Neuropsychiatric syndromes in lupus: prevalence using standardized definitions

Chorea associated with systemic lupus erythematosus- a systematic review

ObjectiveChorea is one of the 19 neuropsychiatric manifestations observed in systemic lupus erythematosus (SLE). This article reviews the literature to determine the prevalence and clinical and laboratory features associated with chorea in SLE.MethodsWe performed a literature review following the PRISMA guidelines and using the following MESH terms in the search and analysis: "Chorea", "movement disorders", "systemic lupus erythematosus", "SLE", "neuropsychiatric manifestations", "neuropsychiatric lupus (NPSLE)", with full articles in English, Portuguese, and Spanish, between September 1999 and January 2024, in PubMed and Scielo.Results13,922 patients from 60 cohort studies and 41 patients from 18 case/series reports were included. Chorea had a pooled prevalence of 1.1% in SLE patients. We found no association between chorea and clinical or immunological features reported in cohort studies. In case series and case reports, chorea occurred more frequently before or at SLE diagnosis and more frequently in childhood-onset SLE. We propose an investigation and treatment scheme based on the literature review.ConclusionChorea is a rare manifestation in SLE and factors associated with its occurrence have not been addressed in cohort studies.

Systemic lupus erythematosus: updated insights on the pathogenesis, diagnosis, prevention and therapeutics

Systemic lupus erythematosus (SLE) is a chronic inflammatory illness with heterogeneous clinical manifestations covering multiple organs. Diversified types of medications have been shown effective for alleviating SLE syndromes, ranging from cytokines, antibodies, hormones, molecular inhibitors or antagonists, to cell transfusion. Drugs developed for treating other diseases may benefit SLE patients, and agents established as SLE therapeutics may be SLE-inductive. Complexities regarding SLE therapeutics render it essential and urgent to identify the mechanisms-of-action and pivotal signaling axis driving SLE pathogenesis, and to establish innovative SLE-targeting approaches with desirable therapeutic outcome and safety. After introducing the research history of SLE and its epidemiology, we categorized primary determinants driving SLE pathogenesis by their mechanisms; combed through current knowledge on SLE diagnosis and grouped them by disease onset, activity and comorbidity; introduced the genetic, epigenetic, hormonal and environmental factors predisposing SLE; and comprehensively categorized preventive strategies and available SLE therapeutics according to their functioning mechanisms. In summary, we proposed three mechanisms with determinant roles on SLE initiation and progression, i.e., attenuating the immune system, restoring the cytokine microenvironment homeostasis, and rescuing the impaired debris clearance machinery; and provided updated insights on current understandings of SLE regarding its pathogenesis, diagnosis, prevention and therapeutics, which may open an innovative avenue in the fields of SLE management.

Systematic review of the reporting of extrarenal manifestations in observational studies of Saudi patients with systemic lupus erythematosus

BACKGROUND

SLE is prevalent in Saudi Arabia, with numerous studies focusing on SLE in adult patients. However, there is a lack of comprehensive studies summarising the extrarenal manifestations of SLE in this population. This study aims to assess the variability in the prevalence rates of extrarenal manifestations of SLE across different cities in Saudi Arabia and to emphasise the need for a national registry to better understand the overall disease burden in the region.

METHODS

We conducted a systematic review of articles with no time restrictions, including studies from databases such as Medline, ScienceDirect, EBSCO and PubMed up to July 2024. The review process involved screening, data extraction and quality assessment in duplicate. Only observational or experimental studies focusing on extrarenal manifestations in adult patients with SLE in Saudi Arabia were included. The review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist for systematic reviews to ensure a rigorous and comprehensive evaluation.

RESULTS

A total of 35 studies were included, primarily retrospective cohort studies. Riyadh showed the highest number of publications over time. Musculoskeletal involvement in SLE ranged from 2% to 100%, with most studies reporting 46%-85%. Mucocutaneous manifestations, including discoid rash (5%-100%), malar rash (up to 79%) and photosensitivity (6.12%-29.3%), varied widely. Raynaud's phenomenon was noted at 4.5%-15.2%. Constitutional symptoms were more common in early-onset SLE, while serositis and cardiopulmonary issues showed variability. Neuropsychiatric symptoms, especially depression, reached up to 67.6%.

CONCLUSION

This study explores the prevalence of extrarenal manifestations of SLE among adult Saudi patients, highlighting significant regional variability in musculoskeletal, dermatological, cardiovascular and neurological symptoms. It addresses a gap in the literature for a region where autoimmune diseases are a growing public health concern. The findings emphasise the need for population-based studies to investigate environmental, genetic and lifestyle factors influencing SLE progression.

Neurological Manifestations of Systemic Lupus Erythematosus: A Comprehensive Review

Neurological involvement in systemic lupus erythematosus (SLE) poses significant challenges, impacting patient morbidity, mortality, and quality of life. This narrative review provides an update on the pathogenesis, clinical presentation, diagnosis, and management of neurological SLE. The multifaceted pathophysiology involves immune-mediated and vascular mechanisms such as autoantibodies, neuroinflammation, complement dysregulation, and genetic factors. Neuropsychiatric SLE (NPSLE) manifests in a variety of ways, including cognitive dysfunction, mood disorders, psychosis, cerebrovascular disease, demyelinating syndromes, and neuropathies. Diagnosing neurological SLE is complicated by nonspecific and fluctuating symptoms, requiring comprehensive neurological examination, neuroimaging, autoantibody profiling, and cerebrospinal fluid analysis. Current management strategies include corticosteroids, immunosuppressive agents, and emerging biologics targeting specific immune pathways. Managing neuropsychiatric symptoms, seizures, and neuropathic pain remains a complex aspect of treatment. This review highlights the importance of early recognition and tailored management approaches to improve patient outcomes in neurological SLE.

Altered medial temporal lobe subregion volumes in systemic lupus erythematosus patients with neuropsychiatric symptoms

BACKGROUND

Systemic lupus erythematosus (SLE) often presents with neuropsychiatric (NP) involvement, including cognitive impairment and depression. Past magnetic resonance imaging (MRI) research in SLE patients showed smaller hippocampal volumes but did not investigate other medial temporal lobe (MTL) regions. Our study aims to compare MTL subregional volumes in SLE patients to healthy individuals (HI) and explore MTL subregional volumes in relation to neuropsychiatric SLE (NPSLE) manifestations.

METHODS

A total of 70 SLE patients and 25 HI underwent clinical evaluation, cognitive testing, and 3 tesla MRI imaging. T1-weighted MRI images were analyzed using the Automatic Segmentation of Hippocampal Subfields-T1 software. Analyses of Covariance were used to compare MTL subregion volumes between SLE and HI, and between NPSLE and non-NPSLE patients according to three models: the American College of Rheumatology (ACR) model defined by the ACR case definitions for NPSLE (n = 42), the more stringent Systemic Lupus International Collaborating Clinics (SLICC) B model (n = 21), and the most stringent SLICC A model (n = 15). Additionally, we explored the relation between MTL subregion volumes, cognitive functions, and depression scores in SLE patients using partial correlation analyses.

RESULTS

Significantly smaller volumes of bilateral whole hippocampus, anterior hippocampus, posterior hippocampus, and Brodmann Area 35 were demonstrated in NPSLE compared to non-NPSLE patients according to the ACR model (p = 0.01, p = 0.03, p = 0.04, and p = 0.01 respectively). The differences did not reach significance according to the SLICC B and SLICC A models. No significant differences in MTL subregional volumes between SLE patients and HI were found. Partial correlation analyses showed a significant positive correlation between left Brodmann Area 35 volume and complex attention scores in SLE patients. No significant associations between MTL subregion volumes and depression scores were demonstrated.

CONCLUSIONS

NPSLE patients display significantly smaller volumes in various subregions of the MTL compared to non-NPSLE patients. These findings are suggestive of neuronal damage in MTL subregions in NPSLE patients on a group level.

High throughput multiplex immunoassays stratify patients according to symptom burden across the anti-Ro positive systemic autoimmune rheumatic disease spectrum

Anti-Ro/SS-A antibodies are prevalent across systemic autoimmune rheumatic diseases (SARDs) and may signify a distinctive phenotype. This study aimed to identify protein biomarkers associated with symptom burden and health-related quality of life (HR-QoL), and use protein-based stratification to identify clinically meaningful clusters and inflammatory pathways implicated. Anti-Ro positive SARD patients were enrolled in a 6-month pilot study. HR-QoL was determined using a patient-reported visual analogue scale, and symptom burden was assessed with the EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI). Proximity extension immunoassays measured normalized protein expression (NPX) across 92 inflammatory proteins. Linear regression identified proteins linked to patient outcomes. Unsupervised hierarchical clustering of baseline NPX identified patient clusters. Functional protein association networks were visualized using String V.12.0. Diagnostic groups showed no differences in HR-QoL or physician global assessment (PhGA). Poor HR-QoL and high symptom burden correlated with downregulated inflammatory proteins, while PhGA correlated with upregulated proteins. Two distinct clusters were identified; Cluster 1, 'low expression cluster' exhibited higher symptom burden and more impaired HR-QoL, while Cluster 2, 'high expression cluster' correlated with a higher physician global assessment (PhGA). Key hub proteins included TGF-β1, CXCL-8, and CCL-2. This study identified patient clusters across the Ro-positive SARD, linking symptom burden to specific proteomic profiles. Unraveling novel protein networks associated with symptom burden and poor HR-QoL may identify therapeutic targets, which address patient-reported outcome measures (PROMs) across several disease indications.

