Publications

2020

Fortenbaugh, F., Fonda, J., Fortier, C., Amick, M., Milberg, W., & McGlinchey, R. (2020). The Impact of Common Psychiatric and Behavioral Comorbidities on Functional Disability Across Time and Individuals in Post‐9/11 Veterans. Journal of Traumatic Stress.
Returning veterans often face multiple concurrent psychiatric and behavioral conditions that negatively impact reintegration into civilian life and are associated with functional disability. Understanding how conditions interact to negatively impact functioning is an important step toward developing holistic treatment approaches optimized for this population. This study utilized a cross-sectional and prospective longitudinal cohort design, applying regression algorithms to understand the relative contribution of common clinical issues to functional disability in U.S. veterans who served after the September 11, 2001 (9/11), terror attacks. Community-dwelling post-9/11 veterans (N = 397) completed detailed assessments, including common clinical condition diagnoses, combat experience, and demographics, which were used to predict functional disability (World Health Organization Disability Assessment Schedule); 205 participants were reassessed approximately 1-2 years after enrollment. Regression analyses showed a strong association between the predictor variables and functional disability, f 2 = 1.488. Validation analyses showed a high prediction ability of functional disability to independent samples, r = .719, and across time in the same individuals, r = .780. The strongest predictors included current posttraumatic stress disorder, depressive disorder, sleep disturbance, and pain diagnoses. These results demonstrate the importance of considering multiple common co-occurring conditions when assessing functional disability in post-9/11 veterans and suggest that certain syndromes contribute the most unique information to predicting functional disability with high confidence. As most U.S. veterans utilize private healthcare systems, these results have clinical utility for both Veterans Affairs and civilian healthcare practitioners in assessing and monitoring functional disability in post-9/11 veterans over time.
Fortier, C., Whitworth, J., Fonda, J., Currao, A., Beck, B., Levin, L., Esterman, M., Milberg, W., & McGlinchey, R. (2020). Early adolescent binge drinking increases risk of psychopathology in post-9/11 veterans and mild traumatic brain injury exacerbates symptom severity. Alcohol and Alcoholism.
AimsTo demonstrate that early adolescent binge drinking (BD) increases the risk for and/or severity of psychopathology in post-9/11 Veterans and determine if mild traumatic brain injury (mTBI) modifies risk.MethodsPost-9/11 Veterans (n = 375) were classified into two groups: 57 Veterans with a history of early adolescent BD (E-BD; age of onset 15) and 318 who did not BD until age 15 or older (late-BD or L-BD; age of onset ≥15). History of military mTBI and mental health disorders were also assessed following military service.ResultsLogistic regression and analysis of variance (ANOVA) analyses revealed that the E-BD’s had significantly higher prevalence of alcohol use disorders (AUDs) and more severe symptoms of AUD, substance use disorder (SUD), depression and stress. Two-way ANOVAs showed that history of military mTBI was differentially associated with posttraumatic stress disorder (PTSD) incidence and severity among Veterans who had engaged in early adolescent BD. Specifically, Veterans with a history of both early adolescent BD and military mTBI were at greater risk for a PTSD diagnosis and had more severe symptoms of PTSD than those with only a history of adolescent BD. The greater PTSD symptom severity in the comorbid group was driven by hyperarousal symptoms.ConclusionsA history of BD during early adolescence is prevalent among Veterans and is related to higher risk for AUD and more severe AUD, SUD, mood and stress symptoms later in life. Veterans with early BD and military mTBI showed greater incidence and severity of PTSD, indicating that mTBI, a common comorbidity among post-9/11 Veterans, exacerbates risk.
Wolf, E., Logue, M., Zhao, X., Daskalakis, N., Morrison, F., Escarfulleri, S., Stone, A., Schichman, S., McGlinchey, R., & Milberg, W. (2020). PTSD and the Klotho Longevity Gene: Evaluation of Longitudinal Effects on Inflammation via DNA Methylation. Psychoneuroendocrinology, 104656.
Background: Longevity gene klotho (KL) is associated with age-related phenotypes including lifespan, cardiometabolic disorders, cognition, and brain morphology, in part, by conferring protection against inflammation. We hypothesized that the KL/inflammation association might be altered in the presence of psychiatric stress and operate via epigenetic pathways. We examined KL polymorphisms, and their interaction with posttraumatic stress disorder (PTSD) symptoms, in association with KL DNA methylation in blood. We further examined KL DNA methylation as a predictor of longitudinal changes in a peripheral biomarker of inflammation (C-reactive protein; CRP).Methods: The sample comprised 309 white non-Hispanic military veterans (93.5 % male; mean age: 32 years, range: 19-65; 30 % PTSD per structured diagnostic interview); 111 were reassessed approximately two years later.Results: Analyses revealed a methylation quantitative trait locus at rs9527025 (C370S, previously implicated in numerous studies of aging) in association with a Cytosine-phosphate-Guanine site (cg00129557; B = -.65, p = 1.29 X 10-20), located within a DNase hypersensitivity site in the body of KL. There was also a rs9527025 x PTSD severity interaction (B = .004, p = .035) on methylation at this locus such that the minor allele was associated with reduced cg00129557 methylation in individuals with few or no PTSD symptoms while this effect was attenuated in those with elevated levels of PTSD. Path models revealed that methylation at cg00129557 was inversely associated with CRP over time (B = -.14, p = .005), controlling for baseline CRP. There was also an indirect effect of rs9527025 X PTSD on subsequent CRP via cg00129557 methylation (indirect B = -.002, p = .033).Conclusions: Results contribute to our understanding of the epigenetic correlates of inflammation in PTSD and suggest that KL methylation may be a mechanism by which KL genotype confers risk vs. resilience to accelerated aging in those experiencing traumatic stress.
