Elevated lipids are associated with reduced regional brain structure in youth with bipolar disorder

Association among abnormal glycolipids, reproductive hormones, and cognitive dysfunction in female patients with bipolar disorder

BACKGROUND

Patients with bipolar disorder (BD) show abnormalities in glucolipid metabolism and reproductive hormone levels, which are of concern in women with BD. This study was dedicated to investigating the glucolipid and reproductive hormone levels of female patients, and to preliminarily investigating their relationships with cognition.

METHODS

A total of 58 unmedicated female BD patients, 61 stable-medicated female BD patients, and 63 healthy controls (HC) were recruited in this study. Serum glycolipid indexes and reproductive hormones were measured. Cognitive function was assessed using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the Stroop Color-Word Test (Stroop test).

RESULTS

Patients with BD showed significant cognitive impairment (p < 0.05), which was not affected by medication. Triglycerides (TG), luteinizing hormone (LH), and high-density lipoprotein cholesterol (HDL-c) were altered in stable-medicated BD patients. In addition, regression analysis showed that progesterone (PRGE) and prolactin (PRL) were negatively associated with cognitive performance in stable-medicated BD patients.

CONCLUSIONS

Female BD patients may have cognitive deficits and abnormal levels of glycolipids and reproductive hormones. And abnormal levels of glycolipids and reproductive hormones may be associated with cognitive dysfunction in female BD patients.

Associations of Triglycerides and Atherogenic Index of Plasma with Brain Structure in the Middle-Aged and Elderly Adults

Triglyceride (TG) and atherogenic index of plasma (AIP) have been acknowledged to be risk factors for vascular insults, but their impacts on the brain system remain elusive. To fill in some gaps, we investigated associations of TG and AIP with brain structure, leveraging the UK Biobank database. TG and high-density lipoprotein cholesterol (HDL-C) were examined at baseline and AIP was calculated as log (TG/HDL-C). We build several linear regression models to estimate associations of TG and AIP with volumes of brain grey matter phenotypes. Significant inverse associations of TG and AIP with volumes of specific subcortical traits were observed, among which TG and AIP were most significantly associated with caudate nucleus (TG: β [95% confidence interval CI] = -0.036 [-0.051, -0.022], AIP: -0.038 [-0.053, -0.023]), thalamus (-0.029 [-0.042, -0.017], -0.032 [-0.045, -0.019]). Higher TG and AIP were also considerably related with reduced cortical structure volumes, where two most significant associations of TG and AIP were with insula (TG: -0.035 [-0.048, -0.022], AIP: -0.038 [-0.052, -0.025]), superior temporal gyrus (-0.030 [-0.043, -0.017], -0.033 [-0.047, -0.020]). Modification effects of sex and regular physical activity on the associations were discovered as well. Our findings show adverse associations of TG and AIP with grey matter volumes, which has essential public health implications for early prevention in neurodegenerative diseases.

Association between triglyceride glucose index (TyG) and psychotic symptoms in patients with first-episode drug-naïve major depressive disorder

Objective

Major depressive disorder (MDD) sufferers frequently have psychotic symptoms, yet the underlying triggers remain elusive. Prior research suggests a link between insulin resistance (IR) and increased occurrence of psychotic symptoms. Hence, this study sought to investigate the potential association between psychotic symptoms in Chinese patients experiencing their first-episode drug-naïve (FEDN) MDD and the triglyceride glucose (TyG) index, an alternative measure of insulin resistance (IR).

Methods

Between September 2016 and December 2018, 1,718 FEDN MDD patients with an average age of 34.9 ± 12.4 years were recruited for this cross-sectional study at the First Hospital of Shanxi Medical University in China. The study collected clinical and demographic data and included assessments of anxiety, depression, and psychotic symptoms using the 14-item Hamilton Anxiety Rating Scale (HAMA), the 17-item Hamilton Depression Rating Scale (HAMD-17), and the positive subscales of the Positive and Negative Syndrome Scale (PANSS), respectively. Measurements of metabolic parameters, fasting blood glucose (FBG), and thyroid hormones were also gathered. To assess the correlation between the TyG index and the likelihood of psychotic symptoms, the study used multivariable binary logistic regression analysis. Additionally, two-segmented linear regression models were employed to investigate possible threshold effects in case non-linearity relationships were identified.

