Elevated C-reactive protein levels in schizophrenia inpatients is associated with aggressive behavior

Relationship between plasma TNF-α levels and agitation symptoms in first episode patients with schizophrenia

BACKGROUND

Increasing evidence suggested that immune abnormalities involved in the pathophysiology of schizophrenia. However, the relationship between immunity and clinical features has not been clarified. The aim of this study was to measure the plasma levels of tumor necrosis factor alpha (TNF-α) and soluble TNF-α receptor 1 (sTNF-α R1) and to investigate their association with agitation in first episode patients with schizophrenia (FEPS).

METHODS

The plasma TNF-α and sTNF-α R1 levels were measured using sandwich enzyme-linked immunosorbent assay (ELISA) in the FEPS with (n = 36) and without agitation (n = 49) symptoms, and healthy controls (HCs, n = 54). The psychopathology was assessed by the Positive and Negative Syndrome Scale (PANSS), and the agitation symptoms were evaluated by the PANSS excitatory component (PANSS-EC).

RESULTS

The plasma TNF-α levels in patients with and without agitation symptoms were significantly higher than those in HCs. The patients with agitation had significantly higher plasma TNF-α levels compared to the patients without agitation. There were no significant differences in the sTNF-α R1 levels among the three groups. Furthermore, the plasma TNF-α levels were positively correlated with the PANSS total score, Positive and General psychopathological subscores, and PANSS-EC score in the FEPS, but the relationships were not found for the plasma sTNF-α R1 levels.

CONCLUSIONS

These results suggested that TNF-α might play an important role in the onset and development of agitation symptoms of schizophrenia.

White blood cells and patients with psychiatric disorders needing seclusion: A retrospective non-interventional study

OBJECTIVE

The objective of this retrospective study was to investigate the peripheral immunological markers using leucocyte count, the neutrophil to lymphocyte ratio (NLR), the platelet to lymphocyte ratio (PLR), and the monocyte to lymphocyte ratio (MLR) in patients with aggressive behavior, during and after seclusion.

METHODS

Ninety-nine inpatients were included in this retrospective study. Leucocyte count was measured, and NLR, PLR and MLR were calculated and compared between a group of patients who required seclusion and a group who did not. A multivariate analysis was performed using binary logistic regression, including confounding factors such as age, gender, medication, BMI, smoking status and diagnosis.

RESULTS

We found the lowest levels of lymphocytes (P=0.01) and basophils (P<0.01) and the highest NLR (P=0.02) and MLR (P=0.04) in the seclusion group. We also found a restoration of these parameters after the end of the seclusion period. Furthermore, we found a positive correlation between the PANSS negative subscore, and PLR (P=0.05), or MLR (P=0.03) after seclusion, and between the MLR variation across the seclusion period and the PANSS general subscore after the end of seclusion (P=0.04).

CONCLUSION

This study shows that NLR and MPR are higher in patients with aggressive symptoms and/or agitation who require seclusion. These immunological markers could be considered as state markers.

Nutritional Criminology: Why the Emerging Research on Ultra-Processed Food Matters to Health and Justice

There is mounting concern over the potential harms associated with ultra-processed foods, including poor mental health and antisocial behavior. Cutting-edge research provides an enhanced understanding of biophysiological mechanisms, including microbiome pathways, and invites a historical reexamination of earlier work that investigated the relationship between nutrition and criminal behavior. Here, in this perspective article, we explore how this emergent research casts new light and greater significance on previous key observations. Despite expanding interest in the field dubbed 'nutritional psychiatry', there has been relatively little attention paid to its relevancy within criminology and the criminal justice system. Since public health practitioners, allied mental health professionals, and policymakers play key roles throughout criminal justice systems, a holistic perspective on both historical and emergent research is critical. While there are many questions to be resolved, the available evidence suggests that nutrition might be an underappreciated factor in prevention and treatment along the criminal justice spectrum. The intersection of nutrition and biopsychosocial health requires transdisciplinary discussions of power structures, industry influence, and marketing issues associated with widespread food and social inequalities. Some of these discussions are already occurring under the banner of 'food crime'. Given the vast societal implications, it is our contention that the subject of nutrition in the multidisciplinary field of criminology-referred to here as nutritional criminology-deserves increased scrutiny. Through combining historical findings and cutting-edge research, we aim to increase awareness of this topic among the broad readership of the journal, with the hopes of generating new hypotheses and collaborations.

Psychiatric Symptoms, Aggression, and Sexual Dysfunction Among Patients With Benign Anal Conditions

INTRODUCTION

The aim of this study was to investigate the incidence of general psychiatric symptoms, aggression levels, and sexual dysfunction in patients with benign anorectal diseases and compare the results with those of healthy control subjects.

METHODS

We prospectively enrolled consecutive adult patients who presented for treatment of benign perianal diseases and healthy control subjects between June 2017 and December 2018. All patients had either grade 3 or 4 hemorrhoidal disease or perianal fistula with active discharge who had not undergone previous anorectal surgery. We also included a control group with benign subcutaneous lumps presenting for minor surgery. We used the Symptom Checklist-90-Revised Form to evaluate general psychiatric symptoms, the Buss-Perry Aggression Questionnaire (BPAQ) to evaluate aggression levels, and the Arizona Sexual Experiences Scale to evaluate sexual dysfunction.

RESULTS

A total of 563 patients were assessed for eligibility; after exclusions, 94 with anal fistula, 89 with hemorrhoids, and 59 healthy control subjects were enrolled. The groups were similar with regard to age, gender, and educational level. Physical and verbal aggression, anger, and total BPAQ score were significantly higher in patients with perianal fistula than in those with hemorrhoidal disease and healthy control subjects (P < .001).

CONCLUSION

This study suggests that patients with perianal fistula have higher levels of aggression than healthy control subjects and those with hemorrhoidal disease. One must bear this in mind during preoperative patient evaluations and obtaining informed consent. Further studies are needed to investigate the reason for this association and potential causality.

Aggression and its correlation with plasma C-reactive protein levels in patients with schizophrenia: A hospital based cross-sectional study

Background

The correlation between plasma C-reactive protein (CRP) and aggression in schizophrenia has recently become an area of interest. As an acute phase reactant, neuro-immuno-modulatory and neurohumoral functions of CRP might have a role in understanding causation of aggression in disease and this may have implications in therapeutic intervention.

Aims

To assess aggression and plasma CRP in patients with schizophrenia and to compare aggression in patients with normal and elevated CRP.

Methods and Material

A hospital-based cross-sectional study was carried out over a period of one year (2019-2020). Patients of schizophrenia as per International Classification of Diseases 10 were selected. Modified Overt Aggression Scale was applied, and plasma CRP levels were estimated in the selected patients.

Statistical Analysis

Mean aggression scores were compared in patients with normal and elevated CRP. And aggression scores were correlated with plasma CRP levels.

Results

Mean aggression score (22.93 ± 2.80) was significantly (P < .001) higher in patients with elevated CRP. There is a positive correlation (r = 0.855, P < .001) between aggression and plasma CRP.

Conclusion

Patients with elevated CRP were more aggressive compared to the patients with normal CRP.

The association between schizophrenia and white blood cells count: a bidirectional two-sample Mendelian randomization study

BACKGROUND

Positive associations between the risk of schizophrenia and the level of white blood cells (WBC) count have been suggested by observational studies. However, the causality of this association is still unclear.

