Neutrophil-lymphocyte and platelet-lymphocyte ratios among adolescents with bipolar disorder: A preliminary study

Inflammatory and oxidative stress biomarkers in children and adolescents with bipolar disorder - A systematic review and meta-analysis

Evidence suggests a role for low-grade inflammation and oxidative stress in the pathophysiology of bipolar disorder. We conducted a systematic review and meta-analysis of peripheral markers of inflammation and oxidative stress in children and adolescents under 20 years of age with bipolar disorder. We searched PubMed, Embase and psycINFO and performed random effects meta-analysis calculating standardized mean differences (SMD) of marker levels between patients with bipolar disorder and healthy control individuals. Ten studies comprising a total of 418 patients with bipolar disorder and 3017 healthy control individuals were included. The levels of C-Reactive Protein were higher in patients with bipolar disorder compared with healthy individuals (SMD 0.53; 95 %CI: 0.33-0.74; I2 = 0 %). For other biomarkers there were no statistically significant differences between groups. Findings were limited by a low number of studies and participants and methodological issues in the included studies. More and larger studies using rigorous methodology are needed to establish the role of inflammation and oxidative stress in children and adolescents with bipolar disorder.

Inflammatory Hematological Ratios in Adolescents with Mental Disorders: A Scoping Review

BACKGOUND

Inflammatory hematological ratios (IHRs), such as neutrophil to lymphocyte, monocyte to lymphocyte, and platelet to lymphocyte ratios, are associated with mental disorders, symptoms severity, and the disease phase. Evidence from the studies in adult patients has been summarized in systematic reviews and meta-analyses. The results of the studies in adolescents remain poorly systematized.

AIM

To summarize the findings from the studies that investigated the relationship of IHRs with mental disorders in adolescent patients.

METHODS

This scoping review included studies of IHRs in patients aged 10-19 years with mental disorders (other than anorexia nervosa), published in English by December 31, 2023. The search for relevant papers was performed in MEDLINE. The studies were categorized into two groups: studies with external controls (healthy adolescents) and studies with internal controls (patients in different phases of mental disorder, with or without self-harm/suicidal behaviors).

RESULTS

A total of 11 studies were included in the review (all cross-sectional ones). The results of these studies demonstrate that 1) adolescents with mental disorders (major depressive disorder, psychotic disorders, obsessive-compulsive disorder, attention deficit hyperactivity disorder, substance use disorders) have higher IHR values than individuals of the same age without corresponding disorders (5 studies); 2) IHR values are positively correlated with the severity of psychopathological symptoms (1 study); 3) higher IHR values are associated with the phase of the mental disorder - manic episode in bipolar disorder (1 study) and exacerbation of psychosis in psychotic disorders (1 study); and 4) higher IHR values are associated with self-harm/suicidal behaviors - suicide attempts (1 study) and non-suicidal self-injury (1 study).

CONCLUSION

IHRs are associated with mental disorders in adolescents, and higher IHR values are associated with a more severe/acute clinical presentation (severity of symptoms, mania, acute psychosis, self-harm/suicidal behaviors). Further studies of higher methodological quality are needed to evaluate the diagnostic and prognostic value of IHRs as biomarkers of mental disorders in adolescence.

Using the Bayesian variational spike and slab model in a genome-wide association study for finding associated loci with bipolar disorder

OBJECTIVE

The genome-wide association studies (GWAS) analysis, the most successful technique for discovering disease-related genetic variation, has some statistical concerns, including multiple testing, the correlation among variants (single-nucleotide polymorphisms) based on linkage disequilibrium and omitting the important variants when fitting the model with just one variant. To eliminate these problems in a small sample-size study, we used a sparse Bayesian learning model for finding bipolar disorder (BD) genetic variants.

METHODS

This study used the Wellcome Trust Case Control Consortium data set, including 1998 BD cases and 1500 control samples, and after quality control, 380,628 variants were analysed. In this GWAS, a Bayesian logistic model with hierarchical shrinkage spike and slab priors was used, with all variants considered simultaneously in one model. In order to decrease the computational burden, an alternative inferential method, Bayesian variational inference, has been used.

