Painful physical symptoms and antidepressant treatment outcome in depression: a systematic review and meta-analysis.

BACKGROUND: Painful physical symptoms (PPS) are highly prevalent in patients with major depressive disorder (MDD). Presence of PPS in depressed patients are potentially associated with poorer antidepressant treatment outcome. We aimed to evaluate the association of baseline pain levels and antidepressant treatment outcomes. METHODS: We searched PubMed, Embase and Cochrane Library databases from inception through February 2023 based on a pre-registered protocol (PROSPERO: CRD42022381349). We included original studies that reported pretreatment pain measures in antidepressant treatment responder/remitter and non-responder/non-remitter among patients with MDD. Data extraction and quality assessment were performed following the Preferred Reporting Items for Systematic Reviews and Meta-analyses by two reviewers independently. The primary outcome was the difference of the pretreatment pain levels between antidepressant treatment responder/remitter and non-responder/non-remitter. Random-effects meta-analysis was used to calculate effect sizes (Hedge's g) and subgroup and meta-regression analyses were used to explore sources of heterogeneity. RESULTS: A total of 20 studies were included. Six studies reported significantly higher baseline pain severity levels in MDD treatment non-responders (Hedge's g = 0.32; 95% CI, 0.13-0.51; P = 0.0008). Six studies reported the presence of PPS (measured using a pain severity scale) was significantly associated with poor treatment response (OR = 1.46; 95% CI, 1.04-2.04; P = 0.028). Five studies reported significant higher baseline pain interference levels in non-responders (Hedge's g = 0.46; 95% CI, 0.32-0.61; P < 0.0001). Four studies found significantly higher baseline pain severity levels in non-remitters (Hedge's g = 0.27; 95% CI, 0.14-0.40; P < 0.0001). Eight studies reported the presence of PPS significantly associated with treatment non-remission (OR = 1.70; 95% CI, 1.24-2.32; P = 0.0009). CONCLUSIONS: This study suggests that PPS are negatively associated with the antidepressant treatment outcome in patients with MDD. It is possible that better management in pain conditions when treating depression can benefit the therapeutic effects of antidepressant medication in depressed patients.

Omega-3 fatty acids for inflamed depression - A match/mismatch study.

Despite decades of research on the pathophysiology of depression, the development of new therapeutic interventions has been slow, and no biomarkers of treatment response have been clinically implemented. Several lines of evidence suggest that the clinical and biological heterogeneity among patients with major depressive disorder (MDD) has hampered progress in this field. MDD with low-grade inflammation - "inflamed depression" - is a subtype of depression that may be associated with a superior antidepressant treatment response to anti-inflammatory compounds. Omega-3 fatty acid eicosapentaenoic acid (EPA) has anti-inflammatory properties, and preliminary data suggest that it may be particularly efficacious in inflamed depression. In this study we tested the hypothesis that add-on EPA has greater antidepressant efficacy in MDD patients with high baseline high-sensitivity C-reactive protein (hs-CRP) compared to MDD patients with low hs-CRP. All subjects received 2.2 g EPA, 400 mg docosahexaenoic acid and 800 mg of other fatty acids daily for 8 weeks, added to stable ongoing antidepressant treatment. The primary outcome was change in the 17-item Hamilton Depression Rating Scale (HAMD-17). Patients and raters were blind to baseline hs-CRP status. In an intention-to-treat analysis including all subjects with at least one post baseline visit (n = 101), ahs-CRPcut-off of ≥1 mg/L, but not ≥3 mg/L, was associated with a greater improvement in HAMD-17 total score. In addition to a general antidepressant effect among patients with hs-CRP ≥ 1 mg/L, adjuvant EPA treatment improved symptoms putatively related to inflamed depression such as fatigue and sleep difficulties. This adds to the mounting evidence that delineation of MDD subgroups based on inflammation may be clinically relevant to predict treatment response to anti-inflammatory interventions.

Integrated analysis of proteomics, epigenomics and metabolomics data revealed divergent pathway activation patterns in the recent versus chronic post-traumatic stress disorder.