Neurocognitive and Neuropsychiatric Implications of Fibrosing Interstitial Lung Diseases

Patients with interstitial lung diseases (ILDs) associate a large variety of comorbidities that have a significant impact on their clinical outcomes and survival. Among these comorbidities is neurological impairment. This review highlights what is known about the cognitive function, central nervous system (CNS), depression, and anxiety in patients with specific forms of fibrosing ILDs, such as idiopathic pulmonary fibrosis, sarcoidosis, hypersensitivity pneumonitis, connective tissue diseases, etc. The most common pathogenic mechanisms for neurocognitive dysfunction as well as the screening methods and tools for their identification are also described in this review.

Clinical Predictors of Mood Disorders and Prevalence of Neuropsychiatric Symptoms in Patients with Systemic Lupus Erythematosus

Background/Objectives: We aimed to determine the prevalence and clinical correlations of mood disorders in a sample of systemic lupus erythematosus (SLE) patients. Hence, we hypothesized that the prevalence of mood disorders would be lower than reported in the literature and that patients would remain clinically stable and show less damage accrual despite low-dose corticosteroid prescription. Methods: In total, 92 SLE outpatients gave informed consent to participate in this cross-sectional study. Psychiatric and autoimmune clinical data were obtained, and a structured psychiatric interview was performed. The main clinical scales for the assessment of clinical symptomatology were included. To examine the potential relationships of presenting a mood disorder in SLE, clinical correlations and multivariate analyses were performed. Results: Mood disorders were the most prevalent disorder reported by SLE patients (16%), followed by adjustment disorders (5%). A significant proportion of patients presented psychosocial disturbances that did not meet the ICD-10 criteria for psychiatric diagnosis. According to the cut-off criterion for the Montgomery-Åsberg Depression Rating Scale (MADRS), up to 27% of the sample met the clinical criteria for depression. The multivariate analysis revealed a relationship between the presence of a mood disorder with total scores of the MADRS and the Young Mania Rating Scale (YMRS). Conclusions: The prevalence of mood disorders in patients with SLE was lower than previously reported. Although self-report clinical scales are useful for assessing clinical symptomatology, they should not be used in place of a comprehensive standardized interview conducted by a trained mental health specialist. Multidisciplinary teamwork is required for the early identification and therapeutic management of autoimmune patients with neuropsychiatric disorders.

Central neurological manifestations in a sample of Syrian patients with systemic lupus erythematosus: cross-sectional study

Introduction

The authors aimed to study systemic lupus erythematosus (SLE) central neurological patterns and their correlations with the disease activity.

Patients and methods

The authors' retrospective observational study was carried out on admitted SLE patients. The patients' demographic data, clinical examinations, laboratory tests, imaging studies, and systemic lupus erythematosus disease activity index (SLEDAI) were recorded.

Results

Thirty-six SLE patients had neurological manifestations from 203 patients, but 8 patients were excluded. 90.2% were females. The age of neuro-lupus manifestation was 24.1+2.9 years. Neurological manifestations were the initial presentation in 25% of patients. General seizures were the frequent manifestation. SLEDAI was 29.51±18.43, while it was 18.3±9.2 among patients without neuropsychiatric systemic lupus erythematosus (NPSLE). Twenty-five percent of patients had pleocytosis on cerebrospinal fluid (CSF) analysis. Small lesions were seen in 57.1% of patients on brain MRIs, and large lesions were observed in 10.6%. These findings were compatible with the disease activity.

Discussion

Central nervous system involvement ranged between 10 and 80%, and much more with active disease. The frequent finding was general seizures. Psychosis and cognitive impairment were relatively frequent. Adult NPSLE manifestations had developed before or around the time of SLE diagnosis and within the first year after diagnosis. These manifestations were directly correlated to the disease activity. Abnormality in CSF is characterized by slight pleocytosis, and elevation of protein with normal fructose. MRI is the neuroimaging test of choice for NPSLE in clinical practice.

Conclusion

Central neurological involvement in SLE was seen early in the course of the disease, and correlating to the disease activity.

Audiovestibular Dysfunction in Systemic Lupus Erythematosus Patients: A Systematic Review

Audiovestibular dysfunction in patients with systemic lupus erythematosus has been underestimated for decades. Systemic lupus erythematosus can affect both the auditory and vestibular systems simultaneously. Several potential pathophysiological mechanisms behind systemic lupus erythematosus-related audiovestibular dysfunction have been proposed, including antibody-mediated immune responses, cell-mediated cytotoxicity, immune complex deposition in microvessels, central involvement in the audiovestibular pathway, and ototoxicity from medications used in systemic lupus erythematosus treatment. Currently available tests to evaluate audiovestibular function in systemic lupus erythematosus patients are neither specific nor sensitive. Nevertheless, there is no consensus regarding the efficacy of treatments for audiovestibular dysfunction in such patients. In this systematic review, we electronically searched the PubMed, Embase, ClinicalKey, Web of Science, and ScienceDirect platforms to find eligible articles. The first inspection date was on 29 December 2023 and the final update search date was on 11 June 2024. Further, we rated the quality of the included articles with Newcastle-Ottawa Scale. Based upon the aforementioned systematic review process, we have summarized the currently available evidence on the characteristics, pathophysiology, examination, and treatment of audiovestibular dysfunction related to systemic lupus erythematosus. Furthermore, we have proposed a specific steroid treatment protocol to manage audiovestibular dysfunction related to systemic lupus erythematosus. Audiovestibular dysfunction related to systemic lupus erythematosus may be responsive to adequate treatments, potentially allowing for reversibility if the disease is recognized and managed in a timely manner. Therefore, to provide clinically relevant evidence to clinicians, we have organized this literature review article to summarize the available evidence on the characteristics, pathophysiology, examination, and treatment of audiovestibular dysfunction in patients with systemic lupus erythematosus. Finally, based on our modified steroid treatment protocol, we would like to provide a new treatment strategy to clinicians to manage systemic lupus erythematosus-related audiovestibular dysfunction.

Evaluation of depressive and anxiety symptoms in childhood-onset systemic lupus erythematosus: Frequency, course, and associated risk factors

BACKGROUND

Depressive and anxiety symptoms are common in childhood-onset systemic lupus erythematosus (cSLE), yet their etiology and course remain unclear. We investigated the frequency of depressive and anxiety symptoms longitudinally in youth with cSLE, and associated socio-demographic and disease factors.

METHODS

Participants 8-18 years with cSLE completed baseline measures [demographic questionnaire, Center for Epidemiologic Studies Depression Scale for Children (CES-DC), Screen for Childhood Anxiety Related Disorders (SCARED), and psychiatric interview] and follow-up measures (CES-DC and SCARED) > 6 months later. Prevalence of clinically significant depressive (score >15 on CES-DC) or anxiety symptoms (score ≥25 on SCARED) was calculated at baseline and follow-up. Baseline psychiatric interview diagnoses were tabulated. Relationships between socio-demographics (neighborhood-level material deprivation, ethnic concentration, adverse childhood event history, psychiatric condition in a first-degree relative), disease-related factors (disease duration, major organ disease, disease activity, glucocorticoid use, comorbid medical condition) and baseline depressive and anxiety scores, were examined in linear regression models. Factors with univariate associations with p < 0.2 were included in multivariable adjusted models.

RESULTS

At baseline, of 51 participants with a mean disease duration of 4.3 years (SD 2.7), 35% (n = 18) and 35% (n = 18) had clinically significant depressive and anxiety symptoms, respectively. Anxiety disorder was diagnosed by psychiatric interview in 14% (n = 7), depressive disorders in 6% (n = 3), and post-traumatic stress disorder in 4% (n = 2). Adverse childhood events and first-degree relative with psychiatric condition were present in 40% (n = 20) and 37% (n = 18), respectively. In multivariable regression analysis, baseline depressive symptoms were positively correlated with neighbourhood-level material deprivation (β = 4.2, 95% CI [1.0, 7.3], p = 0.01) and psychiatric condition in a first-degree relative (β = 7.3, 95% CI [2.2, 12.4], p = 0.006). No associations were found between baseline anxiety scores and patient factors. At a median follow-up of 13.5 months (IQR 10.5, 18) for CES-DC (n = 34) and SCARED (n = 44), depressive and anxiety symptoms were persistent (18%, n = 6; 16%, n = 7), and newly present (24%, n = 8; 16% n = 7) at follow-up.

CONCLUSION

In this sample, depressive and anxiety symptoms were prevalent and persistent. Depressive symptoms correlated with neighborhood-level material deprivation, and family psychiatric history. These findings support routine psychosocial assessment in cSLE, and provision of appropriate resources.

The Sixth Sense: Self-nucleic acid sensing in the brain

Our innate immune system uses pattern recognition receptors (PRRs) as a first line of defense to detect microbial ligands and initiate an immune response. Viral nucleic acids are key ligands for the activation of many PRRs and the induction of downstream inflammatory and antiviral effects. Initially it was thought that endogenous (self) nucleic acids rarely activated these PRRs, however emerging evidence indicates that endogenous nucleic acids are able to activate host PRRs in homeostasis and disease. In fact, many regulatory mechanisms are in place to finely control and regulate sensing of self-nucleic acids by PRRs. Sensing of self-nucleic acids is particularly important in the brain, as perturbations to nucleic acid sensing commonly leads to neuropathology. This review will highlight the role of nucleic acid sensors in the brain, both in disease and homeostasis. We also indicate the source of endogenous stimulatory nucleic acids where known and summarize future directions for the study of this growing field.