RESULTS

Thirteen variants were selected as associated with BD. The three of them (rs7572953, rs1378850 and rs4148944) were reported in previous GWAS. Eight of which were related to hemogram parameters, such as lymphocyte percentage, plateletcrit and haemoglobin concentration. Among selected related genes, GABPA, ELF3 and JAM2 were enriched in the platelet-derived growth factor pathway. These three genes, along with APP, ARL8A, CDH23 and GPR37L1, could be differential diagnostic variants for BD.

CONCLUSIONS

By reducing the statistical restrictions of GWAS analysis, the application of the Bayesian variational spike and slab models can offer insight into the genetic link with BD even with a small sample size. To uncover related variations with other traits, this model needs to be further examined.

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.

Neutrophil-lymphocyte ratios as inflammatory biomarkers in psychiatric patients

PURPOSE

There is a growing amount of evidence to suggest that inflammation may have a role in the onset and prognosis of psychiatric disorders. We reviewed the literature of studies investigating neutrophil-lymphocyte ratios (NLR), a biomarker of inflammation, in both adult and youth psychiatric populations. The limitations of NLR, in addition to the potential mechanisms underlying its relationship with psychiatric disorders, are also discussed.

RECENT FINDINGS

Unlike in the general population, NLR is elevated in a proportion of adult patients with schizophrenia, major depressive disorder and bipolar disorder, though associations with symptom severity and other clinical parameters are less clear. When compared to baseline, reductions in NLR are sometimes reported after treatment and remission. Results in youth populations largely resemble findings obtained from adult samples, even though youth studies are far fewer in number.

SUMMARY

The consistent findings of elevated NLR across the reviewed psychiatric disorders suggest that abnormal NLR is not specific to any one disorder but may reflect a pathological brain process that leads to brain dysfunction. These findings support hypotheses of neuroinflammation being important to the etiology of psychiatric disorders. More research is needed to further elucidate the relationship between specific diagnostic and behavioural constructs and NLR. Future work is also needed to determine the specific neuroinflammatory mechanisms that give rise to specific disorders.

Kronik psikiyatri hastalarında inflamasyon: nötrofil/lenfosit, platelet/lenfosit oranları ve ortalama trombosit hacmi

Objective: The aim of this study was to examine the Neutrophil/Lymphocyte Ratio(NLR), Platelet/Lymphocyte Ratios(PLR), and Mean Platelet Volume(MPV), red blood cell distribution width(RDW) and leukocyte cell levels of patients with Axis-I psychiatric disease by comparing them with each other and healthy controls. Material and Methods: A total of 600 people were included in our study, 500 of whom were taken as the patient and 100 as the control group. The diagnosis of patients according to DSM-5-Criteria were 34.8% Schizophrenia, 21% had Generalized-Anxiety-Disorder, 14.4% had Bipolar-Affective-Disorder, 14% had Major-Depressive-Disorder, 7.2% had Adjustment-Disorder, 4.2% had Schizoaffective-Disorder, 3.6% had other psychiatric illnesses. Results: It was seen that hemoglobin, platelet, monocyte, blood platelet distribution (PCT), percentage account of RDW (RDW-CV) did not have statistically significant differences between groups (p values were 0.082, 0.214, 0.526, 0.082, 0.771, respectively). The lymphocyte, eosinophil, basophil, MPV, standard deviation of RDW (RDW-SD) were higher compared with healthy controls (p values were 0.002, 0.003,

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.