Metabolomics, proteomics and DNA methylome assays, when done in tandem from the same blood sample and analyzed together, offer an opportunity to evaluate the molecular basis of post-traumatic stress disorder (PTSD) course and pathogenesis. We performed separate metabolomics, proteomics, and DNA methylome assays on blood samples from two well-characterized cohorts of 159 active duty male participants with relatively recent onset PTSD (<1.5 years) and 300 male veterans with chronic PTSD (>7 years). Analyses of the multi-omics datasets from these two independent cohorts were used to identify convergent and distinct molecular profiles that might constitute potential signatures of severity and progression of PTSD and its comorbid conditions. Molecular signatures indicative of homeostatic processes such as signaling and metabolic pathways involved in cellular remodeling, neurogenesis, molecular safeguards against oxidative stress, metabolism of polyunsaturated fatty acids, regulation of normal immune response, post-transcriptional regulation, cellular maintenance and markers of longevity were significantly activated in the active duty participants with recent PTSD. In contrast, we observed significantly altered multimodal molecular signatures associated with chronic inflammation, neurodegeneration, cardiovascular and metabolic disorders, and cellular attritions in the veterans with chronic PTSD. Activation status of signaling and metabolic pathways at the early and late timepoints of PTSD demonstrated the differential molecular changes related to homeostatic processes at its recent and multi-system syndromes at its chronic phase. Molecular alterations in the recent PTSD seem to indicate some sort of recalibration or compensatory response, possibly directed in mitigating the pathological trajectory of the disorder.

An immunogenomic phenotype predicting behavioral treatment response: Toward precision psychiatry for mothers and children with trauma exposure.

Inflammatory pathways predict antidepressant treatment non-response among individuals with major depression; yet, this phenomenon may have broader transdiagnostic and transtherapeutic relevance. Among trauma-exposed mothers (Mage = 32 years) and their young children (Mage = 4 years), we tested whether genomic and proteomic biomarkers of pro-inflammatory imbalance prospectively predicted treatment response (PTSD and depression) to an empirically-supported behavioral treatment. Forty-three mother-child dyads without chronic disease completed Child Parent Psychotherapy (CPP) for roughly 9 months. Maternal blood was drawn pre-treatment, CD14 + monocytes isolated, gene expression derived from RNA sequencing (n = 34; Illumina HiSeq 4000;TruSeqcDNA library), and serum assayed (n = 43) for C-Reactive Protein (CRP) and interleukin-1ß (IL-1ß). Symptoms of PTSD and depression decreased significantly from pre- to post-treatment for both mothers and children (all p's < 0.01). Nonetheless, a higher pre-treatment maternal pro-inflammatory imbalance of M1-like versus M2-like macrophage-associated RNA expression (M1/M2) (ß = 0.476, p = .004) and IL-1ß (ß=0.333, p = .029), but not CRP, predicted lesser improvements in maternal PTSD symptoms, unadjusted and adjusting for maternal age, BMI, ethnicity, antidepressant use, income, education, and US birth. Only higher pre-treatment M1/M2 predicted a clinically-relevant threshold of PTSD non-response among mothers (OR = 3.364, p = .015; ROC-AUC = 0.78). Additionally, higher M1/M2 predicted lesser decline in maternal depressive symptoms (ß = 0.556, p = .001), though not independent of PTSD symptoms. For child outcomes, higher maternal IL-1ß significantly predicted poorer PTSD and depression symptom trajectories (ß's = 0.318-0.429, p's < 0.01), while M1/M2 and CRP were marginally associated with poorer PTSD symptom improvement (ß's = 0.295-0.333, p's < 0.056). Pre-treatment pro-inflammatory imbalance prospectively predicts poorer transdiagnostic symptom response to an empirically-supported behavioral treatment for trauma-exposed women and their young children.

Abnormal levels of mitochondrial proteins in plasma neuronal extracellular vesicles in major depressive disorder.

To characterize neuronal mitochondrial abnormalities in major depressive disorder (MDD), functional mitochondrial proteins (MPs) extracted from enriched plasma neuron-derived extracellular vesicles (NDEVs) of MDD participants (n = 20) were quantified before and after eight weeks of treatment with a selective serotonin reuptake inhibitor (SSRI). Pretreatment baseline NDEV levels of the transcriptional type 2 nuclear respiratory factor (NRF2) which controls mitochondrial biogenesis and many anti-oxidant gene responses, regulators of diverse neuronal mitochondrial functions cyclophilin D (CYPD) and mitofusin-2 (MFN2), leucine zipper EF-hand containing transmembrane 1 protein (LETM1) component of a calcium channel/calcium channel enhancer, mitochondrial tethering proteins syntaphilin (SNPH) and myosin VI (MY06), inner membrane electron transport complexes I (subunit 6) and III (subunit 10), the penultimate enzyme of nicotinamide adenine dinucleotide (NAD) generation nicotinamide mononucleotide adenylytransferase 2 (NMNAT2), and neuronal mitochondrial metabolic regulatory and protective factors humanin and mitochondrial open-reading frame of the 12S rRNA-c (MOTS-c) all were significantly lower than those of NDEVs from matched controls (n = 10), whereas those of pro-neurodegenerative NADase Sterile Alpha and TIR motif-containing protein 1 (SARM1) were higher. The baseline NDEV levels of transcription factor A mitochondrial (TFAM) and the transcriptional master-regulator of mitochondrial biogenesis PPAR γ coactivator-1α (PGC-1α) showed no differences between MDD participants and controls. Several of these potential biomarker proteins showed substantially different changes in untreated MDD than those we reported in untreated first-episode psychosis. NDEV levels of MPs of all functional classes, except complex I-6, NRF2 and PGC-1α were normalized in MDD participants who responded to SSRI therapy (n = 10) but not in those who failed to respond (n = 10) by psychiatric evaluation. If larger studies validate NDEV MP abnormalities, they may become useful biomarkers and identify new drug targets.

