Elevated Platelet Parameter in First-Episode Schizophrenia Patients: A Cross-Sectional Study

Correlation analysis of peripheral platelet markers and disease phenotypes in Alzheimer's disease

INTRODUCTION

Platelets serve as the primary peripheral reservoir of amyloid beta (Aβ). However, there is limited research on platelet markers in routine blood examinations, particularly with regard to the large platelet ratio (P-LCR) in Alzheimer's disease (AD).

METHODS

This study included 512 AD patients and 205 healthy controls (HCs). Platelet markers and apolipoprotein E (APOE) 4 status were assessed in all participants.

RESULTS

The study revealed that P-LCR was significantly elevated in AD patients compared to HCs. In AD patients carrying APOE4, P-LCR significantly negatively correlated with Montreal Cognitive Assessment scores. There was an observed increasing trend in the rate of change in P-LCR with disease progression. Binary logistic regression analysis indicated that P-LCR may constitute a risk factor for AD, after adjusting for age, sex, APOE4, and body mass index.

DISCUSSION

P-LCR is associated with disease severity in AD patients carrying APOE4. P-LCR may be a promising marker to reflect platelet activity in AD patients.

HIGHLIGHTS

P-LCR significantly negatively correlated with MoCA scores in AD patients with APOE4. The rate of change in P-LCR showed an increasing trend with disease progression. P-LCR may be a risk factor for AD.

New role of platelets in schizophrenia: predicting drug response

Background

Elevated platelet count (PLTc) is associated with first-episode schizophrenia and adverse outcomes in individuals with precursory psychosis. However, the impact of antipsychotic medications on PLTc and its association with symptom improvement remain unclear.

Aims

We aimed to investigate changes in PLTc levels following antipsychotic treatment and assess whether PLTc can predict antipsychotic responses and metabolic changes after accounting for other related variables.

Methods

A total of 2985 patients with schizophrenia were randomised into seven groups. Each group received one of seven antipsychotic treatments and was assessed at 2, 4 and 6 weeks. Clinical symptoms were evaluated using the positive and negative syndrome scale (PANSS). Additionally, we measured blood cell counts and metabolic parameters, such as blood lipids. Repeated measures analysis of variance was used to examine the effect of antipsychotics on PLTc changes, while structural equation modelling was used to assess the predictive value of PLTc on PANSS changes.

Results

PLTc significantly increased in patients treated with aripiprazole (F=6.00, p=0.003), ziprasidone (F=7.10, p<0.001) and haloperidol (F=3.59, p=0.029). It exhibited a positive association with white blood cell count and metabolic indicators. Higher baseline PLTc was observed in non-responders, particularly in those defined by the PANSS-negative subscale. In the structural equation model, PLTc, white blood cell count and a latent metabolic variable predicted the rate of change in the PANSS-negative subscale scores. Moreover, higher baseline PLTc was observed in individuals with less metabolic change, although this association was no longer significant after accounting for baseline metabolic values.

Conclusions

Platelet parameters, specifically PLTc, are influenced by antipsychotic treatment and could potentially elevate the risk of venous thromboembolism in patients with schizophrenia. Elevated PLTc levels and associated factors may impede symptom improvement by promoting inflammation. Given PLTc's easy measurement and clinical relevance, it warrants increased attention from psychiatrists.

Trial registration number

ChiCTR-TRC-10000934.

Hematological and inflammatory markers in Han Chinese patients with drug-free schizophrenia: relationship with symptom severity

Background

There is a growing amount of evidence suggesting that immunity and inflammation play an important role in the pathophysiology of schizophrenia. In this study, we aimed to examine the relationship between hematological and inflammatory markers with symptom severity in Han Chinese patients with drug-free schizophrenia.

Methods

This retrospective study was conducted at Chaohu Hospital of Anhui Medical University and data were extracted from the electronic medical record system over a 5-year period (May 2017 to April 2022), including participants' general and clinical information as well as Brief Psychiatric Rating Scale (BPRS) scores and hematological parameters.