Neutrophil/lymphocyte, platelet/lymphocyte and monocyte/lymphocyte ratios in mood disorders

Major depressive disorder (MDD) and bipolar disorders (BDs), the most severe types of mood disorders (MDs), are considered as among the most disabling illnesses worldwide. Several studies suggested that inflammatory neuroinflammation might be involved in the pathophysiology of MDs, while reporting increasing data on the relationships between these processes and classical neurotransmitters, hypothalamus-pituitary-adrenal axis (HPA), and neurotrophic factors. The assessment of neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) and monocyte/lymphocyte ratio (MLR) in peripheral blood represents a simple method to evaluate the inflammatory status. The aim of the present paper was to review the literature on the possible relationships between NLR, PLR and MLR in MDs, and to comment on their possible wider use in clinical research. Thirty-five studies were included in the present review. The majority of them higher values of these parameters, particularly NLR values, in patients with MDs, when compared to healthy subjects. The increase would appear more robust in patients with BD during a manic episode, thus indicating that it could be considered as both state and trait markers. In addition, increased NLR and PLR levels seem to represent prognostic elements for the early discovery of post-stroke depression. The findings of the present review would indicate the need to carry our further studies in this field. In particular, NLR, PLR and MLR seem to be promising tools to detect economically and easily the activation of the inflammatory system, and to perhaps evaluate the etiology and course of MDs. Again, they could suggest some information to better understand the relationship between inflammatory and cardiovascular disease and MDs, and thus, to provide clinical implications in terms of management and treatment.

Elevated neutrophil-to-lymphocyte ratio in children and adolescents with attention-deficit/hyperactivity disorder

OBJECTIVE

Inflammation is reported to play a substantial role in the pathophysiology of attention-deficit/hyperactivity disorder (ADHD). Neutrophil/lymphocyte ratio (NLR) and platelet/lymphocyte ratio (PLR) are inexpensive and potentially interesting biomarkers of inflammation. In this cross-sectional and retrospective study, we investigated the relationship between NLR, PLR and ADHD.

METHODS

This study consisted of 100 children and adolescents with ADHD (85 of those receiving psychopharmacological treatment), and 99 physically and mentally healthy children.

RESULTS

The mean NLR and PLR were significantly higher in patients than in controls. There was no significant difference between patients who received psychopharmacological treatment for ADHD and patient that did not with regard to NLR and PLR. No associations were found between NLR and PLR and ADHD symptom severity. The significance of NLR is not influenced by medication use, age and sex.

CONCLUSIONS

Our findings suggest that NLR and PLR may be inflammation biomarkers in children and adolescents with ADHD. Moreover, the significance of NLR is not influenced by medication use, age and sex. Prospective studies that address alterations in NLR and PLR and other pro-inflammatory cytokines following ADHD treatment may provide additional information about the inflammatory mechanisms in ADHD.Key pointsThe mean NLR and PLR were significantly higher in patients than in controls.The significance of NLR is not influenced by medication use, age and sex.No associations were found between NLR and PLR and ADHD symptom severity.Prospective studies that address alterations in NLR and PLR and other pro-inflammatory cytokines following psychopharmacological treatment of ADHD may provide additional information about the inflammatory mechanisms in ADHD.

Increased prolidase activity and high blood monocyte counts in pediatric bipolar disorder

Various psychological, genetic, and biochemical factors are thought to be involved in the aetiology of pediatric bipolar disorder (PBD). However, few studies have evaluated the biochemical basis of PBD. The level of peripheral blood mononuclear cells and serum prolidase activity were determined in PBD and matched healthy comparison subjects. Blood from 38 (age range: 14-17) PBD-type I and 37 age- and gender-matched healthy comparison subjects was analyzed for numbers of neutrophils, lymphocytes, monocytes, lymphocyte-to-monocyte ratio (LMR), neutrophil-to-lymphocyte ratio (NLR) and serum prolidase activity. The prolidase activity and monocyte count were significantly higher in PBD than the control group. There were no significant differences in numbers of neutrophils, lymphocytes, LMR and NLR between the patient and control groups. These results suggest that the immune system and prolidase activity may be activated in PBD. There is a clinical benefit from the early detection of PBD using serum prolidase activity levels and monocyte counts. Especially, prolidase activity may be a trait marker for diagnosing PBD. However, further studies are needed to verify these findings.