Epigenetic biotypes of post-traumatic stress disorder in war-zone exposed veteran and active duty males.

Post-traumatic stress disorder (PTSD) is a heterogeneous condition evidenced by the absence of objective physiological measurements applicable to all who meet the criteria for the disorder as well as divergent responses to treatments. This study capitalized on biological diversity observed within the PTSD group observed following epigenome-wide analysis of a well-characterized Discovery cohort (N = 166) consisting of 83 male combat exposed veterans with PTSD, and 83 combat veterans without PTSD in order to identify patterns that might distinguish subtypes. Computational analysis of DNA methylation (DNAm) profiles identified two PTSD biotypes within the PTSD+ group, G1 and G2, associated with 34 clinical features that are associated with PTSD and PTSD comorbidities. The G2 biotype was associated with an increased PTSD risk and had higher polygenic risk scores and a greater methylation compared to the G1 biotype and healthy controls. The findings were validated at a 3-year follow-up (N = 59) of the same individuals as well as in two independent, veteran cohorts (N = 54 and N = 38), and an active duty cohort (N = 133). In some cases, for example Dopamine-PKA-CREB and GABA-PKC-CREB signaling pathways, the biotypes were oppositely dysregulated, suggesting that the biotypes were not simply a function of a dimensional relationship with symptom severity, but may represent distinct biological risk profiles underpinning PTSD. The identification of two novel distinct epigenetic biotypes for PTSD may have future utility in understanding biological and clinical heterogeneity in PTSD and potential applications in risk assessment for active duty military personnel under non-clinician-administered settings, and improvement of PTSD diagnostic markers.

Pre-deployment risk factors for PTSD in active-duty personnel deployed to Afghanistan: a machine-learning approach for analyzing multivariate predictors.

Active-duty Army personnel can be exposed to traumatic warzone events and are at increased risk for developing post-traumatic stress disorder (PTSD) compared with the general population. PTSD is associated with high individual and societal costs, but identification of predictive markers to determine deployment readiness and risk mitigation strategies is not well understood. This prospective longitudinal naturalistic cohort study-the Fort Campbell Cohort study-examined the value of using a large multidimensional dataset collected from soldiers prior to deployment to Afghanistan for predicting post-deployment PTSD status. The dataset consisted of polygenic, epigenetic, metabolomic, endocrine, inflammatory and routine clinical lab markers, computerized neurocognitive testing, and symptom self-reports. The analysis was computed on active-duty Army personnel (N = 473) of the 101st Airborne at Fort Campbell, Kentucky. Machine-learning models predicted provisional PTSD diagnosis 90-180 days post deployment (random forest: AUC = 0.78, 95% CI = 0.67-0.89, sensitivity = 0.78, specificity = 0.71; SVM: AUC = 0.88, 95% CI = 0.78-0.98, sensitivity = 0.89, specificity = 0.79) and longitudinal PTSD symptom trajectories identified with latent growth mixture modeling (random forest: AUC = 0.85, 95% CI = 0.75-0.96, sensitivity = 0.88, specificity = 0.69; SVM: AUC = 0.87, 95% CI = 0.79-0.96, sensitivity = 0.80, specificity = 0.85). Among the highest-ranked predictive features were pre-deployment sleep quality, anxiety, depression, sustained attention, and cognitive flexibility. Blood-based biomarkers including metabolites, epigenomic, immune, inflammatory, and liver function markers complemented the most important predictors. The clinical prediction of post-deployment symptom trajectories and provisional PTSD diagnosis based on pre-deployment data achieved high discriminatory power. The predictive models may be used to determine deployment readiness and to determine novel pre-deployment interventions to mitigate the risk for deployment-related PTSD.