METHODS

We used a group of bidirectional two-sample Mendelian randomization (MR) analyses to estimate the causal relationship between schizophrenia and WBC count traits (i.e., WBC count, lymphocyte count, neutrophil count, basophil count, eosinophil count, and monocyte count). The threshold of FDR-adjusted P < 0.05 was considered as showing potential evidence of a causal effect. Instrument variables were included based on the genome-wide significance threshold (P < 5 × 10^- 8) and linkage disequilibrium (LD) clumping (r² < 0.01). In total, 81, 95, 85, 87, 76, and 83 schizophrenia-related single nucleotide polymorphisms (SNPs) were used as genetic instruments from Psychiatric Genomics Consortium for six WBC count traits, respectively. And in reverse MR analysis, 458, 206, 408, 468, 473, and 390 variants extracted from six WBC count traits were utilized as genetic instruments, which were obtained from a recent large-scale Genome-Wide Association Study (GWAS).

RESULTS

Genetically predicted schizophrenia was positively associated with the level of WBC count [odds ratio (OR) 1.017, 95% confidence interval (CI) 1.008-1.026; P = 7.53 × 10^- 4], basophil count (OR 1.014, 95%CI 1.005-1.022; P = 0.002), eosinophil count (OR 1.021, 95%CI 1.011-1.031; P = 2.77 × 10^- 4), monocyte count (OR 1.018, 95%CI 1.009-1.027; P = 4.60 × 10^- 4), lymphocyte count (OR 1.021, 95%CI 1.012-1.030; P = 4.51 × 10^- 5), and neutrophil count (OR 1.013, 95%CI 1.005-1.022; P = 0.004). WBC count traits are not associated with the risk of schizophrenia in our reverse MR results.

CONCLUSION

Schizophrenia is associated with elevated levels of WBC count (i.e., higher WBC count, lymphocyte count, neutrophil count, basophil count, eosinophil count, and monocyte count).

The Associations of Neutrophil-Lymphocyte, Platelet-Lymphocyte, Monocyte-Lymphocyte Ratios and Immune-Inflammation Index with Negative Symptoms in Patients with Schizophrenia

Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), monocyte-lymphocyte ratio (MLR) and systemic immune-inflammation index (SII index) are increasingly used as indicators of inflammation in different conditions, including schizophrenia. However, their relationship with negative symptoms, including anhedonia, is largely unknown. Included were 200 patients with schizophrenia and 134 healthy controls (HC), assessed for physical anhedonia (PA), using the Revised Physical Anhedonia Scale (RPAS), and social anhedonia (SA) by the Revised Social Anhedonia Scale (RSAS). Patients were rated by the Positive and Negative Syndrome Scale (PANSS), the Clinical Assessment Interview for Negative Symptoms (CAINS) and the Brief Negative Symptom Scale (BNSS). Most of the negative symptoms were in a weak to moderate positive correlations with blood cell inflammatory ratios, namely, between NLR and MLR with PANSS negative scale, CAINS, and BNSS, and in male patients, between PLR and PANSS negative scale and CAINS. Fewer correlations were detected in females, but also in a positive direction. An exception was SA, given the negative correlation between its severity and the SII index in females, and its presence and higher PLR in males. While different negative symptoms were associated with subclinical inflammation, the relationship between SA and lower inflammatory markers deserves further exploration.

The NLRP3 inflammasome is involved in resident intruder paradigm-induced aggressive behaviors in mice

Background: Aggressive behaviors are one of the most important negative behaviors that seriously endangers human health. Also, the central para-inflammation of microglia triggered by stress can affect neurological function, plasticity, and behavior. NLRP3 integrates stress-related signals and is a key driver of this neural para-inflammation. However, it is unclear whether the NLRP3 inflammasome is implicated in the development of aggressive behaviors. Methods: First, aggressive behavior model mice were established using the resident intruder paradigm. Then, aggressive behaviors were determined with open-field tests (OFT), elevated plus-maze (EPM), and aggressive behavior tests (AT). Moreover, the expression of P2X7R and NLRP3 inflammasome complexes were assessed by immunofluorescence and Western blot. The levels of NLRP3 and inflammatory cytokines were evaluated using enzyme-linked immunosorbent assay (ELISA) kits. Finally, nerve plasticity damage was observed by immunofluorescence, transmission electron microscope, and BrdU staining. Results: Overall, the resident intruder paradigm induced aggressive behaviors, activated the hippocampal P2X7R and NLRP3 inflammasome, and promoted the release of proinflammatory cytokines IL-1β in mice. Moreover, NLRP3 knockdown, administration of P2X7R antagonist (A804598), and IL-1β blocker (IL-1Ra) prevented NLRP3 inflammasome-driven inflammatory responses and ameliorated resident intruder paradigm-induced aggressive behaviors. Also, the resident intruder paradigm promoted the activation of mouse microglia, damaging synapses in the hippocampus, and suppressing hippocampal regeneration in mice. Besides, NLRP3 knockdown, administration of A804598, and IL-1Ra inhibited the activation of microglia, improved synaptic damage, and restored hippocampal regeneration. Conclusion: The NLRP3 inflammasome-driven inflammatory response contributed to resident intruder paradigm-induced aggressive behavior, which might be related to neuroplasticity. Therefore, the NLRP3 inflammasome can be a potential target to treat aggressive behavior-related mental illnesses.

Association between neutrophil to lymphocyte ratio and mood polarity in adolescents admitted to an inpatient psychiatric ward

Inflammatory processes are associated with mood disorders, but data on pediatric patients are scarce. The aim of this study was to investigate a possible association between elevated neutrophil/lymphocyte ratio (NLR) - a marker of inflammation and mood polarity (manic/depressed) in adolescents, admitted between 2010 and 2015 due to a mood disorder episode and to an adolescent inpatient ward. Electronic medical records of 305 patients (aged 10-19 years, 60.6% males) admitted during the study period due to a mood disorder episode were reviewed. Of these, 63 were diagnosed with manic episodes and 242 with depressive episodes. Multivariate analyses were used to compare NLR between and within the two groups, covarying for age, sex, and antipsychotic use. NLR was significantly higher in the manic episode group compared with the depression one. Moreover, in inpatients with multiple hospitalizations, the NLR was higher during their manic episodes than that during their nonmanic states. These results suggest that, as has been reported in adults with bipolar disorder, inflammatory mechanisms may be involved in adolescents' mood disorders as well, particularly in the manic episodes. Thus, clinicians may consider adding anti-inflammatories as part of the treatment of these patients.

Could CRP be a differential biomarker of illness stages in schizophrenia? A systematic review and meta-analysis

BACKGROUND

Patients with schizophrenia display peripheral inflammation but the impact of illness phase is not clear. Our meta-analysis investigated the difference in CRP levels between patients with schizophrenia and controls according to their illness phase.

METHODS

After a systematic search, all studies measuring CRP in patients with schizophrenia and controls were included. Standardized mean differences were calculated between patients and controls according to illness phase. The influence of sociodemographic and clinical variables on our results was investigated using a meta-regression analysis.

RESULTS

Fifty studies were included in this meta-analysis. Patients with schizophrenia had higher CRP levels than controls in the acute (p < 0.00001) and stable (p < 0.00001) stage of their disease. Patients with acute exacerbation of schizophrenia had higher CRP levels than stable patients (p = 0.02) but this difference did not persist when considering antipsychotic-medicated patients in both phases. Meta-regressions found that the increase of CRP in acutely ill patients as compared to controls was influenced by age (p < 0.01), BMI (p = 0.01) and first episode (p = 0.02), whereas the increase in CRP levels of stable patients as compared to controls was moderated by BMI (p = 0.004).

CONCLUSIONS

In conclusion, this meta-analysis provides strong evidence that patients with schizophrenia have higher CRP levels than controls, but also show an increase in inflammatory response in the acute stage of the disease as compared to the stable stage. CRP could thus be considered as a state marker and a trait marker of the disease.