Ectopic CD4+ T cells in choroid plexus mediate neuropsychiatric lupus symptoms in mice via interferon-γ induced microglia activation

Neuropsychiatric systemic lupus erythematosus (NPSLE) is a disabling and potentially life-threatening complication of SLE. This study aims to investigate whether ectopic CD4+ T cells in the choroid plexus mediate NPSLE in mice. Intracerebroventricular (ICV) injection of anti-CD4 antibody effectively depleted CP-resident CD4+ T cells and alleviated NPSLE-like symptoms in MRL/lpr mice. Following ICV injection, the majority of isolated lupus CD4+ T cells from donor MRL/lpr mice predominantly stayed in the CP for at least 28 days in recipient C57BL/6 mice, while nearly all isolated CD4+ T cells from MRL/MpJ mice disappeared within 7 days. ICV injection of lupus CD4+ T cells resulted in NPSLE-like symptoms, including impaired behavioral performances, increased microglial activation, and abnormal microstructure changes. Flow cytometry analysis revealed that the majority of isolated lupus CD4+ T cells were positive for IFN-γ. Neutralizing intracerebral IFN-γ alleviated NPSLE-like symptoms in MRL/lpr mice. Moreover, ICV injection of anti-IFN-γ antibody or microglial depletion by PLX3397 benefited most NPSLE-like symptoms in lupus CD4+ T-treated mice, while ICV injection of IFN-γ mimicked most NPSLE-like symptoms. In conclusion, CP-resident lupus CD4+ T cells contribute to NPSLE-like symptoms in mice via Interferon-γ induced microglia activation. Depleting CP-resident lupus CD4+ T cells, interferon-γ, or activated microglia may be potential therapeutic targets for NPSLE.

The clinical features and potential mechanisms of cognitive disorders in peripheral autoimmune and inflammatory diseases

According to a study from World Health Organization's Global Burden of Disease, mental and neurological disorders have accounted for 13% of global diseases in recent years and are on the rise. Neuropsychiatric conditions or neuroinflammatory disorders are linked by the presence of an exaggerated immune response both peripherally and in the central nervous system (CNS). Cognitive dysfunction (CD) encompasses a complex group of diseases and has frequently been described in the field of autoimmune diseases, especially in multiple non-CNS-related autoimmune diseases. Recent studies have provided various hypotheses regarding the occurrence of cognitive impairment in autoimmune diseases, including that abnormally activated immune cells can disrupt the integrity of the blood-brain barrier (BBB) to trigger a central neuroinflammatory response. When the BBB is intact, autoantibodies and pro-inflammatory molecules in peripheral circulation can enter the brain to activate microglia, inducing CNS inflammation and CD. However, the mechanisms explaining the association between the immune system and neural function and their contribution to diseases are uncertain. In this review, we used clinical statistics to illustrate the correlation between CD and autoimmune diseases that do not directly affect the CNS, summarized the clinical features and mechanisms by which autoimmune diseases trigger cognitive impairment, and explored existing knowledge regarding the link between CD and autoimmune diseases from the perspective of the field of neuroimmunology.

Functional Brain Network Alterations in Patients With Systemic Lupus Erythematosus With Different Cognitive Function States: A Graph Theory Analysis Study

OBJECTIVE

The study aimed to investigate the characteristics of brain functional network disruption in patients with systemic lupus erythematosus (SLE) with different cognitive function states by using graph theory analysis and to explore their relationship with clinical data and neuropsychiatric scales.

METHODS

Resting-state functional magnetic resonance imaging data were collected from 38 female SLE patients and 44 healthy controls. Based on Montreal Cognitive Assessment (MoCA) scores, SLE patients were divided into a high MoCA group (MoCA-H; MoCA score, ≥26) and a low MoCA group (MoCA-L; MoCA score, <26). The matrix of resting-state functional brain networks of subjects in the 3 groups was constructed by using the graph theory approach. The topological properties of the functional brain networks, including global and local metrics, in the 3 groups were calculated. The differences in the topological properties of networks between the 3 groups were compared. In addition, Spearman correlation analysis was used to explore the correlation between altered topological properties of brain networks and clinical indicators, as well as neuropsychiatric scales in SLE patients in the MoCA-L group.

RESULTS

At the global level, in the sparsity threshold range of 0.10 to 0.34, the values of small-world properties were greater than 1 in all 3 groups, indicating that functional brain networks of both 3 groups had small-world properties. There were statistically significant differences in the characteristic path length, global, and local efficiency between 3 groups ( F = 3.825, P = 0.0260; F = 3.722, P = 0.0285; and F = 3.457, P = 0.0364, respectively). Systemic lupus erythematosus patients in the MoCA-L group showed increased characteristic path length ( t = 2.816, P = 0.00651), decreased global ( t = -2.729, P = 0.00826), and local efficiency ( t = -2.623, P = 0.0109) compared with healthy controls. No statistically significant differences in local metrics were found between the MoCA-H group and the healthy control, MoCA-L groups. At the local level, there was statistically significant difference in the node efficiency among the 3 groups ( P < 0.05 after Bonferroni correction). Compared with healthy controls, SLE patients in the MoCA-L group showed decreased node efficiency in left anterior cingulate paracingulate gyrus, bilateral putamen, bilateral pallidum, and left Heschl gyrus. No statistically significant differences in the local metrics were found between the MoCA-H, MoCA-L, and healthy control groups. Correlation analysis in SLE patients in the MoCA-L group showed that the characteristic path length was positively correlated with C4 levels ( r = 0.587, P = 0.007), the global and local efficiencies were negatively correlated with C4 levels ( r = -0.599, P = 0.005; r = -0.599, P = 0.005, respectively), and the node efficiency in the bilateral putamen was negatively correlated with C4 levels ( r = -0.611, P = 0.004; r = -0.570, P = 0.009). The node efficiency in the left pallidum was negatively correlated with disease duration ( r = -0.480, P = 0.032). The node efficiency in the left Heschl gyrus was negatively correlated with IgM levels ( r = -0.478, P = 0.033). No correlation was noted between other network metrics, clinical indicators, and neuropsychological scales.

CONCLUSIONS

The topological properties of functional brain networks were disrupted in SLE patients with low MoCA scores, suggesting that altered topological properties of the brain networks were associated with cognitive function in SLE patients. Correlation between altered topological properties of the brain networks and clinical indicators was noted in SLE patients with low MoCA scores, suggesting that altered topological properties of brain networks in SLE patients may have clinical significance as imaging markers for monitoring disease changes in patients with SLE.

The impact of antiphospholipid antibodies/antiphospholipid syndrome on systemic lupus erythematosus

aPLs are a major determinant of the increased cardiovascular risk in patients with SLE. They adversely affect clinical manifestations, damage accrual and prognosis. Apart from the antibodies included in the 2006 revised classification criteria for APS, other non-classical aPLs might help in identifying SLE patients at increased risk of thrombotic events. The best studied are IgA anti-β2-glycoprotein I, anti-domain I β2-glycoprotein I and aPS-PT. Major organ involvement includes kidney and neuropsychiatric systems. aPL/APS severely impacts pregnancy outcomes. Due to increased thrombotic risk, these patients require aggressive cardiovascular risk factor control. Primary prophylaxis is based on low-dose aspirin in high-risk patients. Warfarin is the gold-standard drug for secondary prophylaxis.

What is known about the effects of vitamin D in neuropsychiatric lupus?

Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect several organs and systems. The central and/or peripheral nervous system can suffer from complications known as neuropsychiatric lupus (NPSLE). Studies have associated the manifestations of SLE or NPSLE with vitamin D deficiency. It has been shown that hypovitaminosis D can lead to cognition deficits and cerebral hypoperfusion in patients with NPSLE. In this review article, we will address the main features related to vitamin D supplementation or serum vitamin D levels with neuropsychiatric manifestations, either in patients or in animal models of NPSLE.

A nested case-control study investigating short-term prognosis, clinical and imaging features in acute ischemic stroke patients with systemic lupus erythematosus

OBJECTIVES

To investigate acute ischemic stroke (AIS) patients with systemic lupus erythematosus (SLE) clinical and imaging features, and to explore the impact of SLE on the short-term prognosis of AIS patients.

METHODS

A nested case-control study was conducted in The First Affiliated Hospital of Zhengzhou University between October 1, 2019, and May 31, 2021. The case group consisted of 28 AIS patients diagnosed with SLE, and 112 AIS patients without SLE were selected by incidence density sampling as a control group.

RESULTS

Among 140 patients, the mean age was (48.4 ± 15.6) years, and 130 (92.9%) were females. Higher levels in low-density lipoprotein cholesterol (LDL-C) (2.5 mmol/L vs. 2.1 mmol/L; P = 0.049), D-dimer (DDi) (0.7 mg/L vs. 0.3 mg/L; P = 0.02), and C-reactive protein (CRP) (13.2 mg/L vs. 6.3 mg/L; P = 0.002) were observed in the case group. On imaging, the case group was more prevalent in simultaneous involvement of the anterior and posterior circulation (42.9% vs. 17.0%; P = 0.004), multiple infarcts (46.4% vs. 20.5%; P = 0.008) and stroke of other undetermined etiologies (SUE) (28.6% vs. 6.3%; P = 0.002) than the control group. SLE (OR 5.94, 95%CI [1.04-34.39]; P = 0.045) was an independent risk factor for a poor short-term prognosis of AIS patients.