A DNA methylation clock associated with age-related illnesses and mortality is accelerated in men with combat PTSD.

DNA methylation patterns at specific cytosine-phosphate-guanine (CpG) sites predictably change with age and can be used to derive "epigenetic age", an indicator of biological age, as opposed to merely chronological age. A relatively new estimator, called "DNAm GrimAge", is notable for its superior predictive ability in older populations regarding numerous age-related metrics like time-to-death, time-to-coronary heart disease, and time-to-cancer. PTSD is associated with premature mortality and frequently has comorbid physical illnesses suggestive of accelerated biological aging. This is the first study to assess DNAm GrimAge in PTSD patients. We investigated the acceleration of GrimAge relative to chronological age, denoted "AgeAccelGrim" in combat trauma-exposed male veterans with and without PTSD using cross-sectional and longitudinal data from two independent well-characterized veteran cohorts. In both cohorts, AgeAccelGrim was significantly higher in the PTSD group compared to the control group (N = 162, 1.26 vs -0.57, p = 0.001 and N = 53, 0.93 vs -1.60 Years, p = 0.008), suggesting accelerated biological aging in both cohorts with PTSD. In 3-year follow-up study of individuals initially diagnosed with PTSD (N = 26), changes in PTSD symptom severity were correlated with AgeAccelGrim changes (r = 0.39, p = 0.049). In addition, the loss of CD28 cell surface markers on CD8 + T cells, an indicator of T-cell senescence/exhaustion that is associated with biological aging, was positively correlated with AgeAccelGrim, suggesting an immunological contribution to the accelerated biological aging. Overall, our findings delineate cellular correlates of biological aging in combat-related PTSD, which may help explain the increased medical morbidity and mortality seen in this disease.

The Genetic Basis for the Increased Prevalence of Metabolic Syndrome among Post-Traumatic Stress Disorder Patients.

Post-traumatic stress disorder (PTSD) is a highly debilitating psychiatric disorder that can be triggered by exposure to extreme trauma. Even if PTSD is primarily a psychiatric condition, it is also characterized by adverse somatic comorbidities. One illness commonly co-occurring with PTSD is Metabolic syndrome (MetS), which is defined by a set of health risk/resilience factors including obesity, elevated blood pressure, lower high-density lipoprotein cholesterol, higher low-density lipoprotein cholesterol, higher triglycerides, higher fasting blood glucose and insulin resistance. Here, phenotypic association between PTSD and components of MetS are tested on a military veteran cohort comprising chronic PTSD presentation (n = 310, 47% cases, 83% male). Consistent with previous observations, we found significant phenotypic correlation between the various components of MetS and PTSD severity scores. To examine if this observed symptom correlations stem from a shared genetic background, we conducted genetic correlation analysis using summary statistics data from large-scale genetic studies. Our results show robust positive genetic correlation between PTSD and MetS (rg[SE] = 0.33 [0.056], p = 4.74E-09), and obesity-related components of MetS (rg = 0.25, SE = 0.05, p = 6.4E-08). Prioritizing genomic regions with larger local genetic correlation implicate three significant loci. Overall, these findings show significant genetic overlap between PTSD and MetS, which may in part account for the markedly increased occurrence of MetS among PTSD patients.

Pre-treatment allostatic load and metabolic dysregulation predict SSRI response in major depressive disorder: a preliminary report.

BACKGROUND: Major depressive disorder (MDD) is associated with increased allostatic load (AL; a measure of physiological costs of repeated/chronic stress-responding) and metabolic dysregulation (MetD; a measure of metabolic health and precursor to many medical illnesses). Though AL and MetD are associated with poor somatic health outcomes, little is known regarding their relationship with antidepressant-treatment outcomes. METHODS: We determined pre-treatment AL and MetD in 67 healthy controls and 34 unmedicated, medically healthy MDD subjects. Following this, MDD subjects completed 8-weeks of open-label selective serotonin reuptake inhibitor (SSRI) antidepressant treatment and were categorized as 'Responders' (⩾50% improvement in depression severity ratings) or 'Non-responders' (<50% improvement). Logistic and linear regressions were performed to determine if pre-treatment AL or MetD scores predicted SSRI-response. Secondary analyses examined cross-sectional differences between MDD and control groups. RESULTS: Pre-treatment AL and MetD scores significantly predicted continuous antidepressant response (i.e. absolute decreases in depression severity ratings) (p = 0.012 and 0.014, respectively), as well as post-treatment status as a Responder or Non-responder (p = 0.022 and 0.040, respectively), such that higher pre-treatment AL and MetD were associated with poorer SSRI-treatment outcomes. Pre-treatment AL and MetD of Responders were similar to Controls, while those of Non-responders were significantly higher than both Responders (p = 0.025 and 0.033, respectively) and Controls (p = 0.039 and 0.001, respectively). CONCLUSIONS: These preliminary findings suggest that indices of metabolic and hypothalamic-pituitary-adrenal-axis dysregulation are associated with poorer SSRI-treatment response. To our knowledge, this is the first study to demonstrate that these markers of medical disease risk also predict poorer antidepressant outcomes.