Results

A total of 2,899 patients with schizophrenia were identified through the initial search. After screening, 91 patients and 141 healthy controls (HCs) were included. The patients had a higher value of neutrophils/lymphocytes ratio (NLR), monocyte/lymphocyte ratio (MLR), and platelet/lymphocyte ratio (PLR) than HCs (all P < 0.001). MLR was positively correlated with BPRS total score (r = 0.337, P = 0.001) and resistance subscale score (r = 0.350, P = 0.001). Binary logistic regression analyses revealed that severely ill was significantly associated with being male and a higher value of MLR (Natural Logaruthm, Ln) (all P < 0.05), and the receiver operating characteristic (ROC) analysis showed good performance of a regression model with an area under the curve (AUC) value of 0.787.

Conclusion

Patients with drug-free schizophrenia have an unbalanced distribution of peripheral blood granulocytes, and elevated NLR, MLR and PLR. Patients with higher value of MLR tend to have more psychotic symptoms, especially those symptoms of hostility, uncooperativeness, and suspiciousness. Our study gives a preliminary indication that MLR is a potential predictor of disease severity in patients with drug-free schizophrenia.

Meta-analysis of peripheral mean platelet volume in patients with mental disorders: Comparisons in depression, anxiety, bipolar disorder, and schizophrenia

BACKGROUND

There is a growing interest in the role of immune and inflammatory responses in mental disorders (MDs). Mean platelet volume (MPV) is an extensively utilized hemogram parameter that reflects systemic inflammation and immune function. Our research sought to determine whether a connection exists between MPV and various types of MDs.

METHODS

We searched PubMed, EMBASE, PsychINFO, and Web of Science for eligible studies from inception to 15 February 2023, supplemented by manual searching the references from relevant articles. We applied standardized mean difference (SMD) and its 95% confidence interval (CI) to estimate the differences in MPV values in patients with MDs compared to controls.

RESULTS

We analyzed data from 24 surveys with 4843 participants (2450 patients with MDs and 2393 healthy controls). Two-step meta-analyses were conducted to estimate the SMD in MPV value between individuals with and without MDs. Higher MPV values were substantially linked to MDs (i.e., depression, anxiety, bipolar disorder, and schizophrenia). Moderator and stratified analyses revealed that the aggregate effects were more robust in specific populations, such as younger patients and those who had not taken antipsychotic medication within the previous month.

CONCLUSIONS

Our findings corroborate the role of inflammatory response in the pathogenesis of MDs and the pharmacological treatment of these conditions. Regarding the considerable heterogeneity among studies, the level of evidence was very low to moderate.

Comparison of frontal QRS-T angle and inflammatory parameters between the patients with drug-naive first episode psychosis and healthy controls

BACKGROUND

Frontal QRS-T (fQRS-T) angle is a novel marker to predict many cardiovascular diseases. The present study aims to compare the fQRS-T angle of first episode psychosis (FEP) patients and healthy controls (HC) and evaluate the relationship between fQRS-T angle and blood count-related inflammatory markers such as neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), and monocyte to high-density lipoprotein cholesterol ratio (MHR).

METHODS

Electrocardiogram (ECG) and complete blood count (CBC) of 63 patients who were diagnosed with drug-naive FEP in the psychiatry clinic of a training and research hospital and 78 healthy controls (HC) individuals who had applied to the health committee polyclinic for recruitment or pre-military examination between 2016 and 2021 were included.

RESULTS

fQRS-T angle was wider in FEP patients (55.5o) than in healthy controls (22o) (p < .001). NLR, PLR, and MHR were higher in FEP patients than in healthy controls (p = .001, p < .001, and p < .001, respectively). fQRS-T angle was positively correlated with NLR (r = 0.52 and p < .001) and MHR (r = 0.39 and p = .002) in FEP patients. NLR (t = 2.196 and p = .032) and MHR (t = 5.469 and p < .001) values were found to be the predictors of fQRS-T angle in FEP patients.

CONCLUSION

In summary, we can conclude that patients with FEP tend to exhibit a wider fQRS-T angle compared to their healthy controls. Additionally, the values of NLR and MHR could potentially serve as useful indicators for predicting the fQRS-T angle in FEP patients. Conducting subsequent long-term studies could provide deeper insights into the interpretation of the fQRS-T angle and its potential connection to cardiovascular diseases in schizophrenia patients.