Results

Among the patients, 9.95% (171 out of 1,718) exhibited psychotic symptoms. Multivariable logistic regression analysis showed a positive correlation between the TyG index and the likelihood of psychotic symptoms (OR = 2.12, 95% CI: 1.21-3.74, P = 0.01) after adjusting for confounding variables. Moreover, smoothed plots revealed a nonlinear relationship with the TyG index, revealing an inflection point at 8.42. Interestingly, no significant link was observed to the left of the inflection point (OR = 0.50, 95% CI: 0.04-6.64, P = 0.60), whereas beyond this point, a positive correlation emerged between the TyG index and psychotic symptoms (OR = 2.42, 95% CI: 1.31-4.48, P = 0.01). Particularly, a considerable 142% rise in the probability of experiencing psychotic symptoms was found with each incremental elevation in the TyG index.

Conclusions

Understanding the non-linear link between the TyG index and the risk of psychotic symptoms in Chinese patients with FEDN MDD highlights the potential for targeted therapeutic approaches. By acknowledging the threshold effect observed, there is an opportunity to mitigate risk factors associated with IR-related psychiatric comorbidities through tailored interventions. These preliminary results stress the need for further longitudinal research to solidify these insights and contribute to more effective therapeutic strategies.

Comparing the metabolic pathways of different clinical phases of bipolar disorder through metabolomics studies

This study identified the metabolic biomarkers for different clinical phases of bipolar disorder (BD) through metabolomics. BD patients were divided into three groups: patients with BD and depressive episodes (BE, n = 59), patients with BD and mania/hypomania episodes (BH, n = 16), patients with BD and mixed episodes (BM, n = 10), and healthy controls (HC, n = 10). Serum from participants was collected for metabolomic sequencing, biomarkers from each group were screened separately by partial least squares analysis, and metabolic pathways connected to the biomarkers were identified. Compared with the controls, 3-D-hydroxyacetic acid and N-acetyl-glycoprotein showed significant differences in the BE, BH, and BM groups. This study suggests that different clinical types of BD share the same metabolic pathways, such as pyruvate, glycolysis/gluconeogenesis, and ketone body metabolisms. In particular, abnormal glycine, serine, and threonine metabolism was specific to BM; β-glucose, glycerol, lipids, lactate, and acetoacetate metabolites were specific to depressive episodes; the guanidine acetic acid metabolites specific to BH; and the acetic and ascorbic acids were metabolites specific to manic and BM. We screened potential biomarkers for different clinical phases of BD, which aids in BD typing and provides a theoretical basis for exploring the molecular mechanisms of BD.

White matter microstructural integrity is associated with retinal vascular caliber in adolescents with bipolar disorder

OBJECTIVE

Reduced white matter integrity is observed in bipolar disorder (BD), and is associated with cardiovascular risk in adults. This topic is underexplored in youth, and in BD, where novel microvascular measures may help to inform understanding of the vascular-brain connection. We therefore examined the association of retinal vascular caliber with white matter integrity in a cross-sectional sample of adolescents with and without BD.

METHODS

Eighty-four adolescents (n = 42 BD, n = 42 controls) completed retinal imaging, yielding arteriolar and venular caliber. Diffusion tensor imaging measured white matter fractional anisotropy (FA). Multiple linear regression tested associations between retinal vascular caliber and FA in regions-of-interest; corpus callosum, anterior thalamic radiation, uncinate fasciculus, and superior longitudinal fasciculus. Complementary voxel-wise analyses were performed.

