Functional Impairment as a Variable in Adjustment Post-Combat

Abstract

This study examined how functional impairment relates to postcombat adjustment over time, controlling for the influence of combat exposure. Analyses used sequential random coefficient models to examine 2 hypotheses: a) combat exposure and functional impairment predict the change in posttraumatic stress, depression, and anger/aggression symptoms during the first year postcombat; and b) combat exposure and functional impairment at reintegration predict symptom scores at 1 year postdeployment. A Brigade Combat Team completed surveys at reintegration, 4 months, and 12 months after a 1-year deployment to Iraq. Soldiers reporting high functional impairment at reintegration had higher symptoms at both follow-up periods, and functional impairment was a significant predictor of symptoms at the last time point, even after accounting for the influence of combat exposure. There was also an interaction effect, such that functional impairment exacerbated the impact of combat exposure on posttraumatic stress and anger/aggression symptoms at 12 months postdeployment.

• anger/aggression
• depression
• functional impairment
• postcombat recovery
• posttraumatic stress disorder

Notes

1 One of the effects of setting the intercept at the last time point is that the sign of the parameter estimate associated with the main effect for Time and Time-by-Predictor interactions will be the reverse of what one would assume. That is, if the parameter estimate associated with the main effect for Time is negative, this reflects a mean increase in outcome scores over time, whereas a positive sign would reflect a mean decrease in outcome scores across time.

2 A detailed review of the multivariate imputation procedure is available from the corresponding author.