Microglia and Other Cellular Mediators of Immunological Dysfunction in Schizophrenia: A Narrative Synthesis of Clinical Findings

Schizophrenia is a complex psychiatric condition that may involve immune system dysregulation. Since most putative disease mechanisms in schizophrenia have been derived from genetic association studies and fluid-based molecular analyses, this review aims to summarize the emerging evidence on clinical correlates to immune system dysfunction in this psychiatric disorder. We conclude this review by attempting to develop a unifying hypothesis regarding the relative contributions of microglia and various immune cell populations to the development of schizophrenia. This may provide important translational insights that can become useful for addressing the multifaceted clinical presentation of schizophrenia.

Mean platelet volume, platelet count, and neutrophil/lymphocyte ratio in drug-naïve patients with schizophrenia: a cross-sectional study

Introduction

Mean platelet volume (MPV), platelet count, and neutrophil/lymphocyte ratio (NLR) have been proposed to be biomarkers of the chronic inflammatory process in schizophrenia and indicative of increased cardiovascular risk.

Objective

To describe MPV, total platelet count (PLT), and NLR between healthy controls and patients with schizophrenia to determine the correlation between these parameters and the duration of untreated psychosis (DUP).

Methods

In a retrospective cross-sectional study, we included 175 patients with schizophrenia who had never received psychiatric treatment, and who had undergone blood biometry and blood chemistry within 24 h of admission. Laboratory studies were determined by the impedance method on Coulter ac-T 5 diff hematological equipment.

Results

Mean platelet volume levels in patients with schizophrenia were higher than in healthy controls but not statistically significant. The receiver operating characteristic curve for this parameter shows that the optimal cutoff point of agreement was 8.95 fL, with sensitivity and specificity for schizophrenia of 52% and 67%, respectively, and the area under the curve (AUC) was 0.580 (p = 0.079). DUP had no significant correlation with the blood parameters analyzed.

Conclusion

The results partially support the hypothesis that MPV, platelet count, and NLR is related to schizophrenia, and further research is needed to establish whether there is an underlying chronic inflammatory process.

The Predictive Value of Monocyte/High-Density Lipoprotein Ratio (MHR) and Positive Symptom Scores for Aggression in Patients with Schizophrenia

Background and Objectives: Schizophrenia with aggression often has an inflammatory abnormality. The monocyte/high-density lipoprotein ratio (MHR), neutrophil/high-density lipoprotein ratio (NHR), platelet/high-density lipoprotein ratio (PHR) and lymphocyte/high-density lipoprotein ratio (LHR) have lately been examined as novel markers for the inflammatory response. The objective of this study was to assess the relationship between these new inflammatory biomarkers and aggression in schizophrenia patients. Materials and Methods: We enrolled 214 schizophrenia inpatients in our cross-sectional analysis. They were divided into the aggressive group (n = 94) and the non-aggressive group (n = 120) according to the Modified Overt Aggression Scale (MOAS). The severity of schizophrenia was assessed using the Positive and Negative Syndrome Scale (PANSS). The numbers of platelets (PLT), neutrophils (NEU), lymphocytes (LYM), monocytes (MON) and the high-density lipoprotein (HDL) content from subjects were recorded. The NHR, PHR, MHR and LHR were calculated. We analyzed the differences between those indexes in these two groups, and further searched for the correlation between inflammatory markers and aggression. Results: Patients with aggression had higher positive symptom scores (p = 0.002). The values of PLT, MON, MHR and PHR in the aggressive group were considerably higher (p < 0.05). The NHR (r = 0.289, p < 0.01), LHR (r = 0.213, p < 0.05) and MHR (r = 0.238, p < 0.05) values of aggressive schizophrenia patients were positively correlated with the total weighted scores of the MOAS. A higher MHR (β = 1.529, OR = 4.616, p = 0.026) and positive symptom scores (β = 0.071, OR = 1.047, p = 0.007) were significant predictors of aggression in schizophrenia patients. Conclusions: The MHR and the positive symptom scores may be predictors of aggressive behavior in schizophrenia patients. The MHR, a cheap and simple test, may be useful as a clinical tool for risk stratification, and it may direct doctors’ prevention and treatment plans in the course of ordinary clinical care.

