Kelly A. Stearns-Yoder

Combined Toxoplasma gondii seropositivity and high blood kynurenine – Linked with nonfatal suicidal self-directed violence in patients with schizophrenia

Toxoplasma gondii (T. gondii) chronic infection and elevated kynurenine (KYN) levels have been individually associated with non-fatal suicidal self-directed violence (NF-SSDV). We aimed to test the hypothesis that the association between T. gondii seropositivity and history of NF-SSDV would be stronger in schizophrenia patients with high plasma KYN levels than in those with lower KYN levels. We measured anti-T. gondii IgG antibodies and plasma KYN in 950 patients with schizophrenia, and used logistic regression to evaluate the relationship between NF-SSDV and KYN in patients who were either seropositive or seronegative for T. gondii. For those with KYN levels in the upper 25th percentile, the unadjusted odds ratio for the association between NF-SSDV history and KYN in T. gondii seropositive patients was 1.63 (95% CI 1.01 to 2.66), p = 0.048; the adjusted odds ratio was 1.95 (95% CI 1.15 to 3.30), p = 0.014. Plasma KYN was not associated with a history of NF-SSDV in T. gondii seronegative patients. The results suggest that T. gondii and KYN may have a nonlinear cumulative effect on the risk of NF-SSDV among those with schizophrenia. If confirmed by future longitudinal studies, this result is expected to have both theoretical and clinical implications for the prevention and treatment of suicidal behavior.

Kynurenine and Tryptophan Levels in Patients with Schizophrenia and Elevated Antigliadin Immunoglobulin G Antibodies

Objective Several studies have reported an association between nonceliac gluten sensitivity and schizophrenia. Immune and kynurenine (KYN) pathways have also been implicated in the pathophysiology of schizophrenia, and certain proinflammatory immune mediators may increase KYN and reduce tryptophan (TRP) levels. Methods We measured serum antigliadin immunoglobulin G (IgG), KYN, and TRP in 950 patients with schizophrenia. Patients with antibody level at the 90th percentile or higher of control participants (21.9% of all patients) were classified as having elevated antigliadin IgG. Independent t tests and linear regression models were used to compare TRP, KYN, and KYN-TRP ratio (indicator of TRP metabolism) between patients with and those without elevated antigliadin IgG. The correlation between antigliadin IgG and TRP, KYN, and the ratio was also evaluated in the patients. Results KYN and KYN-TRP ratio were higher in patients with elevated antigliadin IgG (geometric mean [standard deviation {SD}] = 2.65 [0.25] µmol/L versus 2.25 [0.23] µmol/L [p < .001] and 0.05 [0.26] versus 0.04 [0.25; p = .001] respectively), findings robust to adjustment for potential demographic and clinical confounders. Antigliadin IgG positively correlated with KYN and KYN-TRP ratio (r = 0.12, p < .001; r = 0.11, p = .002). TRP did not differ between the two groups and did not correlate with antigliadin IgG. Conclusions Our results connect nonceliac gluten sensitivity with the KYN pathway of TRP metabolism in psychotic illness and hint toward potential individualized treatment targets.

Growing literature but limited evidence: A systematic review regarding prebiotic and probiotic interventions for those with traumatic brain injury and/or posttraumatic stress disorder

Traumatic brain injury (TBI) is highly prevalent among a wide range of populations, including civilians, military personnel, and Veterans. TBI sequelae may be further exacerbated by symptoms associated with frequently occurring comorbid psychiatric conditions, including posttraumatic stress disorder (PTSD). This is particularly true among the population of military personnel from recent conflicts in Iraq and Afghanistan, with a history of mild TBI (mTBI) and PTSD. The need for efficacious treatments for TBI and comorbid PTSD is significant, and evidence-based interventions for these frequently co-occurring conditions are limited. Based on findings suggesting that inflammation may be an underlying mechanism of both conditions, anti-inflammatory/immunoregulatory agents, including probiotics, may represent a novel strategy to treat TBI and/or PTSD-related symptoms. The focus of this systematic review was to identify and evaluate existing research regarding prebiotic and probiotic interventions for the populations of individuals with a history of TBI and/or PTSD. Only 4 studies were identified (3 severe TBI, 1 PTSD, 0 co-occurring TBI and PTSD). Although findings suggested some promise, work in this area is nascent and results to date do not support some claims within the extensive coverage of probiotics in the popular press.

