Prevalence, involved domains, and predictor of cognitive dysfunction in systemic lupus erythematosus

[Formula: see text] Cognitive dysfunction in pediatric systemic lupus erythematosus: current knowledge and future directions

Cognitive dysfunction (CD) is a neurologic complication of pediatric systemic lupus erythematosus (SLE) that remains poorly understood and understudied, despite the potential negative effects of CD on long-term socioeconomic status and quality of life. Data regarding the prevalence and risk factors for CD in pediatric SLE as well as the optimal screening, treatment, and long-term outcomes for CD are lacking. In this review, we present current knowledge on CD in pediatric SLE with a focus on the application to clinical practice. We discuss the challenges in diagnosis, clinical screening methods, potential impacts, and interventions for this complication. Finally, we discuss the remaining gaps in our knowledge of CD in pediatric SLE, and avenues for future research efforts.

Cognitive dysfunction in systemic lupus erythematosus is associated with disease activity and oxidative stress: a comparative study with rheumatoid arthritis for identifying biomarkers

BACKGROUND

The prevalence and pathophysiological mechanisms of cognitive deficits (CD) Systemic Lupus Erythematosus (SLE) and Rheumatoid arthritis (RA) are very heterogeneous and poorly understood. We characterized CD in patients with SLE compared with RA patients and healthy controls. We compared the neuropsychological profile of SLE and RA with patients' oxidative/inflammatory biomarkers for CD.

METHODS

We performed a cross-sectional study, including 50 SLE patients, 29 RA patients, and 32 healthy controls. SLEDAI and DAS28 assessed disease activity. SF-36 questionnaire and a battery of cognitive tests were applied to all participants. Blood samples were collected to determine IL-6, S100ß, myeloperoxidase (MPO), malondialdehyde and reduced glutathione (GSH) alterations.

RESULTS

In the SLE group, higher GSH was associated with the absence of CD (With CD = 69 ± 49, Without CD = 112 ± 81, p = 0.030), while higher IL-6 was associated with the presence of CD in the RA group (With CD = 603 ± 173, Without CD = 431 ± 162, p = 0.032). Regarding specific cognitive domains, in SLE higher MPO was associated with poor performance in reasoning and abstraction (p = 0.039), higher IL-6 was associated with poor performance in inhibitory control and attention (p = 0.031), and higher GSH was associated with better performance in memory(p = 0.021). Higher SLEDAI was associated with poor performance in semantic fluency(p = 0.031), inhibitory control, and attention in the SLE group(p = 0.037). In the RA group, higher DAS-28 was associated with poor performance in executive functions(p = 0.016) and phonemic fluency (p = 0.003).

CONCLUSION

SLE patients' disease activity, inflammatory state, and oxidative stress were associated with CD. In RA patients, CD was associated with disease activity and inflammatory state. These results encourage further studies with larger samples aiming to confirm oxidative stress parameters as biomarkers of CD in SLE patients.

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.

Cognitive dysfunction in patients with childhood-onset systemic lupus erythematosus may impact treatment

BACKGROUND

Cognitive dysfunction (CD) is a widespread manifestation in adult systemic lupus erythematosus (SLE) patients, but this subject is rarely examined in patients with childhood-onset SLE (cSLE). This study aimed to assess the frequency of CD, its associations with lupus clinical manifestations and its impact on the health-related quality of life (HRQL) in young adult cSLE patients.

METHODS

We evaluated 39 cSLE patients older than 18 years. They underwent a rheumatologic evaluation and extensive neuropsychological assessment, encompassing all cognitive domains described by the American College of Rheumatology. HRQL was assessed with the WHOOQOL-BREEF, General Activities of Daily Living Scale (GADL) and Systemic Lupus Erythematosus-specific quality-of-life instrument (SLEQOL). The activity of SLE was evaluated with the modified sle disease activity index (sledai-2k).

RESULTS

Impairment in at least one cognitive domain was found in 35 (87.2%) patients. The most compromised domains were attention (64.1%), memory (46.2%), and executive functions (38.5%). Patients with cognitive impairment were older, had more accumulated damage and had worse socioeconomic status. Regarding the association between cognitive dysfunction and HRQL, memory impairment was correlated with worse environmental perception and a worse relationship with the treatment.