The correlation between neutrophil-to-lymphocyte ratio, carcinoembryonic antigen, and carbohydrate antigen 153 levels with chemotherapy-related cognitive impairment in early-stage breast cancer patients

Background

The changes in inflammation and tumor biomarkers are associated with the anti-tumor immunological processes. Early detection and intervention are of great significance to the clinical management of cancer-related diseases. Peripheral blood biomarkers [e.g., neutrophil-to-lymphocyte ratio (NLR), carcinoembryonic antigen (CEA), and carbohydrate antigen 153 (CA153)] are obtained in real-timely, conveniently, and less invasively, and proved to availably predicted the disease states and prognosis of various cancers, including breast cancer (BC). Inflammation and poor disease management promote cognitive impairment. Chemotherapy-related cognitive impairment (CRCI) hazard long-term survival and quality of life (QOL) of BC patients, but its correlation with NLR, CEA, and CA153 is not clear.

Purpose

This study aimed to investigate changes in NLR, CEA, and CA153 levels before and after chemotherapy and their correlation with CRCI in patients with early-stage BC.

Materials and methods

The 187 patients with BC who were measured for NLR, CEA, and CA153 values within the first 24 hours of admission, were assigned into two groups: the before/after chemotherapy group (BCG/ACG). The ACG was assigned into two subgroups based on the cognitive assessment results: the cognitive normal/impaired group (CNG/CIG). Patients’ self-perceived cognitive impairments were evaluated using a mini-mental state examination (MMSE), prospective and retrospective memory (PM and RM) questionnaire (PRMQ), and functional assessment of cancer therapy-cognitive function version 3 (FACT-Cog, version 3, including CogPCI, CogOth, CogPCA, and CogQOL). Their QOL was also evaluated.

Results

The NLR and CA153 levels were elevated after chemotherapy (BCG vs ACG: Z = −1.996 and −1.615, P = 0.046 and 0.106, respectively), and significantly elevated in patients with CRCI (BCG vs CIG: Z = −2.444 and -2.293, P = 0.015 and 0.022; respectively). However, there was not reach significant difference in CEA levels between the four groups. In addition, there was a weak to moderate correlation between peripheral blood biomarkers (NLR, CEA, and CA153) levels and CRCI (r = −0.404, −0.205, −0.322; respectively; P < 0.001). Cognitive impairment scores (MMSE, PM, RM, and FACT-Cog) had a strong correlation with QOL in patients with early-stage BC (r = −0.786, 0.851, 0.849, and 0.938; respectively; P < 0.001).

Conclusion

NLR and CA153 m be valuable diagnostic adjuncts of CRCI, and CRCI has a strong correlation with QOL in patients with early-stage BC.

Neutrophil-to-lymphocyte ratio (NLR) variations in relationship with childhood maltreatment in patients with anorexia nervosa: a retrospective cohort study

PURPOSE

Anorexia nervosa (AN) is a serious mental illness. It is frequently accompanied by a history of childhood maltreatment (CM) that may constitute a specific ecophenotype in patients with eating disorders necessitating special assessment and management. This retrospective study tested whether in patients with AN, CM-related chronic stress may manifest through low-grade inflammation reflected by an increase in white blood cell ratios (neutrophil-to-lymphocyte ratio, NLR, platelet-to-lymphocyte ratio, and monocyte-to-lymphocyte ratio).

METHODS

Participants (N = 206) were enrolled at an eating disorder daycare unit in Montpellier, France, from March 2013 and January 2020. CM was assessed using the childhood trauma questionnaire (CTQ). The Eating Disorder Examination Questionnaire (EDE-Q) and the MINI were used to assess AN severity and the other clinical characteristics, respectively.

RESULTS

NLR was higher in patients with AN and history of CM (p = 0.029) and in patients with AN and history of emotional abuse (p = 0.021), compared with patients with AN without history of CM. In multivariate analysis, emotional abuse (β = 0.17; p = 0.027) contributed significantly to NLR variability.