A qualitative study of sleep-wake disturbance among veterans with post-acute moderate to severe traumatic brain injury

Objective:Examine sleep-wake disturbance (SWD) characteristics, factors, consequences, and management strategies from the perspective of veterans with chronic stage, moderate/severe traumatic brain injury (TBI). Setting:VA Medical Center, Rocky Mountain. US Participants:Nineteen male veterans with post–acute TBI and SWD in the VA Health Administration. Design:Qualitative descriptive. Measures:Semistructured interviews, Ohio State University TBI-Identification Method, Insomnia Severity Index. Results:Two main dimensions emerged: “Messed up sleep” and Surviving and Managing SWD. Sleep-wake disturbance has long-term multidimensional features, etiology, consequences, and practice implications. Although SWD may not be consistently discussed with providers, the problem appears to be pervasive in many aspects of the lives of the informants. Difficulty falling asleep, frequent awakenings, and poor sleep quality were common symptoms that were described as intrusive, isolating, and difficult to self-manage. Veterans discussed a host of physical symptoms, mental health issues, environmental, and behavioral factors that contributed to SWD. Medications, sleep apnea treatment, and self-imposed isolation were frequent management strategies. Veterans expressed a willingness to try new approaches and work with providers. Conclusion:Sleep-wake disturbance among veterans with chronic stage TBI is a multidimensional phenomenon with interplay between comorbidities, contributing factors, effects on functioning, and sleep management strategies. Implications for practice include early and routine evaluation, monitoring, and treatment of SWD. Research is needed to test interventions that address SWD and common TBI comorbidities.

Exploring service dogs for rehabilitation of veterans with PTSD: A microbiome perspective.

Purpose/Objective: Recently, there has been an increase in the use of therapy animals, often dogs, to assist individuals with challenges associated with managing stressful social situations (i.e., psychological rehabilitation). Potential applications are wide-ranging from elementary schools to airports to hospitals. Here we present an overview of the present knowledge and provide recommendations for future research aimed at exploring the impact of therapy dogs on the rehabilitation of Veterans with posttraumatic stress disorder (PTSD) with a focus on the microbiome. Research Method/Design: In this review we searched the literature for studies that were conducted involving Veterans and service dogs. Because of the limited number of studies, we conducted a nonsystematic review to include the topics of the microbiome and psychological mechanisms that may play a role in rehabilitation of Veterans with dogs. Results: Whether dogs can be used as an intervention to increase function among those with PTSD remains a question. Nonetheless, it has been suggested that dog ownership may improve mental health outcomes via multiple mechanisms, such as decreasing social isolation and increasing physical activity and exposure to green spaces. The presence of a dog in the home may alter the human inhabitants’ microbiomes, thereby, potentially providing an additional mechanism through which service dogs may influence human health and well-being. Conclusions/Implications: Theoretically, the use of service dogs for rehabilitation of Veterans with PTSD could improve mental health outcomes. To the best of our knowledge the impact that therapy dogs have on the microbiome of the owners, as well as their built environments, has yet to be explored.

Traumatic brain injury, psychiatric diagnoses, and suicide risk among Veterans seeking services related to homelessness

ABSTRACT Objectives: To explore the differences in negative psychiatric outcomes (i.e. type and number of psychiatric diagnoses, suicide risk) among Veterans with and without a history of traumatic brain injury (TBI) seeking homeless services. Methods: Observational design with data collected at one time-point. Veterans seeking homeless services from two Veteran Affairs (VA) Medical Centres completed study measures (n = 309; 282 with a history of TBI and 27 without a history of TBI). Veterans participated in structured clinical interviews regarding psychiatric and TBI histories. Results: Those with a history of TBI met the criteria for significantly more psychiatric diagnoses (p = 0.0003), and were more likely to be at risk for suicide (p = 0.007) than those without a history of TBI. Conclusions: Even among the high-risk cohort of homeless Veterans, those with a history of TBI were found to be at even greater risk for negative psychiatric outcomes. Further research is required to determine if and how the history of TBI contributes to the inability to maintain stable housing. Moreover, the findings highlight both the importance of assessing for history of TBI among this cohort, and educating providers regarding how to address the needs related to injury sequelae.

Listening to Our Patients Learning About Suicide Risk and Protective Factors From Veterans With HIV/AIDS

Purpose: We sought to gather perspectives of veterans with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) regarding suicide risk factors, warning signs, and protective factors. We also aimed to modify an existing Veterans Health Administration tool, the Suicide Risk Assessment Guide Pocket Card, for HIV/AIDS provider use. Methods: Twenty male veterans participated in audio-recorded semistructured interviews that were transcribed and coded for themes. Findings: Veterans highlighted personally relevant psychosocial stressors (i.e., poverty, social isolation and loneliness, and physical health). Although the concept of warning signs did not seem salient to participants, they named indicators of elevated imminent risk for self-directed violence (i.e., “relapse,” “not take’n medications,” and “miss’n appointments”) and few protective factors. No themes emerged regarding recommended pocket card changes. Conclusions: This sample of veterans identified self-directed violence risks noted in the general population and others with HIV/AIDS, as well as proximal events associated with increased risk. Care providers are encouraged to explore the relevance of noted imminent and persistent indicators of increased risk with veterans seeking care.