RESULTS

Arteriolar caliber was elevated in adolescents with BD relative to controls (F(1,79) = 6.15, p = 0.02, η2p = 0.07). In the overall sample, higher venular caliber was significantly associated with lower corpus callosum FA (β = -0.24, puncorrected = 0.04). In voxel-wise analyses, higher arteriolar caliber was significantly associated with lower corpus callosum and forceps minor FA in the overall sample (β = -0.46, p = 0.03). A significant diagnosis-by-venular caliber interaction on FA was noted in 5 clusters including the right retrolenticular internal capsule (β = 0.72, p = 0.03), corticospinal tract (β = 0.72, p = 0.04), and anterior corona radiata (β = 0.63, p = 0.04). In each instance, venular caliber was more positively associated with FA in BD vs. controls.

CONCLUSION

Retinal microvascular measures are associated with white matter integrity in BD, particularly in the corpus callosum. This study was proof-of-concept, designed to guide future studies focused on the vascular-brain interface in BD.

Causal associations between blood lipids and brain structures: a Mendelian randomization study

The potential causal association between dyslipidemia and brain structures remains unclear. Therefore, this study aimed to investigate whether circulating lipids are causally associated with brain structure alterations using Mendelian randomization analysis. Genome-wide association study summary statistics of blood lipids and brain structures were obtained from publicly available databases. Inverse-variance weighted method was used as the primary method to assess causality. In addition, four additional Mendelian randomization methods (MR-Egger, weighted median, simple mode, and weighted mode) were applied to supplement inverse-variance weighted. Furthermore, Cochrane's Q test, MR-Egger intercept test, MR-PRESSO global test, and leave-one-out analysis were performed for sensitivity analyses. After Bonferroni corrections, two causal associations were finally identified: elevated non-high-density lipoprotein cholesterol level leads to higher average cortical thickness (β = 0.0066 mm, 95% confidence interval: 0.0045-0.0087 mm, P = 0.001); and elevated high-density lipoprotein cholesterol level leads to higher inferior temporal surface area (β = 18.6077 mm2, 95% confidence interval: 11.9835-25.2320 mm2, P = 0.005). Four additional Mendelian randomization methods indicated parallel results. Sensitivity tests demonstrated the stability. Overall, the present study showed causal relationships between several lipid profiles and specific brain structures, providing new insights into the link between dyslipidemia and neurological disorders.

Lipid Biomarker Research in Bipolar Disorder: A Scoping Review of Trends, Challenges, and Future Directions

Bipolar disorder (BD) is a disabling disorder with heterogeneous symptom profiles and trajectories. Like many other neuropsychiatric disorders, clinical decision making related to diagnoses and choice of treatment is based on clinical assessments alone, and risk prediction for treatment success or resistance at an individual level remains sparse. An enormous effort to add biological markers to this risk prediction is ongoing. The role of lipids in normal brain functioning is well established, and several hypotheses about the role of lipids in the pathogenesis of neuropsychiatric disorders, including BD, have been made. The frequent comorbidity between neuropsychiatric disorders and cardiovascular disease, the genetic overlap of risk genes for severe mental disorders and genes involved in lipid regulation, and the lipid-altering effects of antipsychotics and mood stabilizers indicate that lipids could hold promise as biomarkers for neuropsychiatric disorders, including BD. To date, reviews of lipid biomarkers in schizophrenia and major depression have noted caveats for future investigations, while reviews of lipid biomarker research in BD is missing. In the current scoping review, we present a comprehensive overview of trends in previous research on lipid biomarkers in BD. The current literature varies greatly in the phenotypes investigated and study designs, leading to divergent findings. Small sample size; potential confounders related to physical activity, nutritional status, and medication use; and cross-sectional designs were frequently reported limitations. Future research may benefit from pivoting toward utilization of newer laboratory techniques such as lipidomics, but consistent use of study methods across cohorts is also needed.

Lipid Metabolism Disorder in Cerebrospinal Fluid Related to Parkinson's Disease

BACKGROUND

Abnormal accumulation of lipids is found in dopamine neurons and resident microglia in the substantia nigra of patients with Parkinson's disease (PD). The accumulation of lipids is an important risk factor for PD. Previous studies have mainly focussed on lipid metabolism in peripheral blood, but little attention has been given to cerebrospinal fluid (CSF). We drew the lipidomic signature in CSF from PD patients and evaluated the role of lipids in CSF as biomarkers for PD diagnosis.