CONCLUSION

In patients with AN, NLR is a low-grade inflammation marker that is influenced by various sociodemographic, clinical and biological factors. It is more directly affected by some CM types, especially emotional abuse, than by the presence/absence of CM history. Future studies should focus on mediators between CM and increased inflammation, such as interoceptive awareness, emotional dysregulation, food addiction, and stress sensitization.

LEVEL OF EVIDENCE

III. Evidence obtained from well-designed cohort or case-control analytic studies.

Neutrophil/lymphocyte, platelet/lymphocyte and monocyte/lymphocyte ratios in patients with affective disorders

OBJECTIVE

There is substantial evidence to support that the alterations in the immune-inflammation system play a crucial role in the pathogenic mechanism of affective disorders. The neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) and monocyte/lymphocyte ratio (MLR) have been recently investigated as simple, rapid, and inexpensive inflammation markers. The purpose of the research is to use large-scale clinical data to study the difference of the inflammation ratios in first-episode MDD, recurrent MDD, BD depressive episodes and manic episode.

METHODS

A cross-sectional design was applied to retrospectively analyse the data that were extracted from electronic health records. A total of 16,174 Chinese affective disorder patients were enrolled in this study, and 6681 healthy subjects served as controls. The differences in the NLR, MLR, PLR and whole blood count data among different groups were compared, and the contributing factors for the occurrence of MDD and BD were analysed.

RESULTS

First-episode and recurrent MDD patients exhibited significantly elevated NLRs and MLRs compared to healthy controls. Compared with the MDD patients, the BD patients showed higher NLRs and MLRs and lower PLRs. Further analysis showed that the BD manic episode patients had significantly elevated NLRs and MLRs compared to patients with BD depressive episodes or MDD. MLR was a risk factor for the occurrence of MDD and that the NLR and MLR were risk factors for the occurrence of BD.

CONCLUSIONS

Our study highlights the role of systemic inflammation in the pathophysiology of MDD and BD, particularly during manic BD episodes.

Higher neutrophil-lymphocyte ratio is associated with depressive symptoms in Japanese general male population

Relationships between the neutrophil–lymphocyte ratio (NLR) and/or the platelet-lymphocyte ratio (PLR) and neuroinflammatory diseases have been reported. Depression is also associated with neuroinflammation. Here, we determined the association between the NLR, PLR, and depressive symptoms. This cross-sectional study is a secondary analysis of the data of the Iwaki Health Promotion Project 2017. We analyzed the characteristics and laboratory data of 1,015 Japanese subjects (597 females, 408 males) including their NLR and PLR values. We assigned the subjects with a Center for Epidemiologic Studies Depression Scale (CES-D) score ≥ 16 to the depressive symptoms group. We performed a multivariate logistic regression analysis to determine whether the NLR and/or PLR were associated with depressive symptoms (CES-D ≥ 16). Two hundred subjects (19.7%; 122 [20.4%] females, 78 [19.1%] males) were assigned to the depressive symptoms group. There were significant differences between the non-depressive symptoms and depressive symptoms groups in the NLR [median (25th to 75th percentile): 1.54 (1.24, 1.97) vs. 1.76 (1.32, 2.37), P = 0.005] and the PLR [median (25th to 75th percentile): 123.7 (102.0, 153.9) vs. 136.8 (107.0, 166.5), P = 0.047] in males, but not in females. The multivariate logistic regression analysis demonstrated that the NLR was significantly associated with depressive symptoms in males (adjusted odds ratio: per 1 increase, 1.570; 95% confidence interval: 1.120–2.220; P = 0.009). In conclusion, our findings indicate that higher NLR may be associated with depressive symptoms in males.

New Hematological Parameters as Inflammatory Biomarkers: Systemic Immune Inflammation Index, Platerethritis, and Platelet Distribution Width in Patients with Adult Attention Deficit Hyperactivity Disorder

OBJECTIVES

The potential role of neuroinflammation in adult attention deficit hyperactivity disorder (ADHD) patients has been investigated with peripheral hemogram-related inflammatory markers. Systemic immune inflammation index (SII) is defined as a new index that has been developed for the balance of inflammatory and immune status.

METHODS

Our study was based on a prospective routine complete blood count(CBC) analysis of 74 Adult ADHD patients and 70 healthy participants. The DSM-5-Clinician version and Barratt impulsivity scale-11 were used to evaluate the participants.