Multi-omic biomarker identification and validation for diagnosing warzone-related post-traumatic stress disorder.

Post-traumatic stress disorder (PTSD) impacts many veterans and active duty soldiers, but diagnosis can be problematic due to biases in self-disclosure of symptoms, stigma within military populations, and limitations identifying those at risk. Prior studies suggest that PTSD may be a systemic illness, affecting not just the brain, but the entire body. Therefore, disease signals likely span multiple biological domains, including genes, proteins, cells, tissues, and organism-level physiological changes. Identification of these signals could aid in diagnostics, treatment decision-making, and risk evaluation. In the search for PTSD diagnostic biomarkers, we ascertained over one million molecular, cellular, physiological, and clinical features from three cohorts of male veterans. In a discovery cohort of 83 warzone-related PTSD cases and 82 warzone-exposed controls, we identified a set of 343 candidate biomarkers. These candidate biomarkers were selected from an integrated approach using (1) data-driven methods, including Support Vector Machine with Recursive Feature Elimination and other standard or published methodologies, and (2) hypothesis-driven approaches, using previous genetic studies for polygenic risk, or other PTSD-related literature. After reassessment of ~30% of these participants, we refined this set of markers from 343 to 28, based on their performance and ability to track changes in phenotype over time. The final diagnostic panel of 28 features was validated in an independent cohort (26 cases, 26 controls) with good performance (AUC = 0.80, 81% accuracy, 85% sensitivity, and 77% specificity). The identification and validation of this diverse diagnostic panel represents a powerful and novel approach to improve accuracy and reduce bias in diagnosing combat-related PTSD.

Association of comorbid depression with inpatient outcomes in critical limb ischemia.

There is a growing body of evidence that peripheral artery disease (PAD) may be impacted by depression. The objective of this study is to determine whether outcomes, primarily major amputation, differ between patients with depression and those without who presented to hospitals with critical limb ischemia (CLI), the end-stage of PAD. A retrospective cohort of patients hospitalized for CLI during 2012 and 2013 was identified from the National Inpatient Sample (NIS) using ICD-9 codes. The primary outcome was major amputation and secondary outcomes were length of stay and other complications. The sample included 116,008 patients hospitalized for CLI, of whom 10,512 (9.1%) had comorbid depression. Patients with depression were younger (64 ± 14 vs 67 ± 14 years, p < 0.001) and more likely to be female (55% vs 41%, p < 0.001), white (73% vs 66%, p < 0.001), and tobacco users (46% vs 41%, p < 0.001). They were also more likely to have prior amputations (9.8% vs 7.9%, p < 0.001). During the hospitalization, the rate of major amputation was higher in patients with comorbid depression (11.5% vs 9.1%, p < 0.001). In multivariable analysis, excluding patients who died prior to/without receiving an amputation (n = 2621), comorbid depression was associated with a 39% increased odds of major amputation (adjusted OR 1.39, 95% CI 1.30, 1.49; p < 0.001). Across the entire sample, comorbid depression was also independently associated with a slightly longer length of stay (ß = 0.199, 95% CI 0.155, 0.244; p < 0.001). These results provide further evidence that depression is a variable of interest in PAD and surgical quality databases should include mental health variables to enable further study.

Mechanistic inferences on metabolic dysfunction in posttraumatic stress disorder from an integrated model and multiomic analysis: role of glucocorticoid receptor sensitivity.