CONCLUSIONS

Higher levels of LDL-C, CRP, and DDi, multiple infarcts and simultaneous involvement of the anterior, and posterior circulation were more prevalent in the AIS patients with SLE. Further, SLE was also found as an independent risk factor for AIS patients' poor short-term prognosis.

MRI BrainAGE demonstrates increased brain aging in systemic lupus erythematosus patients

Introduction

Systemic lupus erythematosus (SLE) is an autoimmune connective tissue disease affecting multiple organs in the human body, including the central nervous system. Recently, an artificial intelligence method called BrainAGE (Brain Age Gap Estimation), defined as predicted age minus chronological age, has been developed to measure the deviation of brain aging from a healthy population using MRI. Our aim was to evaluate brain aging in SLE patients using a deep-learning BrainAGE model.

Methods

Seventy female patients with a clinical diagnosis of SLE and 24 healthy age-matched control females, were included in this post-hoc analysis of prospectively acquired data. All subjects had previously undergone a 3 T MRI acquisition, a neuropsychological evaluation and a measurement of neurofilament light protein in plasma (NfL). A BrainAGE model with a 3D convolutional neural network architecture, pre-trained on the 3D-T1 images of 1,295 healthy female subjects to predict their chronological age, was applied on the images of SLE patients and controls in order to compute the BrainAGE. SLE patients were divided into 2 groups according to the BrainAGE distribution (high vs. low BrainAGE).

Results

BrainAGE z-score was significantly higher in SLE patients than in controls (+0.6 [±1.1] vs. 0 [±1.0], p = 0.02). In SLE patients, high BrainAGE was associated with longer reaction times (p = 0.02), lower psychomotor speed (p = 0.001) and cognitive flexibility (p = 0.04), as well as with higher NfL after adjusting for age (p = 0.001).

Conclusion

Using a deep-learning BrainAGE model, we provide evidence of increased brain aging in SLE patients, which reflected neuronal damage and cognitive impairment.

Aseptic leptomeningitis induced by azathioprine in systemic lupus erythematosus: a rare manifestation

Systemic lupus erythematosus (SLE) is an autoimmune systemic disease and these patients can have neurological involvement; however, aseptic leptomeningitis is considered to be a very rare feature, observed in 1.4-2.0% of patients. Here, we described a case of a young male with SLE treated with azathioprine with progressive headache, which revealed diffuse posterior fossa leptomeningitis, relatively sparing the supratentorial compartment, that represent an adverse drug reaction - a rare manifestation of central nervous system involvement in SLE. Treatment with azathioprine was interrupted and methylprednisolone was initiated and the patient has significant improvement of his neurological state in 5 days later, demonstrating total involution of the leptomeningeal enhancement on MRI follow-up.

Prevalence of cognitive impairment and cognitive improvement in patients with systemic lupus erythematosus during a 6-month follow-up study

OBJECTIVES

The Montreal Cognitive Assessment (MoCA) is a simple and reliable screening tool for early detection for cognitive impairment in systemic lupus erythematosus (SLE). Most previous studies were cross-sectional with small samples. Research on long-term cognitive changes and reversibility is limited. This study aimed to establish the prevalence of cognitive impairment and changes in SLE patients after 6 months and the associated factors.

METHODS

A prospective study was conducted in 200 patients with SLE between April 2021 and March 2022. Demographic data, disease activity, and medications were recorded. MoCA was administered at baseline and 6 months; for Thais, scores 17-24 indicate mild cognitive impairment, while ≤16 signifies severe impairment. Multivariate analysis identified factors associated with cognitive impairment and improvement.

RESULTS

The patients' median age was 44 years (range: 19-73), 96% were female, and 55% had < 12 years of education. The median disease duration was 11 years (range: 0-51.8), and 79% of patients had inactive disease. Cognitive impairment was found in 70% of patients (mild, 63%; severe, 7%). The most often affected domains were delayed recall (82%), abstraction (80.5%), language (76%) and visuospatial/executive function (70.5%), whereas orientation and naming were the least involved. Factors significantly associated with cognitive impairment were age > 40 years (OR, 3.71; 95% CI, 1.72-8.00), formal education < 12 years (OR, 3.11; 95% CI, 1.45-6.63), and prednisolone use (OR, 2.21; 95% CI, 1.08-4.51). Sixty-six (38.2%) of 173 patients completing the 6-month re-evaluation exhibited cognitive changes (52 [30.1%] improved; 14 [8.1%] deteriorated). Except for delayed recall, all commonly affected domains showed significant improvement. Disease activity, prednisolone, antimalarials, or immunosuppressant use did not predict cognitive improvement.

CONCLUSIONS

Mild cognitive impairment is prevalent among patients with SLE. Due to the possibility of reversibility, early recognition and additional research to identify relevant factors are required.

Performance of eye sign combined with increased interleukin-6 in cerebrospinal fluid in patients with neuropsychiatric lupus erythematosus

OBJECTIVES

To ascertain whether microvascular alterations of eye sign combined with intrathecal concentrations of interleukin-6 (IL-6) can predict the development of neuropsychiatric systemic lupus erythematosus (NPSLE).

METHODS

Cerebrospinal fluid (CSF) and serum samples of IL-6 were collected and measured at the same time for patients with SLE who were consecutively enrolled. Patients with a diagnosis of NPSLE were identified. Eye sign examinations according to our criteria were performed and scored for all SLE patients. Demographic and clinical parameters were compared between groups to identify potential predictors for NPSLE using multivariable logistic regression analysis. The performance of potential predictors from eye sign along with IL-6 in the CSF was assessed.

RESULTS

A total of 120 patients with SLE were enrolled; 30 with NPSLE and 90 with non-NPSLE. No significant positive correlation was observed between CSF level and serum level of IL-6. CSF IL-6 was significant higher in the NPSLE group than the non-NPSLE (P < 0.001) group. Multivariable logistic analysis revealed that total score, ramified loops, and microangioma of eye sign were predictors for NPSLE after adjusting for SLE Disease Activity Index (SLEDAI) and antiphospholipid antibody (APL). Total score, ramified loops, microangioma of eye sign, and SLEDAI remain significant predictors for NPSLE after adjusting for CSF IL-6. Using receiver operating characteristics curve analysis, the cut-off point of potential predictors was applied in multivariable logistic analysis; APL, total score, ramified loops, and microangioma of eye sign remain significant predictors for NPSLE after adjusting for CSF IL-6.

CONCLUSION

Specific microvascular alterations of eye sign are predictors for the development of NPSLE in addition to increased IL-6 in the CSF.

Systemic Lupus Erythematosus Presenting as Walking Corpse Syndrome

Cotard syndrome, also known as "Walking Corpse Syndrome", is a clinical entity characterized by fixed delusions that one is dead or dying. This is a neuropsychiatric manifestation of brain pathology affecting the non-dominant frontotemporal and parietal lobes, particularly the fusiform gyrus. Prior literature has indicated that the etiology of Cotard syndrome may include structural changes related to brain injury, tumors, and temporal lobe epilepsy. We now present a case in which Cotard syndrome is related to systemic lupus erythematosus (SLE). Neuropsychiatric symptoms are atypical manifestations of SLE. Delusions, hallucinations, and other psychotic symptoms can result as a consequence of the disease itself or from corticosteroid treatment. A diagnosis of SLE-induced psychosis can be elusive; however, conducting a thorough workup is crucial as untreated psychosis secondary to lupus cerebritis can worsen without intervention. We present a clinical unique case of SLE cerebritis, diagnostic challenge, and management.

Mouse models, antibodies, and neuroimaging: Current knowledge and future perspectives in neuropsychiatric systemic lupus erythematosus (NPSLE)

As a chronic autoimmune disease systemic lupus erythematosus (SLE) can also affect the central and the peripheral nervous system causing symptoms which are summed up as neuropsychiatric systemic lupus erythematosus (NPSLE). These symptoms are heterogenous including cognitive impairment, seizures, and fatigue, leading to morbidity or even mortality. At present, little is known about the pathophysiological processes involved in NPSLE. This review focuses on the current knowledge of the pathogenesis of NPSLE gained from the investigation of animal models, autoantibodies, and neuroimaging techniques. The antibodies investigated the most are anti-ribosomal P protein antibodies (Anti-rib P) and anti-N-Methyl-D-Aspartic Acid Receptor 2 antibodies (Anti-NR2), which represent a subpopulation of anti-dsDNA autoantibodies. Experimental data demonstrates that Anti-rib P and Anti-NR2 cause different neurological pathologies when applied intravenously (i.v.), intrathecally or intracerebrally in mice. Moreover, the investigation of lupus-prone mice, such as the MRL/MpJ-Faslpr/lpr strain (MRL/lpr) and the New Zealand black/New Zealand white mice (NZB × NZW F1) showed that circulating systemic antibodies cause different neuropsychiatric symptoms compared to intrathecally produced antibodies. Furthermore, neuroimaging techniques including magnetic resonance imaging (MRI) and positron emission tomography (PET) are commonly used tools to investigate structural and functional abnormalities in NPSLE patients. Current research suggests that the pathogenesis of NPSLE is heterogenous, complex and not yet fully understood. However, it demonstrates that further investigation is needed to develop individual therapy in NPSLE.

Clinical associations of cognitive dysfunction in systemic lupus erythematosus

OBJECTIVE

Cognitive dysfunction in SLE is common, but clinical risk factors are poorly understood. This study aims to explore the associations of cognitive dysfunction in SLE with disease activity, organ damage, biomarkers and medications.