Sydnor, V. J., Bouix, S., Pasternak, O., Hartl, E., Levin-Gleba, L., Reid, B., Tripodis, Y., Guenette, J. P., Kaufmann, D., Makris, N., Fortier, C., Salat, D., Rathi, Y., Milberg, W., McGlinchey, R., Shenton, M. E., & Koerte, I. K. (2020). Mild traumatic brain injury impacts associations between limbic system microstructure and post-traumatic stress disorder symptomatology. Neuroimage Clin, 26, 102190.
BACKGROUND: Post-traumatic stress disorder (PTSD) is a psychiatric disorder that afflicts many individuals, yet the neuropathological mechanisms that contribute to this disorder remain to be fully determined. Moreover, it is unclear how exposure to mild traumatic brain injury (mTBI), a condition that is often comorbid with PTSD, particularly among military personnel, affects the clinical and neurological presentation of PTSD. To address these issues, the present study explores relationships between PTSD symptom severity and the microstructure of limbic and paralimbic gray matter brain regions, as well as the impact of mTBI comorbidity on these relationships. METHODS: Structural and diffusion MRI data were acquired from 102 male veterans who were diagnosed with current PTSD. Diffusion data were analyzed with free-water imaging to quantify average CSF-corrected fractional anisotropy (FA) and mean diffusivity (MD) in 18 limbic and paralimbic gray matter regions. Associations between PTSD symptom severity and regional average dMRI measures were examined with repeated measures linear mixed models. Associations were studied separately in veterans with PTSD only, and in veterans with PTSD and a history of military mTBI. RESULTS: Analyses revealed that in the PTSD only cohort, more severe symptoms were associated with higher FA in the right amygdala-hippocampus complex, lower FA in the right cingulate cortex, and lower MD in the left medial orbitofrontal cortex. In the PTSD and mTBI cohort, more severe PTSD symptoms were associated with higher FA bilaterally in the amygdala-hippocampus complex, with higher FA bilaterally in the nucleus accumbens, with lower FA bilaterally in the cingulate cortex, and with higher MD in the right amygdala-hippocampus complex. CONCLUSIONS: These findings suggest that the microstructure of limbic and paralimbic brain regions may influence PTSD symptomatology. Further, given the additional associations observed between microstructure and symptom severity in veterans with head trauma, we speculate that mTBI may exacerbate the impact of brain microstructure on PTSD symptoms, especially within regions of the brain known to be vulnerable to chronic stress. A heightened sensitivity to the microstructural environment of the brain could partially explain why individuals with PTSD and mTBI comorbidity experience more severe symptoms and poorer illness prognoses than those without a history of brain injury. The relevance of these microstructural findings to the conceptualization of PTSD as being a disorder of stress-induced neuronal connectivity loss is discussed.
Whitworth, J. W., Hayes, S. M., Andrews, R., Fonda, J., Beck, B. M., Hanlon, L. B., Fortier, C., Milberg, W., & McGlinchey, R. (2020). Cardiorespiratory Fitness Is Associated With Better Cardiometabolic Health and Lower PTSD Severity in Post-9/11 Veterans. Mil Med, 185, Article 5-6.
INTRODUCTION: Post-traumatic stress disorder (PTSD) is associated with an increased risk of cardiovascular and metabolic diseases and physical inactivity. Cardiorespiratory fitness (CRF), which is modifiable by physical activity, is a strong independent predictor of cardiometabolic health. However, the relationship between CRF and cardiometabolic health in veterans with PTSD is unknown. Thus, this study aimed to explore the cross-sectional relationships among CRF, indices of cardiometabolic health (ie, HbA1c, blood lipids, blood pressure, waist-hip ratio, and body mass index), and PTSD severity in veterans with PTSD. MATERIALS AND METHODS: This study was approved by the local Institutional Review Board. All participants were informed of the study risks and provided consent prior to participation. Participants (n = 13) completed a cardiopulmonary exercise test, a fasting blood draw, and the Clinician Administered PTSD Scale. Correlations between CRF and cardiometabolic health were examined with Spearman's rank correlations, and differences in PTSD symptom severity were explored as a function of CRF (ie, low-to-moderate vs. high CRF), using multiple linear regression. RESULTS: Peak oxygen uptake ($\dot{\mathrm{V}}$O2peak) was correlated with high-density lipoproteins rho = 0.60, P = 0.04 and diastolic blood pressure rho = -0.56, P = 0.05. Ventilatory threshold was correlated with HbA1c rho = -0.61, P = 0.03 and diastolic blood pressure rho = -0.56, P = 0.05. Higher CRF was associated with lower total PTSD severity standardized β = -0.84, P = 0.01, adjusted R2 = 0.47, total Cluster C symptoms (avoidance/numbing) β = -0.71, P = 0.02, adjusted R2 = 0.49, and total Cluster D symptoms (hyperarousal) β = -0.89, P = 0.01, adjusted R2 = 0.41, while adjusting for age and smoking status. CONCLUSIONS: These preliminary findings suggest that CRF and by proxy physical activity may be important factors in understanding the increased risk of cardiovascular and metabolic disease associated with PTSD.