Posttraumatic stress disorder (PTSD) is associated with neuroendocrine alterations and metabolic abnormalities; however, how metabolism is affected by neuroendocrine disturbances is unclear. The data from combat-exposed veterans with PTSD show increased glycolysis to lactate flux, reduced TCA cycle flux, impaired amino acid and lipid metabolism, insulin resistance, inflammation, and hypersensitive hypothalamic-pituitary-adrenal (HPA) axis. To analyze whether the co-occurrence of multiple metabolic abnormalities is independent or arises from an underlying regulatory defect, we employed a systems biological approach using an integrated mathematical model and multiomic analysis. The models for hepatic metabolism, HPA axis, inflammation, and regulatory signaling were integrated to perform metabolic control analysis (MCA) with respect to the observations from our clinical data. We combined the metabolomics, neuroendocrine, clinical laboratory, and cytokine data from combat-exposed veterans with and without PTSD to characterize the differences in regulatory effects. MCA revealed mechanistic association of the HPA axis and inflammation with metabolic dysfunction consistent with PTSD. This was supported by the data using correlational and causal analysis that revealed significant associations between cortisol suppression, high-sensitivity C-reactive protein, homeostatic model assessment of insulin resistance, γ-glutamyltransferase, hypoxanthine, and several metabolites. Causal mediation analysis indicates that the effects of enhanced glucocorticoid receptor sensitivity (GRS) on glycolytic pathway, gluconeogenic and branched-chain amino acids, triglycerides, and hepatic function are jointly mediated by inflammation, insulin resistance, oxidative stress, and energy deficit. Our analysis suggests that the interventions to normalize GRS and inflammation may help to manage features of metabolic dysfunction in PTSD.

The association of comorbid depression with mortality and amputation in veterans with peripheral artery disease.

OBJECTIVE: Peripheral artery disease (PAD) is an increasing health concern with rising incidence globally. Previous studies have shown an association between PAD incidence and depression. The objective of the study was to determine the association of comorbid depression with PAD outcomes (amputation and all-cause mortality rates) in veterans. METHODS: An observational retrospective cohort of 155,647 patients with incident PAD (2003-2014) from nationwide U.S. Veterans Health Administration hospitals was conducted using the national Veterans Affairs Corporate Data Warehouse. Depression was measured using concurrent International Classification of Diseases, Ninth Revision diagnosis codes 6 months before or after PAD diagnosis. The main outcomes were incident major amputation and all-cause mortality. Crude associations were assessed with Kaplan-Meier plots. The effects of depression adjusted for covariates were analyzed using Cox proportional hazards models. RESULTS: Depression was present in 16% of the cohort, with the occurrence of 9517 amputations and 63,287 deaths (median follow-up, 5.9 years). Unadjusted hazard ratios (HRs) of comorbid depression for amputations and all-cause mortality were 1.32 (95% confidence interval [CI], 1.25-1.39) and 1.02 (95% CI, 0.99-1.04), respectively. After adjustment for covariates in Cox regression models, a diagnosis of comorbid depression at the time of PAD diagnosis was associated with a 13% higher amputation (HR, 1.13; 95% CI, 1.07-1.19) and 17% higher mortality (HR, 1.17; 95% CI, 1.14-1.20) risk compared with patients with no depression. On stratification by use of antidepressants, depressed patients not taking antidepressants had a 42% higher risk of amputation (HR, 1.42; 95% CI, 1.27-1.58) compared with those without depression. Patients taking antidepressants for depression still had increased risk of amputation but only 10% higher compared with those without depression (HR, 1.10; 95% CI, 1.03-1.17). Interestingly, patients taking antidepressants for other indications also had a higher risk of amputation compared with those not having depression or not taking antidepressants (HR, 1.08; 95% CI, 1.03-1.14). Having any diagnosis of depression or the need for antidepressants increased the mortality risk by 18% to 25% in the PAD cohort compared with those without depression and not taking antidepressants for any other indication. CONCLUSIONS: PAD patients with comorbid depression have a significantly higher risk of amputation and mortality than PAD patients without depression. Furthermore, untreated depression was associated with an increased amputation risk in the PAD population, more so than depression or other mental illness being treated by antidepressants. The underlying mechanisms for causality, if any, remain to be determined. The association of antidepressant treatment use with amputation risk should prompt further investigations into possible mechanistic links between untreated depression and vascular dysfunction.

Depression severity is associated with increased inflammation in veterans with peripheral artery disease.

