Proctor Susan P, Heaton Kristin J, Dos Santos Kathryn Dutille, Rosenman Erik S, Heeren Timothy
Military Performance Division, US Army Research Institute of Environmental Medicine, Kansas St, Building 42, Natick, MA 01760, United States.
Scand J Work Environ Health. 2009 Oct;35(5):349-60. doi: 10.5271/sjweh.1348.
The present study examined the impact of deployment on neuropsychological functioning and mood in Army National Guard personnel. We hypothesized that deployment on a peacekeeping mission, compared to non-deployment, would result in reduced proficiencies in neuropsychological performance and negative mood changes, and that such changes would relate to working in a high-strain job (high demands/low control), in accordance with Karasek's demand-control model.
This prospective cohort study involved 119 male soldiers (67 participants examined before and after deployment to the Bosnia operational theatre and 52 non-deployed soldiers assessed twice over a comparable period).
Unit-level adjusted, multivariate analyses found that deployed soldiers, compared to their non-deployed counterparts, demonstrated reduced proficiency in tasks involving motor speed [unstandardized coefficient B= -3.88, 95% confidence interval (95% CI) -6.38- -1.39; B= -3.84, 95% CI -5.55- -2.14; dominant and non-dominant hand, respectively] and sustained attention (B=0.031, 95% CI 0.009-0.054), along with decreased vigor (B= -2.71, 95% CI -3.63- -1.77). Deployed soldiers also showed improved proficiency in a working-memory task (B= -0.098, 95% CI -0.136- -0.060) with less depression symptomatology (B= -3.19, 95% CI -5.26- -1.13). Work stress levels increased over time in both deployed and non-deployed groups, but observed deployment effects remained significant after accounting for a high-strain job.
The observed change in performance associated with peacekeeping deployment compared to non-deployment (slowed processing speed, reduced motor speed and reported vigor, together with improved proficiency in a working memory task) suggests an adaptive response to mission occupational stressors. This pattern does not appear to be influenced by working in a high-strain job. Further study is required to examine whether these results reflect transient or permanent changes in functioning.