METHODS

Based on lipidomic approaches, we investigated and compared lipid metabolism in CSF from PD patients and healthy controls without dyslipidaemia in peripheral blood and explored the relationship of lipids between CSF and serum by Pearson correlation analysis.

RESULTS

A total of 231 lipid species were detected and classified into 13 families in the CSF. The lipid families, including phosphatidylcholine (PC), sphingomyelin (SM) and cholesterol ester (CE), had significantly increased expression compared with the control. Hierarchical clustering was performed to distinguish PD patients based on the significantly changed expression of 34 lipid species. Unsupervised and supervised methods were used to refine this classification. A total of 12 lipid species, including 3-hydroxy-dodecanoyl-carnitine, Cer(d18:1/24:1), CE(20:4), CE(22:6), PC(14:0/18:2), PC(O-18:3/20:2), PC(O-20:2/24:3), SM(d18:0/16:0), SM(d18:2/14:0), SM(d18:2/24:1), SM(d18:1/20:1) and SM(d18:1/12:0), were selected to draw the lipidomic signature of PD. Correlation analysis was performed and showed that the CE family and CE (22:6) in CSF had a positive association with total cholesterol in the peripheral blood from PD patients but not from healthy controls.

CONCLUSIONS

Our results revealed that the lipidomic signature in CSF may be considered a potential biomarker for PD diagnosis, and increased CE, PC and SM in CSF may reveal pathological changes in PD patients, such as blood-brain barrier leakage.

Differential association of endothelial function with brain structure in youth with versus without bipolar disorder

BACKGROUND

Mood symptoms and disorders are associated with impaired endothelial function, a marker of early atherosclerosis. Given the increased vascular burden and neurostructural differences among individuals with mood disorders, we investigated the endothelial function and brain structure interface in relation to youth bipolar disorder (BD).

METHODS

This cross-sectional case-controlled study included 115 youth, ages 13-20 years (n = 66 BD; n = 49 controls [CG]). Cortical thickness and volume for regions of interest (ROI; insular cortex, ventrolateral prefrontal cortex [vlPFC], temporal lobe) were acquired from FreeSurfer processed T1-weighted MRI images. Endothelial function was assessed using pulse amplitude tonometry, yielding a reactive hyperemia index (RHI). ROI and vertex-wise analyses controlling for age, sex, obesity, and intracranial volume investigated for RHI-neurostructural associations, and RHI-by-diagnosis interactions.

RESULTS

In ROI analyses, higher RHI (i.e., better endothelial function) was associated with lower thickness in the insular cortex (β = -0.19, p_FDR = 0.03), vlPFC (β = -0.30, p_FDR = 0.003), and temporal lobe (β = -0.22, p_FDR = 0.01); and lower temporal lobe volume (β = -0.16, p_FDR = 0.01) in the overall sample. In vertex-wise analyses, higher RHI was associated with lower cortical thickness and volume in the insular cortex, prefrontal cortex (e.g., vlPFC), and temporal lobe. Additionally, higher RHI was associated with lower vlPFC and temporal lobe volume to a greater extent in youth with BD vs. CG.

CONCLUSIONS

Better endothelial function was associated with lower regional brain thickness and volume, contrasting the hypothesized associations. Additionally, we found evidence that this pattern was exaggerated in youth with BD. Future studies examining the direction of the observed associations and underlying mechanisms are warranted.

Demographic, clinical and biochemical correlates of the length of stay for different polarities in Chinese inpatients with bipolar disorder: A real-world study