The present study examines the association between depressive symptoms and inflammatory markers in peripheral artery disease (PAD) to better understand the mechanistic relationship between depression and PAD. A cross-sectional sample of 117 patients with PAD (97% male, 76% Caucasian) was recruited from the San Francisco Veterans Affairs Medical Center. Patients were categorized into three subgroups based upon current depressive symptom severity, as defined by Patient Health Questionnaire-8 scores: no symptoms (score of 0-4, n = 62), mild symptoms (score of 5-9, n = 33), and moderate/severe symptoms (score ≥ 10, n = 22). Serum levels of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), soluble intercellular adhesion molecule-1 (ICAM-1), and tumor necrosis factor-alpha (TNF-α) were assayed and log-transformed for multivariable analysis. To decrease the possibility of Type 1 errors, inflammatory markers were standardized and summed to create a total inflammatory score. In a multivariable analysis controlling for demographics, PAD severity, and atherosclerotic risk factors, mild and moderate/severe depressive symptoms were predictive of a higher total inflammatory score when compared to the group with no symptoms (mild symptoms p = 0.04, moderate/severe symptoms p = 0.007). Exploratory multivariable analyses of individual inflammatory markers found IL-6 levels were significantly higher in the moderate/severe symptoms group ( p = 0.006) than in the no symptoms group. Moreover, hs-CRP and ICAM-1 trended upwards with increasing depression severity. TNF-α was not associated with depression severity. We conclude that depressive symptom severity was independently associated with greater inflammation in PAD. Future research should examine the strength and directionality of this association through larger prospective cohort studies, as well as investigate the pathophysiological mechanisms responsible.

Increased pro-inflammatory milieu in combat related PTSD - A new cohort replication study.

INTRODUCTION: Several lines of evidence indicate that increased inflammation is associated with Post-Traumatic Stress Disorder (PTSD). We have previously reported that peripheral inflammatory markers are significantly higher in combat-exposed veterans with than without PTSD. This study was designed to replicate these findings in a new study cohort using the same population and recruitment strategies. METHODS: Sixty-one male war veterans (31 PTSD and 30 control subjects) were included in this replication study. Levels of Interleukin-6, Tumor Necrosis Factor-alpha, Gamma interferon, and high-sensitivity C-reactive protein were quantified in blood samples. A standardized "total pro-inflammatory score" was calculated to limit the number of statistical comparisons. The Clinician Administered PTSD Scale (CAPS) rating scale was used to assess PTSD symptom severity. RESULTS: PTSD subjects had significantly higher total pro-inflammatory scores compared to non-PTSD subjects in unadjusted analysis (Cohen's d=0.75, p=0.005) as well as after adjusting for potentially confounding effects of age, BMI, smoking, and potentially interfering medications and somatic co-morbidities (p=0.023). There were no significant correlations between inflammatory markers and severity of symptoms within the PTSD group. CONCLUSIONS: We replicated, in a new sample, our previous finding of increased inflammatory markers in combat-exposed PTSD subjects compared to combat-exposed non-PTSD controls. These findings strongly add to the growing literature suggesting that immune activation may be an important aspect of PTSD pathophysiology, although not directly correlated with current PTSD symptom levels in the PTSD group.

The Association Between Psychiatric Disorders and Telomere Length: A Meta-Analysis Involving 14,827 Persons.

OBJECTIVE: This study examined the relationship between leukocyte telomere length (LTL), a marker of cell aging, and psychiatric disorders in adults compared with controls using meta-analytic methods. METHODS: Data were abstracted from studies examining the relationship between LTL and adult psychiatric disorders. In addition to an overall estimate of effect size, subgroup analyses and meta-regression were performed to examine whether covariates (including psychiatric diagnoses) moderated the estimate. RESULTS: A significant overall effect size showing LTL shortening was found across all psychiatric disorders (Hedge g = -0.50, p < .001). Subgroup analyses did not demonstrate significant differences in effect size based on individual covariates (psychiatric disorder, sex, age, or assay method). The meta-regression indicated that although type of disorder and, likely, age moderate the overall effect size, the heterogeneity between studies could not be explained by a model that included these variables as well as sex and assay method. Although not significantly different, posttraumatic stress disorder, anxiety disorders, and depressive disorders had comparatively larger effect sizes (-1.27, -0.53, and -0.55), and psychotic and bipolar disorders had comparatively smaller ones (-0.23 and -0.26). CONCLUSIONS: We observed a robust effect size of LTL shortening for psychiatric disorders as a whole compared with controls. The results were less straightforward regarding relative differences in the strength of this association by specific disorder. Future studies should focus on mechanisms explaining accelerated cell aging with psychiatric illness, defining directions (if any) of causality and elucidating possible differences in this association between disorders.

Global arginine bioavailability, a marker of nitric oxide synthetic capacity, is decreased in PTSD and correlated with symptom severity and markers of inflammation.