Aggression, Alexithymia and Sense of Coherence in a Sample of Schizophrenic Outpatients

Schizophrenia elevates the risk for aggressive behavior, and there is a need to better understand the associated variables predicting aggression for treatment and prevention purposes. The aim of the present study is to determine the relationship between alexithymia, sense of coherence and aggressive behavior in a sample of schizophrenic outpatients. Using a correlational research design, standardized self-report questionnaires assessed aggression (brief aggression questionnaire—BAQ), alexithymia (Toronto Alexithymia Scale—TAS) and sense of coherence (sense of coherence questionnaire—SOC) in a sample of 100 schizophrenic outpatients in clinical remission. Participants reported high levels of aggression and alexithymia along with reduced sense of coherence. Significant negative correlations were evidenced among scores on the SOC scale (p < 0.001) with both the TAS as well as with the BAQ scales. However, a positive correlation (p < 0.001) was observed between the TAS and BAQ scales. Regression indicated that 27% of the variation in the BAQ rating was explained by the TAS, while an additional 17.8% was explained by the sense of coherence. The difficulty identifying feelings of alexithymia and the comprehensibility and manageability components of sense of coherence significantly predicted anger, hostility and physical aggression. Sense of coherence mediated the relationship between alexithymia and aggression. From the path analysis, comprehensibility emerged as the key factor counterbalancing alexithymic traits and aggressive behaviors, and manageability effectuated higher anger control. The findings hold practical implications for the treatment and rehabilitation of schizophrenic patients.

Exploring the role of serum lipid profile and neutrophil-to-lymphocyte ratio in violent suicide attempters: a cross sectional study

BACKGROUND

Suicidality is one of the most common complications of mental disorders, so that the identification of potential biomarkers may be relevant in clinical practice. To date, the role of serum lipids and neutrophil/lymphocyte ratio (NLR) has been explored albeit with conflicting results. To the best of our knowledge, no study has explored lipid levels concomitantly with NLR in relation to violent suicide attempts. Therefore, we aimed to investigate whether serum lipid levels and NLR might be associated with the violent method of suicide attempts.

METHODS

The study group consisted of 163 inpatients who attempted suicide. Blood samples were collected at the beginning of hospitalization to measure total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein, very-low-density lipoprotein (VLDL), triglycerides, and NLR. Descriptive analyses of the total sample were performed. The included patients were divided into two groups according to violent/nonviolent method. Groups were compared in terms of lipid (MANCOVAs).

RESULTS

Plasma levels of total cholesterol (F = 5.66; P = .02), LDL (F = 4.94; P = .03), VLDL (F = 5.66; P = .02), and NLR (F = 8.17; P < .01) resulted to be significantly lower in patients that used a violent method compared to patients who attempted suicide with a nonviolent method.

CONCLUSIONS

Low cholesterol, LDL, and VLDL levels as well as low NLR value were associated with a violent method of suicide attempt in patients with mental disorders. Further studies are needed to confirm these results.

Interleukin-18 signaling system links to agitation in severe mental disorders

OBJECTIVE

Agitation is a challenging clinical feature in severe mental disorders, but its biological correlates are largely unknown. Inflammasome-related abnormalities have been linked to severe mental disorders and implicated in animal models of agitation. We investigated if levels of circulating inflammasome-related immune markers were associated with agitation in severe mental disorders.

METHODS

Individuals with a psychotic or affective disorder (N = 660) underwent blood sampling and clinical characterization. Plasma levels of interleukin (IL)-18, IL-18 binding protein (IL-18BP), IL-18 receptor 1 (IL-18R1), IL-18 receptor accessory protein (IL-18RAP), and IL-1 receptor antagonist (IL-1RA) were measured. Agitation levels were estimated with the Positive and Negative Syndrome Scale Excited Component. Multiple linear- and logistic regression were used to investigate the associations between agitation and the immune markers, while controlling for confounders. The influence of psychotic and affective symptoms was assessed in follow-up analyses.

RESULTS

Agitation was positively associated with IL-18BP (β = 0.13, t = 3.41, p = 0.0007) after controlling for multiple confounders, including BMI, smoking, medication, and substance use. Adjustment for psychotic, manic, and depressive symptoms did not affect the results. There were no significant associations between agitation and the other investigated immune markers (IL-1RA (β = 0.06, t = 1.27, p = 0.20), IL-18 (β = 0.05, t = 1.25, p = 0.21), IL-18R1 (β = 0.04, t = 1.01, p = 0.31), IL-18RAP (odds ratio = 0.96, p = 0.30)). In a subsample (N = 463), we also adjusted for cortisol levels, which yielded unaltered results.

CONCLUSION

Our findings add to the accumulating evidence of immune system disturbances in severe mental disorders and suggest the IL-18 system as a part of the biological correlate of agitation independent of affective and psychotic symptoms.

The Neutrophil-Lymphocyte Ratio Is Positively Correlated with Aggression in Schizophrenia

To find biomarkers to assess the risk of aggression, we looked at the association between aggression and levels of body inflammation in patients with schizophrenia. The Modified Overt Aggression Scale (MOAS) score was used to divide the aggressive (n = 72) and nonaggressive (n = 141) groups. The Brief Psychiatric Rating Scale (BPRS) is a tool for determining the severity of a patient's condition. After measuring the number of inflammatory cells in the peripheral blood, the platelet-lymphocyte ratio (PLR), neutrophil-lymphocyte ratio (NLR), and monocyte-lymphocyte ratio (MLR) were estimated. We investigated the relationship between aggressive behavior, bodily inflammation, and BPRS. Before therapy, the aggressive group's BPRS score, white blood cell (WBC) count, neutrophil count, monocyte count, NLR, and MLR were considerably more significant than the nonaggressive group's. After therapy, statistically significant variations in total BPRS score and neutrophil count between the two groups. According to correlation analysis before and after treatment, aggressive behavior was positively connected with neutrophil count, NLR, and BPRS score. The presence of aggressive behavior in schizophrenic patients indicates the severity of the disorder to some degree. NLR can be used as an objective biomarker to quickly assess the risk of aggression in schizophrenic patients.

Sex differences in the blood-brain barrier: Implications for mental health

Prevalence of mental disorders, including major depressive disorder (MDD), bipolar disorder (BD) and schizophrenia (SZ) are increasing at alarming rates in our societies. Growing evidence points toward major sex differences in these conditions, and high rates of treatment resistance support the need to consider novel biological mechanisms outside of neuronal function to gain mechanistic insights that could lead to innovative therapies. Blood-brain barrier alterations have been reported in MDD, BD and SZ. Here, we provide an overview of sex-specific immune, endocrine, vascular and transcriptional-mediated changes that could affect neurovascular integrity and possibly contribute to the pathogenesis of mental disorders. We also identify pitfalls in current literature and highlight promising vascular biomarkers. Better understanding of how these adaptations can contribute to mental health status is essential not only in the context of MDD, BD and SZ but also cardiovascular diseases and stroke which are associated with higher prevalence of these conditions.

Increased C-reactive protein concentration and suicidal behavior in people with psychiatric disorders: A systematic review and meta-analysis

OBJECTIVE

Suicide is a leading cause of death worldwide. Identifying factors associated with suicidality (suicidal ideation [SI]/suicidal behavior) could increase our understanding of the pathophysiological underpinnings of suicide and improve its prevention.

METHODS

We conducted a systematic review (PubMed/PsycInfo/Cochrane databases, up to September 2020) and random-effect meta-analysis including observational studies comparing peripheral C-reactive protein (CRP) levels in suicidal versus non-suicidal patients affected by any psychiatric disorder and healthy controls (HC). Primary outcome was the CRP standardized mean difference (SMD) between patients with high suicidality versus those with absent or low suicidality. Secondary outcomes were SMD of CRP levels between those with suicide attempt versus no suicide attempt, as well as between those with (high) versus low or absent SI. Quality of included studies was measured with Newcastle-Ottawa scale.