METHODS

We performed cross-sectional cognitive assessment using a conventional neuropsychological test battery, with normative values derived from demographically matched healthy subjects. Endpoints included two binary definitions of cognitive dysfunction and seven individual cognitive domain scores. Clinical parameters included disease activity (SLEDAI-2K) and organ damage (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index). We performed regression analyses to determine associations between clinical parameters and cognitive endpoints.

RESULTS

89 patients with SLE were studied, with median age of 45 and disease duration of 15 years. Organ damage was significantly associated with severe cognitive dysfunction (OR 1.49, CI 1.01-2.22) and worse cognitive test performance in three of the seven individual cognitive domains. In contrast, no significant associations were found between SLEDAI-2K at the time of cognitive assessment and any cognitive endpoints on multivariate analysis. Higher time-adjusted mean SLEDAI-2K was associated with better verbal memory scores but had no significant associations with other cognitive endpoints. The presence of anti-dsDNA antibodies and high IFN gene signature were negatively associated with severe cognitive dysfunction; there were no significant associations with the other autoantibodies studied or any medications. Substance use was significantly associated with lower psychomotor speed. Only 8% of patients who had cognitive dysfunction on testing had been recognised by clinicians on their SDI score.

CONCLUSIONS

In SLE, cognitive dysfunction was positively associated with organ damage, but not associated with disease activity, and serological activity and high IFN signature were negatively associated. Cognitive dysfunction was poorly captured by clinicians. These findings have implications for preventative strategies addressing cognitive dysfunction in SLE.

The conundrum of neuropsychiatric systemic lupus erythematosus: Current and novel approaches to diagnosis

Recognising neuropsychiatric involvement by systemic lupus erythematosus (SLE) is of growing importance, however many barriers to this exist at multiple levels of our currently available diagnostic algorithms that may ultimately delay its diagnosis and subsequent treatment. The heterogeneous and non-specific clinical syndromes, serological and cerebrospinal fluid (CSF) markers and neuroimaging findings that often do not mirror disease activity, highlight important research gaps in the diagnosis of neuropsychiatric SLE (NPSLE). Formal neuropsychological assessments or the more accessible screening metrics may also help improve objective recognition of cognitive or mood disorders. Novel serum and CSF markers, including autoantibodies, cytokines and chemokines have also shown increasing utility as part of diagnosis and monitoring, as well as in distinguishing NPSLE from SLE patients without SLE-related neuropsychiatric manifestations. Novel neuroimaging studies also expand upon our existing strategy by quantifying parameters that indicate microarchitectural integrity or provide an assessment of neuronal function. Some of these novel markers have shown associations with specific neuropsychiatric syndromes, suggesting that future research move away from considering NPSLE as a single entity but rather into its individually recognized neuropsychiatric manifestations. Nevertheless, it is likely that a composite panel of these investigations will be needed to better address the gaps impeding recognition of neuropsychiatric involvement by SLE.

Fibromyalgia, mood disorders, cognitive test results, cognitive symptoms and quality of life in systemic lupus erythematosus

OBJECTIVES

Cognitive dysfunction, and comorbidities such as mood disorder and fibromyalgia, are common in SLE. This study aims to explore the associations between fibromyalgia, mood disorders, cognitive symptoms and cognitive dysfunction in SLE patients, and their impact on quality of life.

METHODS

We tested cognition in SLE patients and healthy controls, and evaluated cognitive symptoms, mood disorder, fibromyalgia, fatigue and quality of life using patient-reported outcome measures. We examined associations of these comorbidities with both patient-reported cognitive symptoms and cognitive test performance.

RESULTS

High fibromyalgia symptom score and history of depression or anxiety were associated with cognitive dysfunction. There were no significant associations between current depression, anxiety symptoms or fatigue score and objective cognitive dysfunction. In contrast, mood disorder symptoms, history of mood disorder, fibromyalgia symptoms and fatigue all had significant associations with patient-reported cognitive symptoms. There were no significant associations between patient-reported cognitive symptoms and objective cognitive dysfunction. Objective cognitive dysfunction, patient-reported cognitive symptoms, history of mood disorder and fibromyalgia symptoms all had significant associations with poorer quality of life; fibromyalgia had the biggest impact.

CONCLUSIONS

Cognitive symptoms are common in SLE, but there were no associations between cognitive symptoms and objective cognitive dysfunction. Depression, anxiety and fibromyalgia were more consistently associated with patient-reported cognitive symptoms than with objective cognitive dysfunction. These factors all have a significant impact on quality of life. Understanding the discrepancy between patient-reported cognitive symptoms and cognitive test performance is essential to advance care in this area of unmet need.

Causal association between systemic lupus erythematosus and the risk of dementia: A Mendelian randomization study

Introduction

It is well-documented that systemic lupus erythematosus (SLE) is associated with dementia. However, the genetic causality of this association remains unclear. Mendelian randomization (MR) was used to investigate the potential causal relationship between SLE and dementia risk in the current study.

Methods

We selected 45 single nucleotide polymorphisms (SNPs) associated with SLE from publicly available genome-wide association studies (GWAS). Summary level statistics were obtained from the dementia GWAS database. MR estimates were performed using the inverse variance weighted (IVW) method, MR-Egger method and weighted median (WM) method. Cochran's Q test, the intercept of MR-Egger, MR-Pleiotropy Residual Sum and Outlier method, leave-one-out analysis and funnel plot were applied for sensitivity analyses.

Results

No significant causal association was found between SLE and any type of dementia, including Alzheimer's disease, vascular dementia, frontotemporal dementia, and dementia with Lewy bodies. These findings were robust across several sensitivity analyses.

Conclusion

Overall, our findings do not support a causal association between SLE and dementia risk.

Neurophysiological evaluation of juvenile systemic lupus erythematosus

Background

Peripheral nervous system and the central nervous system involvement in systemic lupus erythematosus (SLE) patients are one of the major causes of morbidity and mortality. The aim of this work was to study the nervous system clinically and electrophysiologically in children with systemic lupus erythematosus.

Results

The study was carried out on thirty-eight children with SLE. Their age ranged from 5 to 16 years. The most encountered neurologic manifestations were tremors. It was observed in 47.4% of children, followed by headache in 39.5%, sensory manifestation as numbness in 23.7%, cerebrovascular stroke in 5.3%, and chorea in 2.6%, which was unilateral mostly in the upper limb, tics, and convulsion had the same percentage. Around 16% of children had positive findings in MRI, such as cerebrovascular disease, minimal hematoma, pseudotumorcerebri, vasculitis, and ectatic ventricles. Subclinical peripheral neuropathy was reported in nearly 52.6% of children, and clinical peripheral neuropathy was reported in 23.6%. Pure sensory subclinical peripheral neuropathy was detected in 13.1% of children, but mixed subclinical peripheral neuropathy was detected in 39.4%. Nearly 53% of studied children had an abnormal somatosensory-evoked potential study of posterior tibial and median nerves.

Conclusion

The current study reported that the clinical neurological manifestations in juvenile SLE is common. Peripheral neuropathy is commonly detected, which could be either clinical or sub-clinical. Somatosensory evoked potential study is of value for early detection of central affection.

So, we recommend more studies to determine the guidelines when to order these informative investigations for children with JSLE.

Montreal cognitive assessment as a screening instrument for cognitive impairment in systemic lupus erythematosus patients without overt neuropsychiatric manifestations

OBJECTIVES

The Montreal Cognitive Assessment (MoCA) is an increasingly used screening tool for cognitive impairment. The aim of this study was to examine how MoCA performed in identifying cognitive impairment (CI) domains in SLE patients compared with formal standardized neuropsychological testing (NPT). Factors related to SLE disease, immunologic and psychological state associated with CI were also explored.

METHODS

This cross-sectional study recruited 50 SLE patients without overt neuropsychiatric manifestations from April 2017 to May 2018. The patients were evaluated with MoCA, formal NPT and the Depression, Anxiety, and Stress Scales (DASS) 42-item self-report questionnaire. Values of sensitivity and specificity were computed for different cut-offs of MoCA within each cognitive domain of NPT and descriptive analysis was used to identify the factors affecting cognitive function.

RESULTS

The median score for MoCA was 27.5 (range 22-30). Using a MoCA cutoff of <26, 18 (36%) were identified to have CI using NPT compared to 8 (16%) using MoCA. The most frequently affected cognitive domain was executive functioning with 15 affected patients. Sensitivities and specificities of the MoCA range from 50% to 100% and 5.7% to 16.7%, respectively, across cognitive domains. A lower MoCA cutoff of <25 improve sensitivity of identifying impairment in executive functioning from 60% to 80%. In univariate analysis, DASS scores, disease activity, presence of antiphospholipid antibodies, presence of concurrent autoimmune disease, current, and cumulative corticosteroid therapy did not predict cognitive performance.

CONCLUSION

MoCA may be a useful screening tool to identify the most frequently affected cognitive domain which is executive functioning using a lower cutoff of <25 in SLE patients without overt neuropsychiatric manifestations.

