Susan P. Proctor

Validation of Scales from the Deployment Risk and Resilience Inventory in a Sample of Operation Iraqi Freedom Veterans.

The Deployment Risk and Resilience Inventory (DRRI) is a suite of scales that can be used to assess deployment-related factors implicated in the health and well-being of military veterans. Although initial evidence for the reliability and validity of DRRI scales based on Gulf War veteran samples is encouraging, evidence with respect to a more contemporary cohort of Operation Iraqi Freedom (OIF) veterans is not available. Therefore, the primary goal of the present study was to validate scales from the DRRI in a large sample of OIF army personnel diversified in occupational and demographic characteristics. In general, results supported the use of these DRRI scales in this population. Internal consistency reliability estimates were quite strong. Additionally, support was obtained for criterion-related validity, as demonstrated by associations with mental and physical health measures, and discriminative validity, as demonstrated by differences between key military subgroups.

PTSD Symptom Increases in Iraq-Deployed Soldiers: Comparison With Nondeployed Soldiers and Associations With Baseline Symptoms, Deployment Experiences, and Postdeployment Stress

This prospective study examined: (a) the effects of Iraq War deployment versus non-deployment on pre- to postdeployment change in PTSD symptoms and (b) among deployed soldiers, associations of deployment/postdeployment stress exposures and baseline PTSD symptoms with PTSD symptom change. Seven hundred seventy-four U.S. Army soldiers completed self-report measures of stress exposure and PTSD symptom severity before and after Iraq deployment and were compared with 309 soldiers who did not deploy. Deployed soldiers, compared with non-deployed soldiers, reported increased PTSD symptom severity from Time 1 to Time 2. After controlling for baseline symptoms, deployment-related stressors contributed to longitudinal increases in PTSD symptoms. Combat severity was more strongly associated with symptom increases among active duty soldiers with higher baseline PTSD symptoms.

An investigation of the impact of posttraumatic stress disorder on physical health

In a large sample of Gulf War veterans (N = 2301) we examined the relations between PTSD symptoms assessed immediately upon returning from the Gulf War and self-reported health problems assessed 18–24 months later. PTSD symptomatology was predictive of self-reported health problems over time for both men and women veterans, even after the effects of combat exposure were removed from the analysis. Female veterans reported significantly more health problems than male veterans, however, there was no interactive effect of gender and PTSD on health problems. These findings provide further support for the theory that psychological response to stressors impacts health outcome.

Solvents and neurotoxicity

We describe the clinical evaluation of the nervous-system effects of solvent exposure. We review the current evidence in the epidemiological literature on neurotoxicological effects of solvents, and outline methods and issues to be taken into account in assessment of the patient whose symptoms may be related to solvent toxicity. Primary prevention of these disorders is essential, because treatment options are limited.

Understanding the neuropsychological consequences of deployment stress: a public health framework.

Complaints of neuropsychological dysfunction have emerged among subsets of military personnel after almost every major deployment involving western nations in recent history. Although deployments have been characterized by a range of neural risk factors, psychological stress is common to most prolonged deployments. This review uses a public health framework to address associations between deployment-related stress and neuropsychological performance. Specifically, the review covers mechanisms by which deployment-related psychological stress may affect neuropsychological functioning, considers the advantages and disadvantages of approaching the question from a public health perspective, and discusses how epidemiological research may sort out questions regarding course, cause, and effect.

Cumulative lead exposure and cognitive performance among elderly men.

Background: Recent evidence suggests that cumulative lead exposure among adults in nonoccupational settings can adversely affect cognitive function. Which cognitive domains are affected has not been explored in detail. Methods: We used nonlinear spline regressions and linear repeated-measures analysis to assess the association between scores on a battery of cognitive tests over time and both blood and bone lead concentrations in the Normative Aging Study, a cohort of community-dwelling elderly men. Bone lead was measured from 1991 through 1999 with K-shell x-ray fluorescence. A total of 1089 men with a mean (±standard deviation) age of 68.7 (±7.4) years with blood lead measurements, 761 of whom also had valid bone lead measurements, completed at least one of a battery of cognitive tests. Approximately 3.5 years later, 69% of the men had at least one repeat test. Cognitive testing was performed from 1993 through 2001. Results: On a cross-sectional basis, there was little association between blood or bone lead and cognitive test scores. Change in performance over time on virtually all tests worsened as bone lead increased, with the most robust effects on performance and reaction time scores on visuospatial/visuomotor tests. Conclusions: Low-level cumulative exposure to lead in nonoccupational settings may adversely affect cognitive function, particularly in the visuospatial/visuomotor domain.