RESULTS

Out of initial 550 references, 21 observational studies involving 7682 subjects (7445 with mood disorders or first-episode psychosis, 237 HC) were included. A significant association of CRP levels with suicidality (SMD 0.688, 95% CI 0.476-0.9, p < 0.001) emerged. CRP levels were higher in individuals with high SI (SMD 1.145, 95% CI 0.273-2.018, p = 0.010) and in those with suicide attempt (SMD 0.549, 95%CI 0.363-0.735, p < 0.001) than non-suicidal individuals (either patients or HC). Main analyses were confirmed in sensitivity analysis (removing HC), and after adjusting for publication bias. The cross-sectional design of included studies, and the high heterogeneity of diagnosis and treatment limit the generalizability of these results. Median quality of included studies was high.

CONCLUSION

CRP is associated with higher suicidality in patients with mental disorders. Large cohort studies longitudinally monitoring CRP levels are needed to explore its longitudinal association with suicidality.

Bacterial Translocation Associates With Aggression in Schizophrenia Inpatients

Objective: Accumulating evidence indicates that inflammation abnormalities may contribute to aggression behaviors in psychotic patients, however, the possible sources of inflammation remain elusive. We aimed to evaluate the associations among aggression, inflammation, and bacterial translocation (BT) in aggression-affected schizophrenia (ScZ) inpatients with 2 weeks of antipsychotics discontinuation.

Methods: Serum specimens collected from 112 aggression and 112 non-aggression individuals with ScZ and 56 healthy adults were used for quantifications of inflammation- or BT-related biomarkers. Aggression severity was assessed by Modified Overt Aggression Scale (MOAS).

Results: Proinflammation phenotype dominated and leaky gut-induced BT occurred only in cases with ScZ with a history of aggression, and the MOAS score positively related to levels of C-reactive protein, interleukin (IL)-6, IL-1β, and tumor necrosis factor-α. Furthermore, serum levels of BT-derived lipopolysaccharide (LPS), as well as LPS-responded soluble CD14, were not only positively correlated with levels of above proinflammation mediators but also the total MOAS score and subscore for aggression against objects or others.

Conclusion: Our results collectively demonstrate the presence of leaky gut and further correlate BT-derived LPS and soluble CD14 to onset or severity of aggression possibly by driving proinflammation response in inpatients with ScZ, which indicates that BT may be a novel anti-inflammation therapeutic target for aggression prophylaxis.

Serum level of high sensitive C-reactive protein and IL - 6 markers in patients with treatment-resistant schizophrenia in Ethiopia: a comparative study

BACKGROUND

Accumulating evidence indicates that schizophrenia is accompanied by significant activation of the immune system; however, there is limited data from low and middle-income countries (LMIC). Inflammatory markers may be more relevant in LMIC settings where infectious conditions are more prevalent and may thus play some role in the causation and maintenance of schizophrenia. The aim of this study was to assess the level of inflammatory markers high sensitive C-reactive protein (hsCRP) and interleukin-6 (IL-6) in patients with schizophrenia.

MATERIALS AND METHODS

The study population consisted of a total of 132 study participants; 82 participants with schizophrenia and 50 controls. hsCRP and IL-6 were measured using Cobas Integra 400 Plus and Cobas e 411 analysers respectively.

RESULTS

The levels of hsCRP and IL-6 were significantly increased among participants with schizophrenia compared to controls: hsCRP mean value 2.87 ± 5.6 vs 0.67 ± 0.6 mg/L; IL-6 mean value 6.63 ± 5.6 vs 3.37 ± 4.0 pg/ml. Controlling for potential confounders (age, sex and body mass index), having a diagnosis of schizophrenia remained significantly associated with increased hsCRP and IL-6.

CONCLUSION

The results confirm that inflammatory processes may have a role in the pathophysiology of schizophrenia regardless of setting. Despite failure of some interventions with anti-inflammatory properties, interventions to reduce inflammation are still worth pursuing.

Associations of C-Reactive Protein, Free Triiodothyronine, Thyroid Stimulating Hormone and Creatinine Levels with Agitation in Patients with Schizophrenia: A Comparative Cross-Sectional Study

PURPOSE

Agitation is prevalent among inpatients with schizophrenia. The aim of this study was to investigate whether biochemical parameters are associated with agitation in schizophrenia.

PATIENTS AND METHODS

Agitation was evaluated by the Positive and Negative Syndrome Scale-Excited Component questionnaire (PANSS-EC). Fasting serum levels of C-reactive protein (CRP), free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), uric acid (UA), creatinine, glucose and lipids were measured.

RESULTS

The analysis included 154 inpatients with schizophrenia (71 with agitation, 83 without agitation) and 75 healthy control subjects. Patients with schizophrenia and agitation had higher serum levels of CRP, FT3, FT4 and UA as well as lower levels of serum TSH and creatinine than patients without agitation (all P < 0.05). Multivariate logistic regression analysis indicated that serum CRP (odds ratio [OR] = 1.470, P = 0.001), FT3 (OR = 13.026, P < 0.001), TSH (OR = 0.758, P = 0.033) and creatinine (OR = 0.965, P = 0.004) were significantly associated with agitation in schizophrenia. CRP, FT3, TSH and creatinine achieved an area under the ROC curve of 0.626, 0.728, 0.620 and 0.663 respectively in discriminating schizophrenia with or without agitation.

CONCLUSION

Increased serum CRP and FT3 levels and decreased serum TSH and creatinine levels are independent risk factors for agitation in hospitalized patients with schizophrenia. Inflammation, thyroid hormones and renal function may be involved in the pathogenesis of agitation in schizophrenia.

Higher Serum C-Reactive Protein Levels in Catatonic Patients: A Comparison to Non-catatonic Patients and Healthy Controls

Catatonia is a psychomotor syndrome defined by a constellation of predominantly motor symptoms. The aim of the present study was to determine whether recently admitted psychiatric patients with catatonia exhibited higher serum C-reactive protein (hs-CRP) levels compared to non-catatonic psychiatric patients and healthy controls (HCs). Recently admitted psychiatric patients were screened and evaluated for the catatonia syndrome using the Bush-Francis Catatonia Rating Scale and the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). The study sample was formed by 150 individuals (39 male and 111 female), including 51 catatonic patients, 55 non-catatonic patients, and 44 HCs. Serum hs-CRP levels were processed with the enzyme-linked immunosorbent assay. Serum levels of creatine kinase (CK), adrenocorticotropic hormone (ACTH), immunoglobulin G (IgG), complement component 3 (C3), and complement component 4 (C4) were also determined. There was a significantly higher percentage of patients with high inflammatory levels (hs-CRP > 3000ng/ml) in the catatonic (43.1%) than in the non-catatonic (14.5%) or HCs group (9.1%) (χ 2 =18.9, P < .001). Logistic regression showed that catatonic patients had significantly higher hs-CRP levels compared to non-catatonic patients even after controlling for other clinical and laboratory variables (OR = 3.52, P = .015, 95% CI 1.28-9.79). Multiple linear regression analysis revealed that log-transformed hs-CRP was independently predicted by body mass index and log-transformed C4, ACTH, and Cortisol in catatonic patients. Findings of the present study suggest that catatonia is specifically linked to a higher level of systemic inflammation, not merely attributable to the overall psychopathology, or alterations in the stress level and complement system.