Introduction: Many patients with bipolar disorder (BD) need hospitalization, while the number of hospital beds for these patients is limited. Managing the length of stay (LOS) is an effective solution to this issue. Research on LOS and its influencing factors in BD is limited in China. This study aimed to identify the factors relevant to LOS in different polarities in Chinese patients with BD. Method: This was a real-world, cross-sectional study. Data were obtained from the electronic medical record system. Patients admitted to Beijing Anding Hospital between Jan 2014 and Dec 2017 and diagnosed with BD were included. Demographic information, clinical characteristics, and biochemical variables were collected. Patients were classified into short and long LOS groups based on a cutoff value. A univariate study and a multivariate logistic regression analysis were performed to identify variables related to LOS in various BD polarities. The receiver operating characteristic (ROC) analysis was utilized to evaluate the discrimination accuracy of the regression model. Result: Four thousand six hundred and seventy-five visits from 4,451 individuals were included in the analysis. For the whole sample, unmarried status, psychotic features, and family history of mental disorders were positively associated with long LOS (all p < 0.05). There was an additive interaction between a family history of mental disorders and polarities (p < 0.05). For manic episodes, unmarried status, psychotic features, and family history of mental disorders were positively associated with long LOS (all p < 0.05). For depressive episodes, psychotic features and high-density lipoprotein cholesterol (HDLC) levels were positively associated with long LOS (all p < 0.05). For mixed states, unmarried status was positively associated with long LOS, while low-density lipoprotein cholesterol (LDLC) levels were negatively associated with LOS (all p < 0.05). The area under the curve (AUC) values for depressive episodes, manic episodes, and mixed states in the combined model were 0.587, 0.553, and 0.619, respectively (all p < 0.05). Discussion: The findings suggested that LOS correlates differed by polarity, with marital status, psychotic features, a family history of mental disorders, and lipid levels strongly linked with LOS in patients with BD.

Neurovascular correlates of retinal microvascular caliber in adolescent bipolar disorder

BACKGROUND

The connection between vascular and brain metrics is well-studied in older adults, but neglected in youth and in psychiatric populations at increased cardiovascular risk. We therefore examined the association of retinal vascular caliber with cerebral blood flow (CBF) in adolescents with and without bipolar disorder (BD).

METHODS

Ninety-four adolescents (n = 48 BD, n = 46 controls) completed retinal fundus imaging, yielding estimates of arteriolar and venular diameter. Arterial spin labelling MRI was performed to measure CBF. We tested for associations between retinal vascular caliber and CBF in regions of interest; anterior cingulate cortex (ACC), middle frontal gyrus, and hippocampus in BD and controls separately. Complementary voxel-wise analyses were also performed.

RESULTS

In the BD group, higher arteriovenous ratio (AVR) was associated with greater ACC CBF (β = 0.34, p_uncorrected = 0.02), after controlling for age, sex, and BMI, however this finding did not survive correction for multiple comparisons. The control group did not show any associations (β = 0.13, p_uncorrected = 0.40). Voxel-wise analyses within the BD group detected a significant positive association between AVR and regional CBF in two distinct clusters: i) left hippocampus (p < 0.0001); ii) right middle temporal gyrus (p = 0.04).

LIMITATIONS

Limited sample size; young, medically healthy sample limits signal detection; cross-sectional design.

CONCLUSION

This study reveals that higher AVR is associated with higher regional CBF in adolescents with BD. Present findings advance understanding of potential neurofunctional mechanisms linking retinal vascular caliber with psychiatric diagnoses. This proof-of-concept study was designed to generate initial insights to guide future studies focusing on the vascular-brain connection in youth and in psychiatry.

Cerebral Blood Flow and Core Mood Symptoms in Youth Bipolar Disorder: Evidence for Region-Symptom Specificity

OBJECTIVE

Building on prior findings in adults, this study investigated regional cerebral blood flow (CBF) in relation to DSM-5 criterion A symptoms of depression and mania in youth with bipolar disorder (BD).

METHOD

The study recruited 81 youths with BD and 75 healthy controls 13-20 years old. CBF was ascertained using pseudocontinuous arterial spin labeling magnetic resonance imaging. Region-of-interest analyses examined the amygdala, anterior cingulate cortex (ACC), middle frontal gyrus, and global gray matter CBF. The association of criterion A depression and mania symptoms with CBF was examined dimensionally in youth with BD in regression analyses with continuous symptom severity scores. Age and sex were included as covariates. False discovery rate (FDR) was used to correct for 28 tests (4 regions by 7 symptoms; α < .0017). CBF for BD and healthy control groups was compared to give context for findings.