RESULTS

There was no statistical difference in the comparison of the SII ratios, platelet distribution width (PDW), and plateretritis (PCT) (p>0.05 for each) in a group of a young adults with ADHD and in a comparison control group. These inflammatory indicators were found to be similar between patients newly diagnosed with ADHD (n=40) and patients using methylphenidate (n=34) (p>0.05 for each). The relationship between ADHD clinical symptoms and severity and inflammation was evaluated. A significant negative correlation was observed between attention deficit scores and PCT (r=-0.301, p=0.009). A positive significant correlation was found between hyperactivity scores and SII (r=0.247, p=0.034). A significant positive correlation was found between Barrat motor scores and PDW(r=241, p=0.038). In the regression analysis, the PCT variable changed the attention deficit variable (β=.33, t(70)= -2.703, p=.009, pr ²= .094) predicted negatively and significantly.

CONCLUSIONS

We demonstrated the association of SII, which is independently associated with adverse outcomes in many diseases, and the severity of hyperactivity symptoms in adult ADHD. The fact that PCT predicts attention deficit negatively and decisively shows the importance of inflammatory assessments specific to clinical presentations. The critical importance of platelets in inflammatory processes in ADHD has been demonstrated once again with inflammatory markers such as SII, PLT, and PDW, which can be accessed by an easily applicable complete blood count method.

Characteristics of platelet-associated parameters and their predictive values in Chinese patients with affective disorders

OBJECTIVE

Platelets are increasingly considered to play an important role in inflammation and are being regarded as a putative bridge linking mental diseases and inflammatory response. Platelet-associated haematological parameters including mean platelet volume (MPV), platelet distribution width (PDW), plateletcrit (PCT), systemic immune-inflammation index (SII), platelet to lymphocyte ratio (PLR), platelet to albumin ratio (PAR) and red blood cell distribution width (RDW) to platelet ratio (RPR), have been recently investigated as simple, easily available, and inexpensive inflammatory markers. In this study, we aimed is to use large-scale clinical data to study platelet parameters in patients with affective disorders, to further investigate the predictive power of platelet parameters for major depressive disorder (MDD) and bipolar disorder (BD).

METHODS

The retrospective, naturalistic, cross-sectional study analysed the data of 14,007 Chinese affective disorder patients, including 4,801 patients with first-episode MDD, 4,098 patients with recurrent MDD, 3,444 patients with BD manic episodes and 1,664 patients with BD depressive episodes. Meanwhile, 6,847 healthy subjects were served as the control group. The differences in the MPV, PDW, PCT, SII, PLR, PAR, RPR and albumin among different groups were compared, and the contributing factors for the occurrence of MDD or BD were analysed.

RESULTS

There were significant differences in MPV, PDW, PCT, SII, PLR, RPR and albumin values among the study groups. In the subjects, patients experiencing BD manic episodes had the highest mean values of MPV and SII, patients experiencing BD depressive episodes had the lowest mean values of platelet counts and PAR, and patients with MDD had the highest mean values of PLR and RDW. The levels of MPV, PDW and albumin were independently correlated with MDD and BD, and they are important predictors for differentiating patients with MDD or BD from healthy controls.

CONCLUSIONS

Our study demonstrated that different affective disorders have unique platelet parameter variation patterns, highlighting the role of platelet parameters and systemic inflammation in the pathophysiology of MDD and BD.

Neutrophil-to-Lymphocyte Ratio, Platelet-to-Lymphocyte Ratio, and Monocyte-to-Lymphocyte Ratio in Depression: An Updated Systematic Review and Meta-Analysis

BACKGROUND

Research on neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR) in depression is still emerging and has increased 3-fold since the first meta-analysis. An updated meta-analysis with sufficient studies can provide more evidence for a potential relationship between NLR, PLR, MLR, and depression.

METHODS

We identified 18 studies from the PubMed, EMBASE, Cochrane library, and Web of Science databases. Meta-analyses were performed to generate pooled standardized mean differences (SMDs) and 95% confidence intervals (CIs) between patients with depression and controls. Sensitivity analysis, subgroup analysis, meta-regression, and publication bias were conducted.

