A longitudinal study of pain and pain catastrophizing in a cohort of National Guard troops at risk for PTSD

Abstract

A recent cross-sectional study of National Guard troops found that pain and pain catastrophizing were prevalent and highly correlated with posttraumatic stress disorder (PTSD). At issue in the present study was whether pain and catastrophizing before military deployment could account for individual differences in PTSD symptoms after deployment. An anonymous survey was administered to a population sample of New Jersey National Guard troops before they were sent overseas and again when they returned home (1 year later). The survey included a validated PTSD screening questionnaire, numerical ratings of pain intensity, and a measure of pain catastrophizing. A cohort of 922 National Guard members completed the survey before and after deployment. An uncontrolled analysis indicated that pain and catastrophizing before deployment were significantly but modestly associated with PTSD symptoms after deployment (accounting for 4.5% and 1.3% of the variance, respectively). A hierarchical regression model that controlled for sex, preexisting PTSD symptoms, and recent combat found that pain but not pain catastrophizing explained variance in postdeployment PTSD. The size of the effect, however, was negligible (0.8%, p<.01). Consistent with previous research, a cross-sectional analysis revealed that postdeployment pain and catastrophizing successfully accounted for unique variance in postdeployment PTSD. The failure of longitudinal predictors in the present study, therefore, cannot be attributed to insensitive screening instruments. These findings offer little or no support for the hypothesis that predeployment pain and catastrophizing can account for individual differences in PTSD after exposure to combat trauma.