RESULTS

In youth with BD, depressed mood inversely correlated with ACC (β = -0.31, p_uncorrected = .004, p_FDR = .056) and global (β = -0.27, p_uncorrected = .013, p_FDR = .09) CBF. The same pattern was observed for anhedonia (ACC CBF: β = -0.33, p_uncorrected = .004, p_FDR = .056; global CBF: β = -0.29, p_uncorrected = .008, p_FDR = .07). There were no significant findings for manic symptoms or in BD vs healthy control contrasts.

CONCLUSION

The present findings, while not significant after correction for multiple testing, highlight the potential value of focusing on ACC in relation to depressed mood and anhedonia, and demonstrate that CBF is sensitive to depression symptom severity in youth. Lack of findings regarding manic symptoms may relate to the exclusion of fully manic participants in this outpatient sample.

Association of serum lipid levels with psychotic symptoms in young, first-episode and drug naïve outpatients with major depressive disorder: A large-scale cross-sectional study

BACKGROUND

Major depressive disorder (MDD) patients with psychotic symptoms have more complex clinical symptoms and higher relapse rates. The purpose of this study was to compare serum lipid differences between psychotic major depressive disorder (PMD) and non-psychotic major depressive disorder (NPMD) in a large sample of young first-episode drug naïve (FEDN) patients.

METHODS

We recruited 1289 young MDD patients. Socio-demographic information, clinical data, and lipid parameters were collected. The Hamilton Depression Rating Scale, the Hamilton Anxiety Rating Scale, and the positive symptom subscale of the Positive and Negative Syndrome Scale were used to assess patients' depressive, anxiety and psychotic symptoms, respectively.

RESULTS

Compared with the NPMD group, the PMD group had higher HAMD, HAMA scores, and higher TC, TG, and LDL-C levels. Correlation analysis showed that psychotic symptoms were significantly associated with the total score of HAMD and HAMA, and the levels of serum lipid. In addition, logistic regression analysis found that TC was associated with psychotic symptoms in young FEDN MDD patients.

CONCLUSION

Our results suggest TC levels may be associated with psychotic symptoms in young MDD patients. The importance of regular psychotic symptom assessment in young MDD patients with high TC levels should be taken into account.

Specific metabolic syndrome components predict cognition and social functioning in people with type 2 diabetes mellitus and severe mental disorders

OBJECTIVE

Obesity and metabolic diseases such as metabolic syndrome (MetS) are more prevalent in people with type 2 diabetes mellitus (T2DM), major depressive disorder (MDD), bipolar disorder (BD), and schizophrenia (SZ). MetS components might be associated with neurocognitive and functional impairments in these individuals. The predictive and discriminatory validity of MetS and its components regarding those outcomes were assessed from prospective and transdiagnostic perspectives.

METHODS

Metabolic syndrome components and neurocognitive and social functioning were assessed in 165 subjects, including 30 with SZ, 42 with BD, 35 with MDD, 30 with T2DM, and 28 healthy controls (HCs). A posteriori, individuals were classified into two groups. The MetS group consisted of those who met at least three of the following criteria: abdominal obesity (AO), elevated triglycerides (TG), reduced high-density lipoprotein cholesterol (HDL), elevated blood pressure (BP), and elevated fasting glucose (FPG); the remaining participants comprised the No-MetS group. Mixed one-way analysis of covariance and linear and binary logistic regression analyses were performed.

RESULTS

Cognitive impairment was significantly greater in the MetS group (n = 82) than in the No-MetS group (n = 83), with small effect sizes (p < 0.05; η²p = 0.02 - 0.03). In both groups, the most robust associations between MetS components and neurocognitive and social functioning were observed with TG and FPG (p < 0.05). There was also evidence for a significant relationship between cognition and BP in the MetS group (p < 0.05). The combination of TG, FPG, elevated systolic BP and HDL best classified individuals with greater cognitive impairment (p < 0.001), and TG was the most accurate (p < 0.0001).

