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Social Psychiatry and Psychiatric Epidemiology

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Open Access 01-04-2019 | Post-Traumatic Stress Disorder | Original Paper

Low-level cognitive ability in young adulthood and other risk factors of depression in an observational cohort study among deployed Danish soldiers

Authors: Lars Ravnborg Nissen, Karen-Inge Karstoft, Mia Sadowa Vedtofte, Anni Brit Sternhagen Nielsen, Merete Osler, Erik Lykke Mortensen, Gunhild Tidemann Christensen, Søren Bo Andersen

Published in: Social Psychiatry and Psychiatric Epidemiology | Issue 4/2019

Abstract

Purpose

Evidence exists of an association between pre-morbid lower cognitive ability and higher risk of hospitalization for depressive disorder in civilian cohorts. The purpose of this study was to examine the relationship of cognitive ability at conscription with post-deployment depression and the influence of (1) baseline factors: age, gender, and pre-deployment educational level, (2) deployment-related factors: e.g., war-zone stress and social support, and (3) co-morbid PTSD.

Methods

An observational cohort study linking conscription board registry data with post-deployment self-report data. The study population consisted of Danish Army military personnel deployed to different war zones from 1997 to 2015. The association between cognitive ability at conscription and post-deployment depression was analyzed using repeated-measure logistic regression models.

Results

Study population totaled 9716 with a total of 13,371 deployments. Low-level cognitive ability at conscription was found to be weakly associated with post-deployment probable depression after adjustment for more important risk factors like gender, education, and deployment-related factors [odds ratio (OR) 0.93, 95% confidence interval (CI) 0.88–0.99]. The co-occurrence rate with PTSD was nearly 60%. When adding co-morbid PTSD as an independent variable, the association between cognitive ability and probable depression became insignificant, OR 0.95, CI 0.89–1.02.

Conclusions

Low cognitive ability at conscription is a risk factor for depression among returning military personnel, but unimportant compared to gender, education, and deployment-related factors. Part of this effect may be related to co-morbid PTSD. Use of cognitive ability score as an isolated selection tool cannot be recommended because of low predictive performance.

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Title: Low-level cognitive ability in young adulthood and other risk factors of depression in an observational cohort study among deployed Danish soldiers
Authors: Lars Ravnborg Nissen
Karen-Inge Karstoft
Mia Sadowa Vedtofte
Anni Brit Sternhagen Nielsen
Merete Osler
Erik Lykke Mortensen
Gunhild Tidemann Christensen
Søren Bo Andersen
Publication date: 01-04-2019
Publisher: Springer Berlin Heidelberg
Keywords: Post-Traumatic Stress Disorder
Mood Disorders
Affective Disorder
Published in: Social Psychiatry and Psychiatric Epidemiology / Issue 4/2019
Print ISSN: 0933-7954
Electronic ISSN: 1433-9285
DOI: https://doi.org/10.1007/s00127-018-1648-1

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Low-level cognitive ability in young adulthood and other risk factors of depression in an observational cohort study among deployed Danish soldiers

Abstract

Purpose

Methods

Results

Conclusions

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Purpose

Methods

Results

Conclusions

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