Neuropsychiatric manifestations in childhood-onset systemic lupus erythematosus

Neuropsychiatric manifestations occur frequently and are challenging to diagnose in childhood-onset systemic lupus erythematosus (SLE). Most patients with childhood-onset SLE have neuropsychiatric events in the first 2 years of disease. 30-70% of patients present with more than one neuropsychiatric event during their disease course, with an average of 2-3 events per person. These symptoms are associated with disability and mortality. Serum, cerebrospinal fluid, and neuroimaging findings have been described in childhood-onset SLE; however, only a few have been validated as biomarkers for diagnosis, monitoring response to treatment, or prognosis. The aim of this Review is to describe the genetic risk, clinical and neuroimaging characteristics, and current treatment strategies of neuropsychiatric manifestations in childhood-onset SLE.

Potential diagnostic biomarkers for schizophrenia

Schizophrenia (SCH) is a complex and severe mental disorder with high prevalence, disability, mortality and carries a heavy disease burden, the lifetime prevalence of SCH is around 0.7%-1.0%, which has a profound impact on the individual and society. In the clinical practice of SCH, key problems such as subjective diagnosis, experiential treatment, and poor overall prognosis are still challenging. In recent years, some exciting discoveries have been made in the research on objective biomarkers of SCH, mainly focusing on genetic susceptibility genes, metabolic indicators, immune indices, brain imaging, electrophysiological characteristics. This review aims to summarize the biomarkers that may be used for the prediction and diagnosis of SCH.

Cognitive performance in systemic lupus erythematosus patients: a cross-sectional and longitudinal study

Background

Previous research has provided evidence for cognitive dysfunction as a common symptom of systemic lupus erythematosus (SLE). In light of this, the primary goal of this study was to investigate how cognitive impairment in this patient group develops over time. In addition, the present dataset contributes to delineating the specific abilities that are impaired in SLE patients as well as answering the question whether the disease affects the cognition of SLE patients with neuropsychiatric manifestations (NPSLE) and without (non-NPSLE) in distinct ways.

Methods

91 female participants (33 NPSLE, 29 non-NPSLE, 29 healthy controls (HC)) underwent standardized neurocognitive testing. A total of ten different cognitive abilities were assessed, among others executive function, memory, and attention. Some of the participants (30 NPSLE patients, 22 non-NPSLE, 13 HC) were tested twice (mean time between testing sessions: 50 months) to enable longitudinal tracking of cognitive abilities. Analyses of Variance (ANOVA) were conducted to determine whether cognitive performance differed cross-sectionally between the groups. Linear mixed effects models were fit to investigate performance differences between the groups over time.

Results

Cross-sectional analysis at follow-up demonstrated that the cognitive performance of both NPSLE and non-NPSLE was significantly lower than that of HC for the motor speed and the psychomotor speed domain. Additionally, NPSLE patients performed significantly weaker than HC in the complex attention domain. At the same time, the cross-sectional data did not yield any support for performance differences between NPSLE and non-NPSLE patients. Weak positive correlations between disease duration and psychomotor speed, motor speed and reaction time emerged. A temporal progression of cognitive dysfunction in SLE patients was not confirmed.

Conclusions

Cognitive performance is affected in both non-NPSLE and NPSLE patients. However, a linear decline in performance over time could not be verified. More in-depth longitudinal assessments of cognition in SLE patients are needed to establish how cognitive abilities in this patient population develop over time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41927-022-00253-3.

The expanding role of synthetic nucleic acids for diagnosis and treatment

PURPOSE OF REVIEW

The presence of autoantibodies is a characteristic and diagnostic index of systemic lupus erythematosus (SLE). Antidouble-stranded DNA (antids-DNA) antibodies are the most frequent autoantibodies found in SLE related to the diagnosis and disease activity of SLE, and are measured by established methods like ELISA as a polyclonal autoantibody. However, there is no reliable data on the relationship between the respective reactivity of these polyclonal antids-DNA antibodies against different epitopes generated from the original antigen and the disease phenotype. Of the complications in SLE, neuropsychiatric SLE (NPSLE) is a troublesome and frequent phenotype of the disease but no specific diagnostic autoantibodies in serum have been found. First in this review, the possibility of antids-DNA antibodies for identifying primary NPSLE in patients with SLE based on the reactivity of different synthetic nucleic acids is described as a diagnostic marker. The purpose of this review is to examine diagnostic and therapeutic opportunities to modulate autoimmune in the central nervous system (CNS) developing the CNS inflammatory disorders.

RECENT FINDINGS

Khatri et al. investigated antids-DNA antibodies in order to develop a reliable method based on the application of synthetic nucleic acids and protein-based antigen arrays to characterize autoreactive antibodies specially for NPSLE. They found autoantibodies in three particular synthetic double stranded antigens and the antinuclear antibody patterns in ordinary lupus and NPSLE. These discoveries are leading to precision medicine in the CNS inflammatory disorders.

SUMMARY

Verifying the similarity of antids-DNA obtained from patients with NPSLE can be useful as a diagnostic marker. mRNA vaccination can locally suppress autoimmunity in the CNS associated with critical steps for the develop of CNS autoinflammation. Synthetic nuclei acids may provide a diagnostic and therapeutic target in patients with autoimmune CNS inflammatory disorders.

Heterogeneity of Stroke in Patients with Systemic Lupus Erythematosus

Objective The underlying pathophysiology varies according to stroke subtype. However, stroke heterogeneity among patients with systemic lupus erythematosus (SLE) remains unstudied. We hypothesized that the contribution of SLE to stroke might vary according to its subtype and investigated the associations of SLE and various stroke subtypes. Methods Diagnostic codes and electronic medical records were used to identify 70 patients with SLE who developed acute cerebral infarction or intracerebral hemorrhaging at four tertiary referral hospitals between 2008 and 2018. Intracerebral hemorrhaging was classified as lobar or deep, while cerebral infarction was classified according to the SSS-TOAST criteria. Physician notes were used to identify SLE activity, and their prevalences were compared among stroke subtypes. Outcomes were collected from the patients' medical records. Results The most common stroke subtype in patients with SLE was that of undetermined causes (31%), followed by small artery occlusion (16%), cardioaortic embolism (13%), other causes (11%), lobar hemorrhaging (10%), deep hemorrhaging (10%), and large artery atherosclerosis (9%). Stroke onset occurred during a period of high SLE activity in 21 patients (30%). The proportion of patients with high SLE activity varied according to stroke subtype (p=0.039) and was highest for cerebral infarction with undetermined causes. Stroke recurrence or death was observed in 40% of patients within 5 years after the initial stroke onset. Conclusion The contributions of SLE to stroke varied significantly according to the stroke subtype. Given the unfavorable prognosis, close stroke subtype-specific observation by rheumatologists and stroke specialists is recommended after stroke events.

Evaluation of the Montreal Cognitive Assessment as a screening tool for cognitive dysfunction in SLE

Objectives

Cognitive dysfunction in SLE is common and associated with significant morbidity but is currently underdetected. Early detection requires the use of screening tests, as formal diagnostic cognitive testing is time-consuming. This study aims to evaluate the Montreal Cognitive Assessment (MoCA) as a screening tool for cognitive dysfunction in SLE.

Methods

Patients with SLE (n=95) and demographically matched healthy control participants (n=48) underwent cognitive testing using the 1-hour neuropsychiatric test battery recommended by the American College of Rheumatology for use in SLE and the MoCA. We used regression analyses to determine associations between MoCA and cognitive test scores. We assessed several MoCA cut-offs for predicting cognitive impairment in terms of sensitivity, specificity, positive predictive value and negative predictive value. Receiver operating curve analyses were used to determine the diagnostic accuracy of the MoCA cut-off thresholds.

Results

We found a significant correlation between MoCA score and 9 of the 10 cognitive endpoints studied (all p<0.001). Receiver operating curve analysis suggested that a MoCA cut-off of <27 had highest diagnostic accuracy across the cognitive impairment definitions (area under the curve 0.76–0.78). Using a screening cut-off of <28, the MoCA had sensitivity of 83%–94% and specificity of 46%–59%, depending on the impairment definition used.

Conclusions

The MoCA correlates strongly with cognitive test results in SLE and has sufficient sensitivity for use as a screening tool with a cut-off of <28 as the optimal threshold. This tool can be incorporated into clinical practice for screening for cognitive dysfunction in SLE.

PET-CT in brain disorders: The South African context

Positron emission tomography combined with X-ray computed tomography (PET-CT) has an established role in the management of brain disorders, but may be underutilised in South Africa. Possible barriers to access include the limited number of PET-CT facilities and the lack of contemporary guidelines for the use of brain PET-CT in South Africa. The current review aims to highlight the evidence-based usage of brain Positron emission tomography (PET) in dementia, movement disorders, brain tumours, epilepsy, neuropsychiatric lupus, immune-mediated encephalitides, and brain infections. While being areas of research, there is currently no clinical role for the use of PET-CT in traumatic brain injury or in psychiatric or neurodevelopmental disorders. Strategies to expand the appropriate use of PET-CT in brain disorders are discussed in this article.

Neuropsychiatric involvement in juvenile-onset systemic lupus erythematosus: Data from the UK Juvenile-onset systemic lupus erythematosus cohort study

INTRODUCTION

Juvenile-onset systemic lupus erythematosus (JSLE) is a rare autoimmune/inflammatory disease with significant morbidity and mortality. Neuropsychiatric (NP) involvement is a severe complication, encompassing a heterogeneous range of neurological and psychiatric manifestations.

METHODS

Demographic, clinical, and laboratory features of NP-SLE were assessed in participants of the UK JSLE Cohort Study, and compared to patients in the same cohort without NP manifestations.