CONCLUSIONS

Specific MetS components are significantly associated with cognitive impairment across somatic and psychiatric disorders. Our findings provide further evidence on the summative effect of MetS components to predict cognition and social functioning and allow the identification of individuals with worse outcomes. Transdiagnostic, lifestyle-based therapeutic interventions targeted at that group hold the potential to improve health outcomes.

Metabolomic biomarkers related to non-suicidal self-injury in patients with bipolar disorder

BACKGROUND

Non-suicidal self-injury (NSSI) is an important symptom of bipolar disorder (BD) and other mental disorders and has attracted the attention of researchers lately. It is of great significance to study the characteristic markers of NSSI. Metabolomics is a relatively new field that can provide complementary insights into data obtained from genomic, transcriptomic, and proteomic analyses of psychiatric disorders. The aim of this study was to identify the metabolic pathways associated with BD with NSSI and assess important diagnostic and predictive indices of NSSI in BD.

METHOD

Nuclear magnetic resonance spectrometry was performed to evaluate the serum metabolic profiles of patients with BD with NSSI (n = 31), patients with BD without NSSI (n = 46), and healthy controls (n = 10). Data were analyzed using an Orthogonal Partial Least Square Discriminant Analysis and a t-test. Differential metabolites were identified (VIP > 1 and p < 0.05), and further analyzed using Metabo Analyst 3.0 to identify associated metabolic pathways.

RESULTS

Eight metabolites in the serum and two important metabolic pathways, the urea and glutamate metabolism cycles, were found to distinguish patients with BD with NSSI from healthy controls. Eight metabolites in the serum, glycine and serine metabolism pathway, and the glucose-alanine cycle were found to distinguish patients with BD without NSSI from healthy controls. Five metabolites in the serum and the purine metabolism pathway were found to distinguish patients with BD with NSSI from those with BD without NSSI.

CONCLUSIONS

Abnormalities in the urea cycle, glutamate metabolism, and purine metabolism played important roles in the pathogenesis of BD with NSSI.

Elevated atherogenic lipid profile in youth with bipolar disorder during euthymia and hypomanic/mixed but not depressive states

OBJECTIVE

Abnormal blood lipid levels are common in individuals with bipolar disorder (BD). Previous studies have revealed lipid-mood associations in adults with BD, but no data on this relationship is available in youth populations. This cross-sectional study examined the associations of lipid levels with mood states and symptoms in a cohort of youth with BD.

METHODS

Participants were youth with BD and healthy controls (HCs) between the ages of 13-20 years. We compared the levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), and TG/HDL-C ratio between 4 participant episode groups: BD-euthymic (n = 28), BD-depressed (n = 29) BD-hypomanic/mixed (n = 31), and HCs (n = 89). We also examined for dimensional associations of lipids with mania and depression scores in the overall BD group and within BD episode subgroups.

RESULTS

TG levels were significantly higher in the BD-euthymic group (p = 0.008, d = 0.59) and in the BD-mixed/hypomanic group (p = 0.03, d = 0.44) compared to the HC group. TG/HDL-C ratio was also higher in the BD-euthymic group compared to the HC group (p = 0.01, d = 0.51). No dimensional associations were found between lipids and mood symptom scores in the overall BD group. However, within the BD-mixed/hypomanic subgroup, higher mania scores were associated with higher TG (β = 0.42, p = 0.04), TG/HDL-C ratio (β = 0.59, p = 0.002), and lower HDL-C (β = 0.56 p = 0.002).

CONCLUSIONS

Youth with BD demonstrate atherogenic lipid profiles. Higher atherogenic lipids were associated with hypomanic but, contrasting adult BD studies, not depressive symptoms. Future prospective studies are warranted to evaluate the temporal association between lipids and mood among youth with BD.

Association of blood pressure with brain structure in youth with and without bipolar disorder

BACKGROUND

We previously found that blood pressure (BP) is elevated, and associated with poorer neurocognition, in youth with bipolar disorder (BD). While higher BP is associated with smaller brain structure in adults, studies have not examined this topic in BD or youth.

