.

AU - Nielsen, Anni B. S.

AU - Osler, Merete

AU - Mortensen, Erik L.

AU - Christensen, Gunhild T.

AU - Andersen, Søren B.

PY - 2017/11/1

Y1 - 2017/11/1

N2 - Background: Studies of the association between pre-deployment cognitive ability and post-deployment post-traumatic stress disorder (PTSD) have shown mixed results. Aims: To study the inflence of pre-deployment cognitive ability on PTSD symptoms 6-8 months post-deployment in a large population while controlling for pre-deployment education and deployment-related variables. Method: Study linking prospective pre-deployment conscription board data with post-deployment self-reported data in 9695 Danish Army personnel deployed to different war zones in 1997-2013. The association between pre-deployment cognitive ability and post-deployment PTSD was investigated using repeated-measure logistic regression models. Two models with cognitive ability score as the main exposure variable were created (model 1 and model 2). Model 1 was only adjusted for pre-deployment variables, while model 2 was adjusted for both pre-deployment and deployment-related variables. Results: When including only variables recorded pre-deployment (cognitive ability score and educational level) and gender (model 1), all variables predicted post-deployment PTSD. When deployment-related variables were added (model 2), this was no longer the case for cognitive ability score. However, when educational level was removed from the model adjusted for deployment-related variables, the association between cognitive ability and post-deployment PTSD became significant. Conclusions: Pre-deployment lower cognitive ability did not predict post-deployment PTSD independently of educational level after adjustment for deployment-related variables.

AB - Background: Studies of the association between pre-deployment cognitive ability and post-deployment post-traumatic stress disorder (PTSD) have shown mixed results. Aims: To study the inflence of pre-deployment cognitive ability on PTSD symptoms 6-8 months post-deployment in a large population while controlling for pre-deployment education and deployment-related variables. Method: Study linking prospective pre-deployment conscription board data with post-deployment self-reported data in 9695 Danish Army personnel deployed to different war zones in 1997-2013. The association between pre-deployment cognitive ability and post-deployment PTSD was investigated using repeated-measure logistic regression models. Two models with cognitive ability score as the main exposure variable were created (model 1 and model 2). Model 1 was only adjusted for pre-deployment variables, while model 2 was adjusted for both pre-deployment and deployment-related variables. Results: When including only variables recorded pre-deployment (cognitive ability score and educational level) and gender (model 1), all variables predicted post-deployment PTSD. When deployment-related variables were added (model 2), this was no longer the case for cognitive ability score. However, when educational level was removed from the model adjusted for deployment-related variables, the association between cognitive ability and post-deployment PTSD became significant. Conclusions: Pre-deployment lower cognitive ability did not predict post-deployment PTSD independently of educational level after adjustment for deployment-related variables.

KW - Journal Article

U2 - 10.1192/bjpo.bp.117.005736

DO - 10.1192/bjpo.bp.117.005736

M3 - Journal article

C2 - 29163983

SN - 2056-4724

VL - 3

SP - 274

EP - 280

JO - British Journal of Psychiatry Open

JF - British Journal of Psychiatry Open

IS - 6

ER -