C-Reactive Protein/Albumin and Neutrophil/Albumin Ratios as Novel Inflammatory Markers in Patients with Schizophrenia

OBJECTIVE

Peripheral biomarker studies in schizophrenia are insufficient to correspond to whether inflammatory markers are trait- or state-related. The main objective of this study was to compare novel biomarkers C-reactive protein/albumin ratio (CAR), neutrophil/albumin ratio (NAR), and complete blood count-derived inflammatory markers; neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), monocyte/lymphocyte ratio (MLR), red-cell distribution width (RDW), and mean platelet volume (MPV) between patients with acutely exacerbated and remitted schizophrenia and healthy controls.

METHODS

Anonymous data of a total of 618 patients with schizophrenia (179 in remission, 439 with acute exacerbation) and 445 psychiatrically and medically healthy subjects admitted to outpatient units were included. One-way ANOVA with Tukey's HSD post-hoc test, Pearson's correlation test, receiver operating characteristic analysis, and binomial logistic regression analysis were performed.

RESULTS

CAR, NAR, NLR, PLR, MLR, RDW, MPV values were found higher in patients with schizophrenia than in healthy subjects. Except for NAR (p=0.007), none of the markers differed between acute exacerbation and remission. As a cut-off value of CAR, 0.388 differentiated patients with schizophrenia from controls (sensitivity 81%, specificity 81%). CAR, NAR, and MPV significantly predicted the diagnosis of schizophrenia.

CONCLUSION

CAR and NAR are reliable biomarkers of inflammation and a combination of inflammatory markers including CAR and NAR could be used to reflect the increased inflammatory status in schizophrenia, regardless of relapse or remission.

Cytokines in agitated and non-agitated patients admitted to an acute psychiatric department: A cross-sectional study

BACKGROUND

Different psychiatric diagnostic groups have been reported to have cytokine levels deviating from healthy controls. In acute clinical settings however, the specific challenging symptoms and signs are more important than a diagnostic group. Thus, exploration of cytokines and immune activity and their role in specific symptoms is important. Reports in this field so far are sparse.

OBJECTIVE

In the present study, we aimed to examine the association between immune activity measured as levels of cytokines and agitation (independent of diagnostic group) in patients admitted to an acute psychiatric inpatient department.

METHODS

A total of 316 patients admitted to an acute psychiatric inpatient department were included. Thirty-nine patients with psychosis were subject to subgroup analyses. Agitation was assessed by the Positive and Negative Syndrome Scale, Excitement Component (PANSS-EC). Based on PANNS-EC patients were stratified into two groups: 67 agitated patients and 249 non-agitated patients. Serum concentrations of the following immune markers were measured: interleukin (IL) -1β, IL-4, IL-6, IL-10, tumor necrosis factor (TNF) -α, interferon (IFN) -γ and transforming growth factor (TGF) -β.

RESULTS

Serum levels of TNF-α were significantly higher in patients with agitation compared to those without, both when all patients were included in the analyses (p = 0.004) and in the psychosis group (p = 0.027). After correcting for multiple testing, only the findings in the total population remained significant.

CONCLUSIONS

Our findings suggest an association between TNF-α and agitation in an acute psychiatric population. A similar trend was reproduced to the psychosis subgroup. This suggests that agitation might be an independent entity associated with cytokines across different diagnostic groups.

Serum Levels of High Sensitivity C-reactive Protein in Drug-naÏve First-episode Psychosis and Acute Exacerbation of Schizophrenia

OBJECTIVE

Findings about inflammatory processes in schizophrenia are increasing day by day. Inflammatory processes in schizophrenia are associated with both its etiology and clinical symptoms. Serum high-sensitivity C-reactive protein (hsCRP) is also one of these inflammatory processes. Particularly, it is thought to be closely related to clinical findings of patients with schizophrenia.

METHODS

In this study, the relationship between clinical findings of hsCRP levels of patients with drug-naÏve first-episode psychosis (FEP) and patients with schizophrenia in acute exacerbation phase is investigated. Clinical findings, psychometric properties (the Scale for the Assessment of Positive Symptoms, the Scale for the Assessment of Negative Symptoms, Brief Psychiatric Rating Scale), and hsCRP levels of patients were compared.

RESULTS

Forty-eight patients with FEP, 74 patients with schizophrenia in acute exacerbation phase and 54 healthy controlled volunteers are included in the study. The most substantial finding in the study is that there is a positive correlation between hsCRP levels and severity of positive symptoms of both patient groups, with FEP and with schizophrenia. The second most substantial finding is there is no significant difference between patients with FEP and schizophrenia, in terms of hsCRP.

CONCLUSION

The relationship between hsCRP and positive symptom severity in two groups of patients supports the inflammatory hypothesis in the etiopathogenesis of schizophrenia. This finding is supportive of close relation between inflammatory processes and clinical findings of patient with schizophrenia.

Neutrophil-to-lymphocyte ratio in schizophrenia: A systematic review and meta-analysis

BACKGROUND

The immune system appears to be dysregulated in schizophrenia (SZ). The potential prognostic or diagnostic value of neutrophil-to-lymphocyte ratio (NLR), an inexpensive proxy marker for a wide spectrum of conditions, has not been established in SZ. We seek to investigate a) whether NLR is increased in SZ patients, b) if this difference in more prominent in relapsed SZ or first-episode psychosis.

METHODS

A structured algorithm was applied in MEDLINE (1946-2018), PsychInfo, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL) (1999-2018), PSYNDEX (1984-2017) and Clinicaltrials.gov (2008-2018) databases.

RESULTS

Through the database search, 1023 articles were screened. Ten studies (804 SZ patients, 671 controls) were included in the meta-analysis. In SZ patients, the NLR was increased by 0.65 (95% CI: 0.54, 0.86, p < 10^-5). This difference was significant in both acute relapse and first-episode psychosis subgroups. Studies of moderate and high quality also showed a significant NLR increase in SZ patients (I² = 0%). Meta-regression analysis showed that the polymorphonuclear count and antipsychotic use may confound the result. In leave-one-out meta-analysis, no study altered the significance of the result when omitted.

CONCLUSIONS

NLR in SZ patients is increased, both in chronic disease and in first-episode psychosis. Baseline characteristics, such as polymorphonuclear count and antipsychotic use, may affect its accuracy. The application of this marker in clinical practice requires the description of its normal values in the general population, its potential change after antipsychotic administration and its correlation with disease activity. A large-scale, prospective study design would resolve these issues.

An inflammatory profile linked to increased suicide risk

BACKGROUND

Suicide risk assessments are often challenging for clinicians, and therefore, biological markers are warranted as guiding tools in these assessments. Suicidal patients display increased cytokine levels in peripheral blood, although the composite inflammatory profile in the subjects is still unknown. It is also not yet established whether certain inflammatory changes are specific to suicidal subjects. To address this, we measured 45 immunobiological factors in peripheral blood and identified the biological profiles associated with cross-diagnostic suicide risk and depression, respectively.

METHODS

Sixty-six women with mood and anxiety disorders underwent computerized adaptive testing for mental health, assessing depression and suicide risk. Weighted correlation network analysis was used to uncover system level associations between suicide risk, depression, and the immunobiological factors in plasma. Secondary regression models were used to establish the sensitivity of the results to potential confounders, including age, body mass index (BMI), treatment and symptoms of depression and anxiety.

RESULTS

The biological profile of patients assessed to be at increased suicide risk differed from that associated with depression. At the system level, a biological cluster containing increased levels of interleukin-6, lymphocytes, monocytes, white blood cell count and polymorphonuclear leukocyte count significantly impacted suicide risk, with the latter two inferring the strongest influence. The cytokine interleukin-8 was independently and negatively associated with increased suicide risk. The results remained after adjusting for confounders.

LIMITATIONS

This study is cross-sectional and not designed to prove causality.