RESULTS

A total of 428 JSLE patients were included in this study, 25% of which exhibited NP features, half of them at first visit. Most common neurological symptoms among NP-JSLE patients included headaches (78.5%), mood disorders (48.6%), cognitive impairment (42%), anxiety (23.3%), seizures (19.6%), movement disorders (17.7%), and cerebrovascular disease (14.9%). Peripheral nervous system involvement was recorded in 7% of NP-SLE patients. NP-JSLE patients more frequently exhibited thrombocytopenia (<100 × 109/L) (p = 0.04), higher C-reactive protein levels (p = 0.01), higher global pBILAG score at first visit (p < 0.001), and higher SLICC damage index score at first (p = 0.02) and last (p < 0.001) visit when compared to JSLE patients without NP involvement.

CONCLUSIONS

A significant proportion of JSLE patients experience NP involvement (25%). Juvenile-onset NP-SLE most commonly affects the CNS and is associated with increased overall disease activity and damage.

Progressive muscle weakness and amyotrophy during pregnancy as the first manifestation of systemic lupus erythematosus: A case report and review of literature

BACKGROUND

Systemic lupus erythematosus is a common autoimmune disease involving multiple systems. Clinical involvement of the central and peripheral nervous systems is not unusual, but peripheral neuropathy in systemic lupus erythematosus with chronic inflammatory demyelinating polyneuropathy is uncommon. Our study aimed to illustrate the clinical features, diagnosis, and treatment of systemic lupus erythematosus combined with chronic inflammatory demyelinating polyneuropathy, and to aid in the identification of peripheral neuropathy in systemic lupus erythematosus.

METHODS

This article reports a case of systemic lupus erythematosus with onset in pregnancy, with chronic inflammatory demyelinating polyneuropathy as the first manifestation. We then analyze the identification of common peripheral neuropathy in systemic lupus erythematosus in detail, based on a literature review of confirmed cases of systemic lupus erythematosus combined with chronic inflammatory demyelinating polyneuropathy.

RESULTS

A 34-year-old woman presented progressive muscle weakness and muscular atrophy in the extremities during pregnancy, 3 years previously. At 4 months after onset, she had completely lost the ability to hold objects and walk, and had slight numbness in the limbs, without paresthesia. Her condition was misdiagnosed as "motor neuron disease" at the time. Three years after onset, her condition was revisited because of nephrotic syndrome, and she was diagnosed with nephrotic syndrome and peripheral nerve injury caused by systemic lupus erythematosus. After immunosuppressive treatment with corticosteroids and intravenous cyclophosphamide, her symptoms of muscle weakness were markedly improved. This article summarizes the characteristics of systemic lupus erythematosus combined with chronic inflammatory demyelinating polyneuropathy that have been reported in the literature, from the aspects of morbidity, disease progression, nerve injury, laboratory examinations, and treatment response.

CONCLUSIONS

Our identification of a common peripheral neuropathy in systemic lupus erythematosus will help to improve clinicians' understanding of various peripheral neuropathies in systemic lupus erythematosus. It will also aid in the early diagnosis and treatment of such patients, thus improving their long-term prognosis.

Serum BDNF and cognitive dysfunction in SLE: findings from a cohort of 111 patients

OBJECTIVE

The association between brain-derived neurotrophic factor (BDNF) and neuropsychiatric systemic lupus erythematosus (NPSLE) is controversial in the literature. Cognitive dysfunction (CD) is a common, underdiagnosed NPSLE manifestation, but its pathophysiology is unknown. Thus, we investigate serum BDNF as a potential biomarker of CD in a cohort of SLE patients.

METHODS

We included 63 SLE patients, 48 NPSLE, and 57 age- and gender-matched controls (CON). All participants underwent neuropsychological assessment. Data on cardiovascular comorbidities, SLE disease activity index (SLEDAI), and Systemic Lupus International Collaborating Clinics damage index (SLICC-DI) were compiled. Multiple regression analyses evaluated predictors of serum BDNF levels.

RESULTS

Serum BDNF levels were lower in SLE and NPSLE patients than in CON (SLE 800.4 ± 502.7 vs. NPSLE 779.7 ± 426.3 vs. CON 1,345.5 ng/mL ± 438.4; p < 0.001). In addition, hypertension (B: - 192.5, SE: 84.3, 95% CI: - 359.7 to - 25.3, p = 0.024) and SLICC-DI score (B: - 75.9, SE: 27.2, 95% CI: - 129.8 to - 22, p = 0.006) were predictors of serum BDNF levels in SLE. There was no relation between BDNF levels and CD.

CONCLUSION

BDNF levels are lower in SLE patients than CON and inversely associated with hypertension and SLICC-DI scores. No association between BDNF levels and CD or NPSLE was observed in this cohort. These findings indicate that BDNF may be associated with overall burden in SLE rather than specific manifestations such as cognition impairment. Key Points • BDNF is associated with an overall burden in SLE rather than specific manifestations such as cognition dysfunction. • BDNF levels are reduced in patients with SLE, and higher SLICC-DI scores and hypertension are independent predictors of lower serum BDNF levels. • The cognitive dysfunction rate is elevated (46%) among Brazilian SLE patients.

Short- and Long-Term Outcome of Systemic Lupus Erythematosus Peripheral Neuropathy: Bimodal Pattern of Onset and Treatment Response

BACKGROUND/OBJECTIVE

Our aim was to describe the short- and long-term outcome of peripheral neuropathy (PN) attributed exclusively to systemic lupus erythematosus (SLE).

METHODS

Systemic lupus erythematosus patients with defined PN (clinical and electroneuromyography) were retrospectively evaluated at onset, 1-year, and 5-year follow-up using a standardized electronic chart database that started in 2000. Exclusion criteria were comorbidities, drugs, and infections. Age-, sex-, and disease duration-matched SLE patients without PN were selected as controls.

RESULTS

Lupus PN was identified in 38 (1.8%) of 2074 patients, and almost two thirds had PN onset in the first 5 years of SLE (63.2%). Peripheral neuropathy SLE had higher frequencies of cutaneous vasculitis (50% vs 21.1%, p = 0.002), lymphopenia (60.5% vs 36.8%, p = 0.027), anti-Sm (52.6% vs 27.6%, p = 0.013), and higher SLEDAI-2K scores (11.5 ± 10.5 vs 4.9 ± 6.7, p < 0.001) compared with controls. The most common type was polyneuropathy (71.1%) with sensory-motor pattern (68.4%). At PN diagnosis, all patients received glucocorticoid and 97.4% started immunosuppressive therapy (50% intravenous cyclophosphamide, 42.1% azathioprine). After 1-year follow-up, 92.1% had a favorable outcome with complete (36.8%) or partial remission (55.2%), in parallel with a decrease in prednisone dose (48.3 ± 17.9 vs 15.3 ± 13.4 mg/d, p < 0.001), symptomatic therapy (57.9% vs 29.7%, p = 0.02), and SLEDAI-2K score (11.5 ± 10.5 vs 1.7 ± 3.7, p < 0.001). SLEDAI-2K scores were higher in patients who had PN onset with less than 1 year of SLE duration, compared with those with more than 5 years of disease (21.3 ± 9.1 vs 3.9 ± 5.3, p < 0.001). Early-PN-onset group had a better response to treatment (complete remission at 1-year follow-up 61.5% vs 25%, p = 0.039). At 5-year follow-up, 89.3% remained with complete/partial remission.

CONCLUSIONS

Peripheral neuropathy attributed to SLE itself is a rare manifestation with a bimodal pattern, characterized by a predominant early-onset group associated with high disease activity and a higher rate of complete remission, and a late-onset group with low disease activity and a partial therapy response.

Quercetin and/or Ascorbic Acid Modulatory Effect on Phenobarbital-Induced Sleeping Mice Possibly through GABAA and GABAB Receptor Interaction Pathway

Depressive disorder is a recurrent illness that affects large numbers of the general population worldwide. In recent years, the goal of depression treatment has moved from symptomatic response to that of full remission. However, treatment-resistant depression is a major challenge in the treatment of depression or depression-related disorders. Consensus opinion, therefore, suggests that effective combined aggressive initial treatment is the most appropriate strategy. This study aimed to evaluate the effects of quercetin (QUR) and/or ascorbic acid (AA) on Phenobarbital-induced sleeping mice. QUR (50 mg/kg) and/or AA (25 mg/kg) with or without intraperitoneally pre-treated with GABA receptor agonist (diazepam: 2 mg/kg, i.p.) or antagonist (Flumazenil: 2.5 mg/kg, i.p.) to underscore the effects, as well as the possible involvement of the GABA receptor in the modulatory action of QUR and AA in sleeping mice. Additionally, an in silico study was undertaken to predict the involvement of GABA receptors in the sleep mechanism. Findings suggest that the pretreatment of QUR and AA modulated the onset and duration of action of the standard drugs in experimental animals. The acute administration of QUR and/or AA significantly (p < 0.05) reversed the DZP-mediated onset of action and slightly reversed the duration of sleep time in comparison to the vehicle (control) group. A further combination of QUR or AA with the FLU resulted in an enhancement of the onset of action while reducing the duration of action, suggesting a FLU-like effect on the test animals. In in silico studies, AA and QUR showed good to moderate binding affinities with GABA_A and GABA_B receptors. Both QUR and AA produced a stimulatory-like effect on mice, possibly through the GABA_A and GABA_B receptor interaction pathways. Further studies are necessary to verify this activity and clarify the exact mechanism of action(s) involved.

