Longitudinal relationship between onset of physical symptoms and functional impairment

Post-traumatic symptom severity mediates the association between combat exposure and suicidal ideation in veterans

OBJECTIVE

Previous studies of military veterans have produced mixed findings regarding whether combat exposure is directly related to suicidal ideation or is indirectly related to suicidal ideation via its influence on other factors. The present study used a longitudinal design to test the hypothesis that post-traumatic stress disorder (PTSD) symptom severity mediates the effect of combat exposure on suicidal ideation in veterans.

METHOD

Participants included 319 post-9/11 veterans (83.4% male; 42.1% White/52.1% Black; Mage  = 39.7) assessed at baseline, 6, and 12 months. Structural equation modeling and bootstrapped confidence intervals were employed to examine the direct and indirect relationships between combat exposure, suicidal ideation, and PTSD symptom severity.

RESULTS

Results from the mediation model, in which demographic variables and non-combat trauma were included as covariates, revealed that the indirect effect of combat exposure on suicidal ideation via PTSD symptom severity was statistically significant, accounting for 64.1% of the covariance between combat exposure and suicidal ideation.

CONCLUSIONS

This study provides longitudinal evidence that the effects of combat exposure on suicidal ideation are mediated by PTSD symptom severity, suggesting the importance of targeting such symptoms in treatment to mitigate suicide risk among veterans with combat exposure.

Interrelationships between symptom burden and health functioning and health care utilization among veterans with persistent physical symptoms

Background

Between 10 and 50% of primary care patients present with persistent physical symptoms (PPS). Patients with PPS tend to utilize excessive or inappropriate health care services, while being stuck in a deleterious cycle of inactivity, deconditioning, and further worsening of symptoms and disability. Since military deployment (relative to non-deployment) is associated with greater likelihood of PPS, we examined the interrelationships of health care utilization, symptom burden and functioning among a sample of recently deployed Veterans with new onset persistent physical symptoms.

Methods

This study analyzed a cohort of 790 U.S. soldiers who recently returned from deployment to Iraq or Afghanistan. Data for this analysis were obtained at pre- and post-deployment. We used moderation analyses to evaluate interactions between physical symptom burden and physical and mental health functioning and four types of health care utilization one-year after deployment, after adjusting for key baseline measures.

Results

Moderation analyses revealed significant triple interactions between physical symptom burden and health functioning and: primary care (F = 3.63 [2, 303], R²Δ = .02, p = 0.03), specialty care (F = 6.81 [2, 303] R²Δ =0.03, p < .001), allied therapy care (F = 3.76 [2, 302], R²Δ = .02, p = 0.02), but not mental health care (F = 1.82 [1, 303], R²Δ = .01, p = .16), one-year after deployment.

Conclusions

Among U.S. Veterans with newly emerging persistent physical symptoms one-year after deployment, increased physical symptom burden coupled with decreased physical and increased mental health functioning was associated with increased medical care use in the year after deployment. These findings support whole health initiatives aimed at improving health function/well-being, rather than merely symptom alleviation.