DISCUSSION

A unique immunobiological profile was linked to increased suicide risk. The profile was different from that observed in patients with depressive symptoms, and indicates that granulocyte mediated biological mechanisms could be activated in patients at risk for suicide.

Correlations between Body Mass Index, Plasma High-Sensitivity C-Reactive Protein and Lipids in Patients with Schizophrenia

High prevalence of obesity in individuals with schizophrenia, associated with metabolic syndrome, leads to high rate of premature deaths from cardiovascular disease (CVD) in this population. Body mass index (BMI) and C-reactive protein (CRP) are correlated in the general population but this relationship has not been fully elucidated in patients with schizophrenia. We aimed to evaluate the correlation between BMI and CRP while relating both variables to plasma lipids in patients with schizophrenia. BMI, fasting high sensitivity CRP (hs-CRP), cotinine, and lipids were measured in 106 patients with schizophrenia (diagnosis confirmed with MINI). Pearson's and partial correlations (adjusting for age, sex, race, education and cotinine) between BMI, hs-CRP and lipids were calculated. Based on BMI, the patients were divided into normal-weight vs. overweight/obese and t-tests and linear regression were done to compare hs-CRP and lipids in the 2 groups. BMI positively correlated with hs-CRP (r = 0.29, p = 0.004). BMI and hs-CRP negatively correlated with HDL in the total sample (r = -0.29, p = 0.004; r = -0.37, p < 0.001 respectively). Furthermore, hs-CRP negatively correlated with HDL in overweight/obese patients (r = -0.41, p = 0.003), but not in normal-weight patients. hs-CRP and triglycerides were higher (1.62 ± 0.09 mg/L vs. 0.56 ± 0.08 mg/L, p < 0.001; 121.77 ± 8.96 mg/dL vs. 91.23 ± 6.52 mg/dL, p = 0.008 respectively) and HDL lower (39.55 ± 1.48 mg/dL vs. 50.68 ± 2.24 mg/dL, p < 0.001) in overweight/obese patients. Being overweight/obese is associated with increased inflammation and dyslipidemia in patients with schizophrenia. Effective interventions to prevent weight gain in schizophrenia are urgently needed.

C-Reactive Protein: Higher During Acute Psychotic Episodes and Related to Cortical Thickness in Schizophrenia and Healthy Controls

There is increasing evidence for the role of inflammation in schizophrenia, yet the stability of increased peripheral inflammation in acute psychosis and the degree to which peripheral inflammation relates to cortical thickness, a measure of the degree of neuropathology, are unknown. In independent samples, we assessed the peripheral inflammation marker C-reactive protein (CRP) to determine the extent to which: (1) CRP was elevated and stable across admissions for acute psychosis, (2) cognition, daily function and symptom severity are characteristic of chronically ill patients with schizophrenia displaying elevated CRP, and (3) CRP levels predict cortical thickness. Study 1 assessed peripheral CRP (primary outcome) and other blood measures in 174/280 people with acute psychosis while Study 2 assessed peripheral CRP, cognition and cortical thickness (primary outcomes), symptoms, and daily function in 85/97 chronically ill patients with schizophrenia and 71/87 healthy controls. In acute psychosis, CRP and neutrophil-to-lymphocyte ratio were significantly elevated relative to a normal cutoff (with 59.8% of patients having elevated CRP) which remained elevated across admissions. CRP was significantly elevated in 43% of chronically ill patients with schizophrenia compared to 20% in controls. Elevated CRP patients displayed significantly worse working memory and CRP was inversely correlated with cortical thickness in frontal, insula, and temporal brain regions. This work supports the role of inflammation in psychotic illnesses and suggests that use of peripheral markers (e.g., CRP) in conjunction with diagnosis could be used to identify patients with more cortical neuropathology and cognitive deficits.

Association between Elevated C-Reactive Protein and Manic Polarity in Acute Psychiatric Inpatients with Affective Symptomatology

The interplay between the immune system and behaviour is of increasing interest in psychiatry research. Specifically, accumulating data points to a link between inflammation and psychopathology, including affective symptomatology. We investigated the association between inflammation and affective polarity in psychiatric inpatients who were hospitalized due to an affective exacerbation. Data was collected retrospectively and comparisons were made between manic and depressed patients. C-reactive protein (CRP), a general laboratory marker of immune activation and inflammation, was used as a non-specific inflammatory biomarker. Age, smoking and body mass index were considered covariates. Manic polarity (n = 89) was associated with statistically significant elevated CRP levels compared to depressed polarity (n = 44, 56%; p = 0.036), after controlling for covariates. No differences were observed in CRP levels across Diagnostic and Statistical Manual of Mental Disorders-IV Edition-Text Revised psychiatric diagnoses. These findings suggest a transdiagnostic association between inflammation and manic polarity in affective inpatients.

Elevated neutrophil to lymphocyte ratio in non-affective psychotic adolescent inpatients: Evidence for early association between inflammation and psychosis

Accumulating data suggest an association between inflammation and schizophrenia and related psychosis. While several studies have established this immune-psychosis association in adult schizophrenia patients, there is very limited data associating inflammation with acute psychosis in children and adolescents. The ratio between neutrophils and lymphocyte, computed from routine blood counts, has been shown to correlate with traditional markers of inflammation, and is therefore considered a proxy-marker for inflammation. Here we report elevated neutrophil to lymphocyte ratio and total leukocyte count in psychotic adolescent inpatients (n = 81, mean age 14.7 years, 52% males) compared to non-psychotic adolescent inpatient (n = 285, mean age 15.9 years, 58% males), in a population of adolescent inpatients with no affective symptomatology. The elevated neutrophil to lymphocyte ratio remained significant after controlling for confounders such as age, BMI, smoking and antipsychotic medication. In a subset of psychotic adolescent inpatients (n = 20, mean duration between blood test 157 days), we found significant decrease in neutrophil to lymphocyte ratio at clinical remission compared with the acute psychotic state. The results suggest that psychosis is associated with peripheral markers of inflammation early in the course of psychiatric pathology, and that inflammation may represent a state that accompanies psychosis and decreases during clinical remission.

C-Reactive Protein as a Peripheral Biomarker in Schizophrenia. An Updated Systematic Review

Objectives: The objective of this systematic review was to synthetize the published data on the relationships between elevated blood C-reactive protein (CRP) levels and schizophrenia (SZ) onset risk, illness characteristics and treatments, cognition and physical health. Method: The systematic bibliographic searches have been carried out according to the Cochrane methodology. Medline, web of science, Google Scholar with each database being searched from inception to November 2017. Results: 53 studies were included in the present review. While meta-analyses including case-control studies suggest a clear association between CRP and SZ, one other study has suggested that CRP-associated genes were associated with a lower risk of SZ onset. Increased CRP has been significantly associated with positive symptoms in acute phase psychosis, while studies including community-dwelling stabilized subjects did not find such an association. Abnormal CRP has been associated with a wide range of cognitive impairment in SZ stabilized individuals. Body Mass index has been extensively associated with increased CRP in SZ subjects; and increased CRP has been identified as a risk factor for metabolic syndrome and cardiovascular risk in SZ subjects. Increased CRP has also been associated with high nicotine dependence in SZ smokers and one study has suggested that increased CRP was associated with sedentary behavior. Conclusion: In the light of the above-mentioned studies, increased hs-CRP may be reasonably suggested as a marker for SZ onset risk, as well as a risk factor for increased positive symptoms, cognitive impairment, hypovitaminosis D, microbiota disturbances, cardiovascular and metabolic syndrome risk in SZ subjects, and increased nicotine dependence in SZ smokers. In case of increased CRP levels, anti-inflammatory strategies (add-on anti-inflammatory drugs including aspirin and omega 3 fatty acids, vitamin D supplementation, physical activity, probiotics) should be also further evaluated. Limits: Most of the studies were cross-sectional and cohort studies are needed to determine the temporal relationship between increased CRP and the psychiatric outcomes.