METHODS

Participants were 154 youth, ages 13-20 (n = 81 BD, n = 73 HC). Structural magnetic resonance imaging and diastolic (DBP), and systolic (SBP) pressure were obtained. Region of interest (ROI; anterior cingulate cortex [ACC], insular cortex, hippocampus) and vertex-wise analyses controlling for age, sex, body-mass-index, and intracranial volume investigated BP-neurostructural associations; a group-by-BP interaction was also assessed.

RESULTS

In ROI analyses, higher DBP in the overall sample was associated with smaller insular cortex area (β=-0.18 p = 0.007) and was associated with smaller ACC area to a significantly greater extent in HC vs. BD (β=-0.14 p = 0.015). In vertex-wise analyses, higher DBP and SBP were associated with smaller area and volume in the insular cortex, frontal, parietal, and temporal regions in the overall sample. Additionally, higher SBP was associated with greater thickness in temporal and parietal regions. Finally, higher SBP was associated with smaller area and volume in frontal, parietal, and temporal regions to a significantly greater extent in BD vs. HC.

LIMITATIONS

Cross-sectional design, single assessment of BP.

CONCLUSION

BP is associated with brain structure in youth, with variability related to structural phenotype (volume vs. thickness) and psychiatric diagnosis (BD vs. HC). Future studies evaluating temporality of these findings, and the association of BP changes on brain structure in youth, are warranted.

Investigation of systemic immune-inflammation index, neutrophil/high-density lipoprotein ratio, lymphocyte/high-density lipoprotein ratio, and monocyte/high-density lipoprotein ratio as indicators of inflammation in patients with schizophrenia and bipolar disorder

BACKGROUND

The systemic immune-inflammation index (SII), system inflammation response index (SIRI), neutrophil/high-density lipoprotein (HDL) ratio (NHR), lymphocyte/HDL ratio (LHR), monocyte/HDL ratio (MHR), and platelet/HDL ratio (PHR) have been recently investigated as new markers for inflammation. The purpose of this research is to use large-scale clinical data to discuss and compare the predictive ability of the SII, SIRI, NHR, LHR, MHR, and PHR in patients with schizophrenia (SCZ) and bipolar disorder (BD), to investigate potential biomarkers.

MATERIALS AND METHODS

In this retrospective, naturalistic, cross-sectional study, we collected the hematological parameter data of 13,329 patients with SCZ, 4,061 patients with BD manic episodes (BD-M), and 1,944 patients with BD depressive episodes (BD-D), and 5,810 healthy subjects served as the healthy control (HC) group. The differences in the SII, SIRI, NHR, LHR, MHR, and PHR were analyzed, and a receiver operating characteristic (ROC) curve was used to analyze the diagnostic potential of these parameters.

RESULTS

Compared with the HC group, the values of the SII, SIRI, NHR, LHR, MHR, and PHR and the levels of neutrophils, monocytes, and triglycerides (TG) were higher in SCZ and BD groups, and levels of platelets, cholesterol (CHO), HDL, low-density lipoprotein (LDL), and apoprotein B (Apo B) were lower in SCZ and BD groups. Compared to the BD group, the values of the SIRI, lymphocytes, monocytes, and HDL were lower and the values of the SII, NHR, PHR, and platelet were higher in the SCZ group. In contrast to the BD-D group, the values of the SII; SIRI; NHR; and MHR; and levels of neutrophils, monocytes, and platelets were higher in the BD-M group, and the levels of CHO, TG, LDL, and Apo B were lower in the BD-M group. The MHR and NHR were predictors for differentiating the SCZ group from the HC group; the SIRI, NHR, and MHR were predictors for differentiating the BD-M group from the HC group; and the MHR was a predictor for differentiating the BD-D group from the HC group. The combination model of the indicators improved diagnostic effectiveness.

CONCLUSION

Our study highlights the role of systemic inflammation in the pathophysiology of SCZ, BD-M, and BD-D, the association between inflammation and lipid metabolism, and these inflammation and lipid metabolism indicators showed different variation patterns in SCZ, BD-D, and BD-M.