Neuropsychological outcomes of mild traumatic brain injury, post-traumatic stress disorder and depression in Iraq-deployed US Army soldiers.

BACKGROUND Traumatic brain injury (TBI) is a concern of contemporary military deployments. Whether milder TBI leads to enduring impairment remains controversial. AIMS To determine the influence of deployment TBI, and post-traumatic stress disorder (PTSD) and depression symptoms on neuropsychological and functional outcomes. METHOD A sample of 760 US Army soldiers were assessed pre- and post-deployment. Outcomes included neuropsychological performances and subjective functional impairment. RESULTS In total, 9% of the participants reported (predominantly mild) TBI with loss of consciousness between pre- and post-deployment. At post-deployment, 17.6% of individuals with TBI screened positive for PTSD and 31.3% screened positive for depression. Before and after adjustment for psychiatric symptoms, TBI was significantly associated only with functional impairment. Both PTSD and depression symptoms adjusted for TBI were significantly associated with several neuropsychological performance deficits and functional impairment. CONCLUSIONS Milder TBI reported by deployed service members typically has limited lasting neuropsychological consequences; PTSD and depression are associated with more enduring cognitive compromise.

An Examination of Family Adjustment Among Operation Desert Storm Veterans

This study examined interrelationships among combat exposure, symptoms of posttraumatic stress disorder (PTSD), and family adjustment in a sample of male and female Operation Desert Storm veterans (N = 1,512). In structural equation models for both male and female veterans, higher combat exposure was associated with higher PTSD symptoms, which in turn were associated with poorer family adjustment, although these indirect effects did not reach statistical significance. The model for female veterans evidenced a significant direct negative association between combat exposure and family adjustment when it statistically accounted for PTSD symptoms. When the relative impacts of separate PTSD symptom groupings were examined, those reflecting withdrawal/numbing symptoms and arousal/lack of control symptoms significantly and indirectly accounted for the negative effects of combat exposure on family adjustment. Study findings indicate a number of possible pathways through which war-zone deployments negatively impact military families and suggest several avenues for future research.

Relationship of psychiatric status to Gulf War veterans' health problems.

OBJECTIVE A growing body of research has shown that there are important links between certain psychiatric disorders and health symptom reporting. Two disorders in particular (posttraumatic stress disorder (PTSD) and major depression) have been the most widely implicated to date, and this association has sometimes been used to explain the occurrence of ill-defined medical problems and increased somatic symptoms in certain groups, most recently Gulf War veterans. METHODS Structured psychiatric diagnostic interviews were used to examine the presence of major psychiatric (axis I) disorders and their relation to health symptom reporting in a well-characterized, stratified subset of Gulf War veterans and a non-Gulf-deployed veteran comparison group. RESULTS Rates of most psychiatric disorders were substantially lower than national comorbidity estimates, consistent with prior studies showing heightened physical and emotional well-being among active-duty military personnel. Rates of PTSD and major depression, however, were significantly elevated relative to the veteran comparison group. The diagnosis of PTSD showed a small but significant association with increased health symptom reports. However, nearly two-thirds of Gulf participants reporting moderate to high health symptoms had no axis I psychiatric diagnosis. CONCLUSIONS Results suggest that rates of psychiatric illness were generally low with the exception of PTSD and major depression. Although PTSD was associated with higher rates of reported health problems, this disorder did not entirely account for symptoms reported by participants. Factors other than psychiatric status may play a role in Gulf War health problems.

Residual cognitive deficits 50 years after lead poisoning during childhood.

The long term neurobehavioural consequences of childhood lead poisoning are not known. In this study adult subjects with a documented history of lead poisoning before age 4 and matched controls were examined with an abbreviated battery of neuropsychological tests including measures of attention, reasoning, memory, motor speed, and current mood. The subjects exposed to lead were inferior to controls on almost all of the cognitive tasks. This pattern of widespread deficits resembles that found in children evaluated at the time of acute exposure to lead rather than the more circumscribed pattern typically seen in adults exposed to lead. Despite having completed as many years of schooling as controls, the subjects exposed to lead were lower in lifetime occupational status. Within the exposed group, performance on the neuropsychological battery and occupational status were related, consistent with the presumed impact of limitations in neuropsychological functioning on everyday life. The results suggest that many subjects exposed to lead suffered acute encephalopathy in childhood which resolved into a chronic subclinical encephalopathy with associated cognitive dysfunction still evident in adulthood. These findings lend support to efforts to limit exposure to lead in childhood.