Protein-C Reactive as Biomarker Predictor of Schizophrenia Phases of Illness? A Systematic Review

BACKGROUND

Schizophrenia is a complex illness in which genetic, environmental, and epigenetic components have been implicated. However, recently, psychiatric disorders appear to be related to a chronic inflammatory state, at the level of specific cerebral areas which have been found as well impaired and responsible for schizophrenia symptomatology. Hence, a role of inflammatory mediators and cytokines has been as well defined. Accordingly, the role of an acute inflammatory phase protein, the C-reactive protein (CRP) has been recently investigated.

OBJECTIVE

The objective of the present study is to evaluate how PCR may represent a biomarker in schizophrenia, i.e. correlated with illness phases and/or clinical manifestation and/or psychopathological severity.

METHODS

A systematic review was here carried out by searching the following keywords ((C-reactive protein AND ((schizophrenia) OR (psychotic disorder))) for the topics 'PCR' and 'Schizophrenia', by using MESH terms.

RESULTS

An immune dysfunction and inflammation have been described amongst schizophrenic patients. Findings reported elevated CRP levels in schizophrenia, mainly correlated with the severity of illness and during the recrudescent phase. CRP levels are higher when catatonic features, negative symptomatology and aggressiveness are associated. CRP levels appeared not to be related to suicidal behaviour and ideation.

CONCLUSION

CRP and its blood levels have been reported higher amongst schizophrenic patients, by suggesting a role of inflammation in the pathogenesis of schizophrenia. Further studies are needed to better understand if CRP may be considered a biomarker in schizophrenia.

Association between high sensitivity CRP and suicidal ideation in the Korean general population

Inflammation has been linked with a potential critical role in suicide. The purpose of this study is to examine the relation of CRP with suicidal behavior in the Korean population. We conducted a cross-sectional study in 4693 Korean adults aged 20-81 years who participated in the 2015 Korea National Health and Nutrition Examination Survey. High sensitivity CRP levels were measured by immunoturbidimetric method. Suicidal ideation and suicide attempt were assessed by using a questionnaire. Data were analyzed in 2017. Multiple logistic regression analysis was used to compute odds ratios (ORs) and 95% confidence intervals (CIs). The prevalence of suicidal ideation was 4.9% and that of suicide attempt was 0.4%. Suicidal ideation was more prevalent in the highest compared with the lowest serum CRP quartile (OR, 1.79; 95% CI, 1.11-2.89) after adjustment for age, sex, household income, educational level, marital status, employment status, alcohol dependency, current smoking, physical activity, BMI, sleep duration, number of chronic diseases, restriction on activity, subjective health status, perceived stress, depression and depressive mood (p for trend<0.05). In conclusion, elevated levels of CRP were associated with an increased risk of suicidal ideation among South Korean adults.

Chronic low-grade peripheral inflammation is associated with severe nicotine dependence in schizophrenia: results from the national multicentric FACE-SZ cohort

Chronic peripheral inflammation (CPI) has been associated with cognitive impairment in schizophrenia (SZ). However, its sources remain unclear, more specifically it is not known whether tobacco smoking is a source of inflammation or not in SZ subjects. Moreover, nicotine (NIC), the major psychoactive compound of tobacco, shows strong anti-inflammatory properties in vitro, as well as inducing a severe biological dependence when administered repeatedly. The objective of the present study was to determine if CPI was associated with tobacco smoking and/or NIC dependence in schizophrenia. Three hundred and forty five stabilized community-dwelling SZ subjects aged 16 years or older (mean age = 32 years, 73% male) were consecutively included in the network of the FondaMental Expert Centers for Schizophrenia and assessed with validated scales. CPI was defined by a highly sensitive C-reactive protein (hsCRP) ≥3 mg/L. Current tobacco status was self-declared. Severe NIC dependence was defined by a Fagerstrom Test for Nicotine Dependence score ≥7. Overall, 159 (46.1%) were non-smokers, 117 (33.9%) and 69 (20%) were current tobacco smokers with, respectively, low and severe nicotine dependence. In a multivariate model, CPI remained associated with severe NIC dependence (29 vs 15%, OR = 2.8, p = 0.003) and body mass index (OR = 1.1, p < 0.0001), independently of socio-demographic characteristics and antidepressant intake. No association of CPI with low to moderate tobacco smoking dependence, number of daily smoked cigarettes, cannabis use, alcohol use or illness characteristics was found (all p > 0.05). CPI was associated with severe NIC dependence but not with tobacco smoking with low to moderate NIC dependence in SZ, independently of socio-demographic variables, body mass index, alcohol consumption and antidepressant intake. This result highlights the potential CPI consequences of the high prevalence of heavy tobacco smoking in SZ, indicating the importance of new therapeutic strategies for tobacco cessation in SZ.

Association between C-reactive protein and risk of schizophrenia: An updated meta-analysis

C-reactive protein (CRP) has been indicated to be associated with the pathogenesis of schizophrenia (SZ) and other psychiatric disorders. The aim of this study is to investigate whether peripheral blood CRP levels are associated with the risk of SZ. We searched literature from databases of Pubmed, Embase and the Cochrane Library from inception to November 1, 2016 for studies that reported serum or plasma CRP levels in patients with SZ and non-SZ controls. At least two reviewers decided on eligibility and extracted data from included studies. Random effects meta-analyses were performed using standardized mean difference (SMD) as the effect estimate of the differences in CRP levels between subjects with SZ and healthy controls. We identified 18 studies representing 1963 patients with SZ and 3683 non-SZ controls. Compared with non-schizophrenics, blood CRP levels were moderately increased in people with SZ (SMD 0.53, 95% CI 0.30 to 0.76) irrespective of study region, sample size of included studies, patient mean age, age of SZ onset and patient body mass index. Publication bias was not detected through Egger's linear regression test (P = 0.292). We noticed that patients in Asia or Africa (n = 6, SMD 0.73, 95% CI 0.26 to 1.21) and whose age less than 30 years (n = 5, SMD 0.76, 95% CI 0.07 to 1.58) had substantially higher CRP levels. Our study provides evidence that higher CRP levels are associated with increased risk of SZ, especially for young adult patients less than 30 years. Further large-scale studies are strongly warranted to further confirm this association.

C-reactive protein and white blood cell levels in schizophrenia, bipolar disorders and depression - associations with mortality and psychiatric outcomes: a population-based study

BACKGROUND

Mental disorders have been associated with increased levels of inflammatory markers, which can affect disease trajectories. We aimed to assess levels of C-reactive protein (CRP) and white blood cells (WBC) across individuals with schizophrenia, bipolar disorder, and depression, and to investigate associations with subsequent psychiatric admission and mortality.

METHODS

We identified all adults in the Central Denmark Region during 2000-2012 with a first diagnosis of schizophrenia, bipolar disorder, or depression and a baseline measurement of CRP and/or WBC count. We followed these individuals until outcome of interest (psychiatric admission or death), emigration or December 31, 2012, using Cox regression analysis to estimate hazard ratios (HRs).

RESULTS

Baseline median CRP differed significantly between mental disorders (P=0.01) being highest in individuals with bipolar disorder (3.5mg/L) (particularly during manic states, 3.9mg/L), followed by schizophrenia (3.1mg/L), and depression (2.8mg/L), while baseline WBC count did not differ (median 7.1×10⁹/L). Elevated CRP levels were associated with increased all-cause mortality by adjusted HRs of 1.56 (95% CI: 1.02-2.38) for levels 3-10mg/L and 2.07 (95% CI: 1.30-3.29) for levels above 10mg/L compared to individuals with levels below 3mg/L. WBC counts were not associated with all-cause mortality. No association was observed between levels of the inflammatory markers and subsequent psychiatric admissions.