INTRODUCTION: Psychiatric, physical and biological aspects of posttraumatic stress disorder (PTSD) may be associated with dysfunctions in several cellular processes including nitric oxide (NO) production. NO is synthesized from arginine in a reaction carried out by NO synthase (NOS) enzymes. The recently introduced "global arginine bioavailability ratio" (GABR; ratio of arginine to [ornithine+citrulline]) has been proposed as a reliable approximation of NO synthetic capacity in vivo. The objectives of the present study were to test the hypotheses that (i) subjects with combat-related PTSD have lower GABR scores than combat controls, (ii) GABR score is inversely associated with the severity of psychopathological measures, (iii) GABR score is inversely associated with markers of inflammation. METHODS: Metabolic profiling for plasma samples (i.e. arginine, citrulline and ornithine) and inflammation markers (interleukin [IL]-6, IL-1ß, tumor necrosis factor [TNF]-α, interferon [IFN]-γ and C-reactive protein [CRP]) were assessed in 56 combat-exposed males with PTSD and 65 combat-exposed males without PTSD. We assessed severity of PTSD (Clinician Administered PTSD Scale [CAPS]) and depression (Beck Depression Inventory-II [BDI-II]) as well as history of early life trauma (Early Trauma Inventory [ETI]) and affectivity (Positive and Negative Affect Schedule [PANAS]). RESULTS: The GABR value was (i) significantly lower in PTSD subjects compared to controls (p=0.001), (ii) significantly inversely correlated with markers of inflammation including IL6 (p=0.04) and TNFα (p=0.02), and (iii) significantly inversely correlated with CAPS current (p=0.001) and lifetime (p<0.001) subscales, ETI (p=0.045) and PANAS negative (p=0.006). Adding antidepressant use or MDD diagnosis as covariates led to similar results. Adding age and BMI as covariates also led to similar results, with the exception of IL6 and ETI losing their significant association with GABR. DISCUSSION: This study provides the first evidence that global arginine bioavailability, a marker of NO synthetic capacity in vivo, is lower in veterans with PTSD and is negatively associated with some markers of inflammation as well as with measures of PTSD symptom severity, negative affectivity and childhood adverse experiences. These findings add to the accumulating evidence that specific cellular dysfunction may be associated with the symptomatology of PTSD and may help to explain the higher burden of cardio-metabolic disturbances seen in this disorder.

A population of atypical CD56(-)CD16(+) natural killer cells is expanded in PTSD and is associated with symptom severity.

INTRODUCTION: Post-traumatic stress disorder (PTSD) has been associated with immune disturbances, including a higher incidence of infections and autoimmune diseases as well as a net pro-inflammatory state. Natural killer (NK) cells, a key component of the innate immune system, have been less well-studied in PTSD despite their importance in immunity. METHODS: We studied two independent samples of combat-exposed male war veterans with or without PTSD, the first ("Discovery Sample") to generate hypotheses, and the second ("Validation Sample") to replicate the findings. The Discovery Sample was comprised of 42 PTSD subjects and 42 controls. The Validation Sample was comprised of 25 PTSD subjects and 30 controls. Participants had fasting, morning blood samples collected for examination of the frequency of NK cell subsets, determined by flow cytometry. The current and lifetime Clinician Administered PTSD Scale (CAPS) was used to assess symptom severity. Statistical analyses were adjusted for age and BMI. RESULTS: PTSD subjects compared to controls had (i) a significantly higher relative frequency of atypical CD56(-)CD16(+) NK cells in the Discovery Sample (p=0.027), which was replicated in the Validation Sample (p=0.004) and the combined sample (p<0.001), and (ii) a non-significantly lower relative frequency of CD56(bright)CD16(-) NK cells in the two samples (p=0.082; p=0.118), which became statistically significant in the combined sample (p=0.020). Further, within subjects with PTSD of both samples, the relative frequency of atypical CD56(-)CD16(+) NK cells was near significantly positively correlated with lifetime PTSD severity (p=0.074). DISCUSSION: This study is the first to characterize NK cell subsets in individuals with PTSD. The results suggest that combat-exposed men with PTSD exhibit an aberrant profile of NK cells with significantly higher frequencies of an atypical population of CD56(-)CD16(+) cells and possibly lower frequencies of the functional CD56(bright)CD16(-) NK cell subsets. Higher proportions of dysfunctional CD56(-)CD16(+) cells have been reported in certain chronic viral infections and in senescent individuals. It is possible that this could contribute to immune dysfunctions and prematurely senescent phenotypes seen in PTSD.