RESULTS

A total of 18 studies including 2,264 depressed patients and 2,415 controls were included. Depressed patients had significantly higher NLR and PLR compared with controls (SMD = 0.33, 95% CI: 0.15-0.52, p < 0.001 and SMD = 0.24, 95% CI: 0.02-0.46, p < 0.05, respectively). MLR was slightly higher in depressed individuals compared to controls (SMD = 0.15, 95% CI: -0.26 to 0.55, p > 0.05), despite the absence of significance. Sensitivity analysis removing one study responsible for heterogeneity showed a higher and significant effect (SMD = 0.32, 95% CI: 0.20-0.44) of MLR. Three subgroup analyses of NLR, PLR, MLR, and depression revealed obvious differences in the inflammatory ratios between depressed patients and controls in China and the matched age and gender subgroup. Individuals with post-stroke depression (PSD) had higher NLR and MLR values as compared to non-PSD patients (SMD = 0.51, 95% CI: 0.36-0.67, p < 0.001 and SMD = 0.46, 95% CI: 0.12-0.79, p < 0.01, respectively). Meta-regression analyses showed that male proportion in the case group influenced the heterogeneity among studies that measured NLR values (p < 0.05).

CONCLUSIONS

Higher inflammatory ratios, especially NLR, were significantly associated with an increased risk of depression. In the subgroup of China and matched age and gender, NLR, PLR, and MLR were all elevated in depressed patients vs. controls. Individuals with PSD had higher NLR and MLR values as compared to non-PSD patients. Gender differences may have an effect on NLR values in patients with depression.

Relation Between Unconjugated Bilirubin and Peripheral Biomarkers of Inflammation Derived From Complete Blood Counts in Patients With Acute Stage of Schizophrenia

BACKGROUND

Inflammation and oxidative stress are the major leading hypothetical causes of schizophrenia. Unconjugated bilirubin (UCB) is an efficient endogenous plasma antioxidant. Inflammation is closely linked to oxidative stress. The relationship between UCB and inflammatory markers should be paid close attention in schizophrenia acute stage. In this paper, combined UCB and inflammatory markers were evaluated for their capability in predicting schizophrenia in the acute stage to find an easy and effective indicator to identify acute schizophrenia.

METHODS

A total of 6,937 acute schizophrenia patients and 6,404 healthy controls (HCs) were enrolled. UCB and peripheral biomarkers of inflammation derived from complete blood counts (CBC) were investigated in the subjects with acute schizophrenia, and the results were compared with HCs. Simultaneously, Spearman test was employed to assess the correlation between the variables, while logistic regression was adopted to determine the combined equation and receiver operating characteristic curve was used to evaluate the combined value of UCB and peripheral biomarkers of inflammation derived from CBC to predict schizophrenia in the acute stage.

RESULTS

The study indicates that white blood cells, neutrophil, monocyte, mean platelet volume (MPV), red cell distribution width (RDW), neutrophil/lymphocyte ratio (NLR), and monocyte/lymphocyte ratio (MLR) have significantly increased in schizophrenia (p < 0.05 for all), while platelet, lymphocyte, and platelet/lymphocyte ratio (PLR) in schizophrenia have significantly decreased (p < 0.05 for all). UCB exhibits negative correlation with MPV significantly (r = 0.121, p < 0.001), and no correlation with neutrophil and monocyte. The correlations between UCB and other peripheral biomarkers of inflammation derived from CBC are very weak. MPV, RDW, NLR, MLR, PLR, and UCB were taken as independent variables for a logistic regression analysis. The model was as follows: Logit  ( P 1 ) = - 6 . 141 + 0 . 827  MPV + 5 . 613  MLR - 0 . 005  PLR - 0 . 346  UBC . The combination demonstrates better effectiveness in predicting schizophrenia in the acute stage (AUC 0.831, 95% CI 0.825 to 0.837).

CONCLUSION

UCB has a protective effect on acute stage of schizophrenia, which is weak and indirect by affecting the proinflammatory processes. Our findings suggest that a combination of MLR, MPV, PLR, and UBC could be used to predict acute stage of schizophrenia.