CONCLUSIONS

People with severe mental disorders had increased inflammatory markers at first diagnosis, and elevated CRP levels were associated with increased mortality. Thorough screening for physical diseases is of utmost importance among individuals who are diagnosed with severe mental disorder.

Long-term consumption of sugar-sweetened beverage during the growth period promotes social aggression in adult mice with proinflammatory responses in the brain

Overconsumption of sugar-sweetened beverages (SSBs) is known to be a key contributor to the obesity epidemic; however, its effects on behavioral changes are yet to be fully studied. In the present study, we examined the long-term effects of SSB on social aggression in mice. Three-week-old weaned mice started to drink either a 30 w/v% sucrose solution (S30), plain water (CT), or an aspartame solution with sweetness equivalent to the sucrose solution (A30) and continued to drink until they were 11-week-old adults. Aggressive behaviors were assessed by the resident-intruder test. We found that SSB significantly promoted social aggression, accompanied by heightened serum corticosterone and reduced body weight. To understand the underlying mechanism, we performed transcriptome analyses of brain. The profiles of mice on S30 were dramatically different from those on CT or A30. Transcriptional networks related to immunological function were significantly dysregulated by SSB. FACS analysis of mice on S30 revealed increased numbers of inflammatory cells in peripheral blood. Interestingly, the artificial sweetener failed to mimic the effects of sugar on social aggression and inflammatory responses. These results demonstrate that SSB promotes aggressive behaviors and provide evidence that sugar reduction strategies may be useful in efforts to prevent social aggression.

Modified Mediterranean Diet for Enrichment of Short Chain Fatty Acids: Potential Adjunctive Therapeutic to Target Immune and Metabolic Dysfunction in Schizophrenia?

Growing interest in gut and digestive processes and their potential link to brain and peripheral based inflammation or biobehavioral phenotypes has led to an increasing number of basic and translational scientific reports focused on the role of gut microbiota within the context of neuropsychiatric disorders. However, the effect of dietary modification on specific gut metabolites, in association with immune, metabolic, and psychopathological functioning in schizophrenia spectrum disorders has not been well characterized. The short chain fatty acids (SCFA) acetate, butyrate, and propionate, major metabolites derived from fermentation of dietary fibers by gut microbes, interact with multiple immune and metabolic pathways. The specific pathways that SCFA are thought to target, are dysregulated in cardiovascular disease, type II diabetes, and systemic inflammation. Most notably, these disorders are consistently linked to an attenuated lifespan in schizophrenia. Although, unhealthy dietary intake patterns and increased prevalence of immune and metabolic dysfunction has been observed in people with schizophrenia; dietary interventions have not been well utilized to target immune or metabolic illness. Prior schizophrenia patient trials primarily focused on the effects of gluten free diets. Findings from these studies indicate that a diet avoiding gluten benefits a limited subset of patients, individuals with celiac disease or non-celiac gluten sensitivity. Therefore, alternative dietary and nutritional modifications such as high-fiber, Mediterranean style, diets that enrich the production of SCFA, while being associated with a minimal likelihood of adverse events, may improve immune and cardiovascular outcomes linked to premature mortality in schizophrenia. With a growing literature demonstrating that SCFA can cross the blood brain barrier and target key inflammatory and metabolic pathways, this article highlights enriching dietary intake for SCFA as a potential adjunctive therapy for people with schizophrenia.

Serum high-sensitivity C-reactive protein: A delicate sentinel elevated in drug-free acutely agitated patients with schizophrenia

Increased levels of high-sensitivity C reactive protein (hsCRP) have been reported in schizophrenia, but to date, no study is designed to examine serum hsCRP in acutely agitated patients with schizophrenia, an extreme state that requires immediate diagnosis and medical treatment. Serum hsCRP levels were assessed in 32 clinically acutely agitated patients and 42 healthy control subjects matched for demographic properties. Further, serum hsCRP levels in acutely agitated patients were compared with control subjects and with the levels after the patients were treated with anti-psychiatric medications. Meanwhile, the influence of clinical subtypes, family history, and gender, as well as the levels of white blood cell (WBC) counts were also considered. In results, serum hsCRP levels were significantly higher in acutely agitated patients with schizophrenia than in healthy subjects. The elevation of serum hsCRP in patients was not affected by gender, family history (P>0.05), and clinical classification of schizophrenia (P>0.05). However, the elevation of hsCRP was suppressed by the medical treatment for schizophrenia with acute agitation (P<0.05). In addition, WBC counts, another inflammation-related indicator, were also increased significantly in acutely agitated patients compared with healthy subjects, consistent with the elevation of serum hsCRP. In conclusion, hsCRP is an important indicator of immune alterations in the pathogenesis of schizophrenia and has potential to be developed into a sensitive marker for the acute agitation in schizophrenia.

Chronic Peripheral Inflammation is Associated With Cognitive Impairment in Schizophrenia: Results From the Multicentric FACE-SZ Dataset

OBJECTIVES

Inflammation, measured by abnormal blood C-reactive protein (CRP) level, has been described in schizophrenia (SZ), being inconsistently related to impaired cognitive functions. The aim of the present study is to investigate cognitive impairment associated with abnormal CRP levels in a large multi-centric sample of community-dwelling SZ patients, using a comprehensive neuropsychological battery.

METHOD

Three hundred sixty-nine community-dwelling stable SZ subjects (76.2% men, mean age 32.7 y) were included and tested with a comprehensive battery of neuropsychological tests. Abnormal CRP level was defined as >3mg/L.

RESULTS

Multiple factor analysis revealed that abnormal CRP levels, found in 104 patients (28.2%), were associated with impaired General Intellectual Ability and Abstract Reasoning (aOR = 0.56, 95% CI 0.35-0.90, P = .014), independently of age, sex, education level, psychotic symptomatology, treatments, and addiction comorbidities. Abnormal CRP levels were also associated with the decline of all components of working memory (respectively effect size [ES] = 0.25, P = .033; ES = 0.27, P = .04; ES = 0.33, P = .006; and ES = 0.38, P = .004) and a wide range of other impaired cognitive functions, including memory (ES = 0.26, P = .026), learning abilities (ES = 0.28, P = .035), semantic memory (ES = 0.26, P = .026), mental flexibility (ES = 0.26, P = .044), visual attention (ES = 0.23, P = .004) and speed of processing (ES = 0.23, P = .043).

CONCLUSION

Our results suggest that abnormal CRP level is associated with cognitive impairment in SZ. Evaluating the effectiveness of neuroprotective anti-inflammatory strategies is needed in order to prevent cognitive impairment in SZ.

A significant causal association between C-reactive protein levels and schizophrenia

Many observational studies have shown elevated blood CRP levels in schizophrenia compared with controls, and one population-based prospective study has reported that elevated plasma CRP levels were associated with late- and very-late-onset schizophrenia. Furthermore, several clinical studies have reported the efficacy of anti-inflammatory drugs on the symptoms in patients with schizophrenia. However, whether elevated CRP levels are causally related to schizophrenia is not still established because of confounding factors and reverse causality. In the present study, we demonstrated that serum CRP levels were significantly higher in patients with schizophrenia than in the controls by conducting a case-control study and a meta-analysis of case-control studies between schizophrenia and serum CRP levels. Furthermore, we provided evidence for a causal association between elevated CRP levels and increased schizophrenia risk by conducting a Mendelian randomization analysis. Our findings suggest that elevated CRP itself may be a causal risk factor for schizophrenia.