Neuro-psychiatric manifestations in patients with systemic lupus erythematosus: A systematic review and results from the Swiss lupus cohort study

Objectives

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease associated with neuro-psychiatric (NP) manifestations. Frequency and patterns of neuro-psychiatric systemic lupus erythematosus (NPSLE) vary substantially between patients. We conducted a systematic review (SR) of the literature and examined prevalence and characteristics of NPSLE in the Swiss SLE cohort study (SSCS).

Methods

The SR search was performed between January 1999 and January 2020. We included prospective/cross-sectional studies focusing on NPSLE. We secured study characteristics, cohort compositions and frequencies of NP manifestations, assessed heterogeneity across reports and investigated sources of variation using meta-regression models. Regarding the SSCS, we reviewed all patients included and classified NP manifestations.

Results

The SR searches identified 530 studies. We included 22 studies in our meta-analysis, the mean frequency of NPSLE ranged from 10.6% to 96.4%. The frequency of NPSLE in the SSCS was 28.1%. Severe events including cerebrovascular insults, seizures and psychosis appeared in 7.1%, 5.3% and 6.5% respectively. There was a linear relationship between duration of SLE and cumulative incidence of NPSLE.

Conclusions

The spectrum of NPSLE is very broad. The diagnostic work-up and rates of reported manifestations varied substantially across studies. We call for concerted efforts and consensus regarding definitions of NPSLE that will facilitate accurate diagnosis and attribution to SLE, particularly with a view to timely intervention and patient outcomes.

Pattern and prevalence of neuropsychiatric lupus: a retrospective study from a tertiary level hospital in Bangladesh

Background

Neuropsychiatric systemic lupus erythematosus (NPSLE) is well known for its varying presentations and poor outcomes, but little is evident about its distribution and characteristics among the Bangladeshi population. This study aimed to assess the pattern and prevalence of neuropsychiatric symptoms in female systemic lupus erythematosus (SLE) patients of Bangladesh. A retrospective study was conducted at a tertiary care hospital in Dhaka, Bangladesh, between January and December 2018. One hundred female SLE patients were included in the study purposively. Data were collected on sociodemographic and clinical characteristics of diagnosed SLE cases visiting the SLE clinic and indoor medicine department. Neuropsychiatric (NP) syndromes were defined according to the widely accepted American College of Rheumatology (ACR) nomenclature and case definitions.

Results

A total of 244 NP events were identified in fifty-five patients. Headache was the most frequent symptom (55%), followed by cognitive dysfunction (50%), anxiety (49%), psychosis (43%), seizure (23%), depression (17%), and cerebrovascular disease (ischemic type, 7%). The NP manifestations were more prevalent among urban residents (58.2%), younger patients (41.8%), and patients with graduate-level education (34.5%). Besides, young age at diagnosis (p = 0.038), Raynaud’s phenomenon (p = 0.015), other organ involvement (p < 0.001), and time of NPSLE development (p < 0.001) were found to be significantly associated with the development of these manifestations.

Conclusion

NP damage is prevalent among Bangladeshi female SLE patients (55%) with headache and cognitive dysfunction being the most common symptoms. Routine screening for neuropsychiatric symptoms among suspected SLE cases and further evaluation with a larger population are warranted.

Metrics and definitions used in the assessment of cognitive impairment in systemic lupus erythematosus: A systematic review

OBJECTIVE

To review: 1) degree of conformity to the American College of Rheumatology neuropsychological battery (ACR-NB) among studies that used a NB, 2) review definitions of cognitive impairment (CI) from studies that used a NB, and 3) characterize measurement tools used to assess CI in systemic lupus erythematosus (SLE).

METHODS

The literature search was conducted in Ovid Medline, Embase, and PsycINFO for articles on CI in adult SLE patients. We reviewed studies that used a NB and compared their tests to the ACR-NB to assess the degree of conformity. Definitions of CI from studies that used a NB were reviewed when sufficient information was available. We reviewed and categorized CI measurement tools into four broad categories: NB, screening, incomplete/mixed batteries, and computerized batteries.

RESULTS

Of 8727 references, 118 were selected for detailed review and 97 were included in the final analysis. Of 43 studies that used a NB, none of the studies used the ACR-NB exactly as published. Many studies supplemented with other tests. Overall, there was inconsistent use of ACR-NB tests. Definitions for CI varied, with cut-offs ranging from 1 to 3 standard deviations below normative values on domains/tests varying in type and number. The most frequently used measurement tool for assessing CI in SLE was a NB. Use of screening tests and computerized batteries have also increased over the last decade.

CONCLUSION

The assessment and definition of CI in SLE remains heterogeneous. A consensus meeting to address existing inconsistencies should be considered to harmonize the field of CI in SLE.

Factors associated with neuropsychiatric involvement in Latin American patients with systemic lupus erythematosus

INTRODUCTION

Factors related to presentation of neuropsychiatric (NP) SLE manifestations, early in the course of the disease, and during follow up have not been clearly established.

PURPOSE

To identify disease and non-disease related factors associated with NP manifestations in early SLE.

METHODS

We included 1193 patients from the GLADEL inception cohort free of NP involvement at cohort entry. We evaluated the association of demographic, clinical and laboratory data with NP involvement during follow-up.

STATISTICAL METHODS

Independent factors associated with NP involvement were identified using a multivariable Cox regression model.

RESULTS

Factors independently associated with NP manifestations were: mestizo ethnicity (HR 1.701, 95% CI 1.282-2.258, p = 0.0002), myalgias/myositis (HR 1.832, 95% CI 1.335-2.515, p = 0.0002), pneumonitis (HR 2.476, 95% CI 1.085-5.648, p = 0.0312), shrinking lung (HR 2.428, 95% CI 1.074-5.493, p = 0.0331) and hemolytic anemia (HR 1.629, 95% CI 1.130-2.347, p = 0.0089). Longer disease duration at cohort entry (13 to 24 months) was associated with a lower risk of developing NP manifestations (HR 0.642, 95% CI 0.441-0.934, p = 0.0206).

CONCLUSIONS

Patients with myalgias/myositis, pneumonitis, shrinking lung and hemolytic anemia are at higher risk of NP involvement, whereas longer disease duration at cohort entry is associated with a lower risk of developing NP involvement.

Cognitive Dysfunction in Systemic Lupus Erythematosus: Immunopathology, Clinical Manifestations, Neuroimaging and Management

Cognitive dysfunction (CD) is a common yet often clinically subtle manifestation that considerably impacts the health-related quality of life in patients with systemic lupus erythaematosus (SLE). Given the inconsistencies in CD assessment and challenges in its attribution to SLE, the reported prevalence of CD differs widely, ranging from 3 to 88%. The clinical presentation of CD in SLE is non-specific and may manifest concurrently with overt neuropsychiatric illness such as psychosis or mood disorders or as isolated impairment of attention, working memory, executive dysfunction or processing speed. Despite the lack of standardized and sensitive neuropsychological tests and validated diagnostic biomarkers of CD in SLE, significant progress has been made in identifying pathogenic neural pathways and neuroimaging. Furthermore, several autoantibodies, cytokines, pro-inflammatory mediators and metabolic factors have been implicated in the pathogenesis of CD in SLE. Abrogation of the integrity of the blood-brain barrier (BBB) and ensuing autoantibody-mediated neurotoxicity, complement and microglial activation remains the widely accepted mechanism of SLE-related CD. Although several functional neuroimaging modalities have consistently demonstrated abnormalities that correlate with CD in SLE patients, a consensus remains to be reached as to their clinical utility in diagnosing CD. Given the multifactorial aetiology of CD, a multi-domain interventional approach that addresses the risk factors and disease mechanisms of CD in a concurrent fashion is the favourable therapeutic direction. While cognitive rehabilitation and exercise training remain important, specific pharmacological agents that target microglial activation and maintain the BBB integrity are potential candidates for the treatment of SLE-related CD.

Cognitive dysfunction and associated neuroimaging biomarkers in antiphospholipid syndrome: a systematic review

Objectives

Cognitive dysfunction is common in patients with aPL (including primary APS or APS associated with SLE). Neuroimaging biomarkers may contribute to our understanding of mechanisms of cognitive dysfunction in these cohorts. This review aimed to investigate: (i) the prevalence of cognitive dysfunction in studies including neuroimaging biomarkers; and (ii) associations between cognition and neuroimaging biomarkers in patients with APS/aPL.

Methods

We conducted a systematic search of electronic databases PubMed, Science Direct, Scopus and PsycINFO, and included studies with descriptions of neuroimaging findings, cognitive dysfunction or both, in patients with aPL positivity (LA, IgG and IgM aCL and anti-β2 glycoprotein-I antibodies).

Results

Of 120 search results we included 20 eligible studies (6 APS, 4 SLE with APS/aPL and 10 NPSLE). We identified a medium risk of bias in 6/11 (54%) of cohort studies and 44% of case–control studies, as well as marked heterogeneity in cognitive assessment batteries, APS and aPL definitions, and neuroimaging modalities and protocols. The prevalence of cognitive dysfunction ranged between 11 and 60.5%. Structural MRI was the most common imaging modality, reporting cognitive dysfunction to be associated with white matter hyperintensities, ischaemic lesions and cortical atrophy (four with cerebral atrophy, two with white matter hyperintensities and two with cerebral infarcts).

Conclusion

Our findings confirm that cognitive impairment is commonly found in patients with aPL (including APS, SLE and NPSLE). The risk of bias, and heterogeneity in the cognitive and neuroimaging biomarkers reported does not allow for definitive conclusions.