CONCLUSION

In this study, the frequency of CD in cSLE patients was as high as that in the adult SLE population. CD can significantly impact the response of cSLE patients to treatment, justifying preventive measures in the care of this population.

Assessing the Utility of the Montreal Cognitive Assessment in Screening for Cognitive Impairment in Patients With Systemic Lupus Erythematosus

OBJECTIVE

Screening for cognitive impairment (CI) in systemic lupus erythematosus (SLE) relies on the American College of Rheumatology (ACR) neuropsychological battery (NB). By studying the concurrent criterion validity, our goal was to assess the Montreal Cognitive Assessment (MoCA) as a screening tool for CI compared to the ACR-NB and to evaluate the added value of the MoCA to the Automated Neuropsychological Assessment Metrics (ANAM).

METHODS

A total of 285 adult SLE patients were administered the ACR-NB, MoCA, and ANAM. For the ACR-NB, patients were classified as having CI if there was a Z score of ≤-1.5 in ≥2 domains. The area under the curve (AUC) and sensitivities/specificities were determined. A discriminant function analysis was applied to assess the ability of the MoCA to differentiate between CI, undetermined CI, and non-CI patients.

RESULTS

CI was not accurately identified by the MoCA compared to the ACR-NB (AUC of 0.66). Sensitivity and specificity were poor at 50% and 69%, respectively, for the cutoff of 26, and 80% and 45%, respectively, for the cutoff of 28. The MoCA had a low ability to identify CI status. The addition of the MoCA to the ANAM led to improvement on the AUC by only 2.5%.

CONCLUSION

The MoCA does not have adequate concurrent criterion validity to accurately identify CI in patients with SLE. The low specificity of the MoCA may lead to overdiagnosis and concern among patients. Adding the MoCA to the ANAM does not substantially improve the accuracy of the ANAM. These results do not support using the MoCA as a screening tool for CI in patients with SLE.

Disability and cognitive impairment are interdependent in primary antiphospholipid syndrome

BACKGROUND

Cognitive impairment (CI) occurs at a high frequency in primary antiphospholipid syndrome (PAPS). Its psychosocial-related factors are of interest.

OBJECTIVE

We aimed to determine disability and perceived stress and their correlation with CI in PAPS.

METHODS

First study phase: a longitudinal study including patients with PAPS and paired controls for cardiovascular risk factors, age, and sex, determining CI with Montreal Cognitive Assessment (MoCA) and then repeating the measurement 1 year later. Second study phase: a cross-sectional analytical study by quantification of disability with the World Health Organization Disability Assessment Schedule (WHODAS 2.0) and perceived stress with the Perceived Stress Scale (PSS-14). Descriptive statistics and Spearman correlation coefficient were used.

RESULTS

Sixty-three patients with PAPS and 60 controls were studied. In PAPS, age (range, 48.0 ± 13.5 years), thrombotic artery events (TAE) (44.4%), and stroke/TIA (42.8%) were found. Disability was documented in the majority of WHODAS 2.0 domains and the total score for this was higher in participation and mobility, the stress level was normal, and 65.1% had CI. PAPS exhibited greater deterioration in the WHODAS 2.0 total score (p .017) and the MoCA test (p < .0001). Personal domains and the total WHODAS 2.0 score correlated inversely with MoCA. Life activities (rho = -0.419) and self-care (rho = -0.407) were those that correlated to the greatest degree. Stroke conferred risk for CI.

CONCLUSIONS

Disability in PAPS and CI are interdependent. New treatment options and neurocognitive stimulation strategies are necessary to maintain functionality and prevent further cognitive dysfunction in PAPS patients.

Neuropsychiatric Systemic Lupus Erythematosus: a remaining challenge

Systemic Lupus Erythematosus (SLE) is an autoimmune disease, which affects a wide range of organs with variable clinical features. Involvement of the nervous system is a challenging and multifaceted manifestation of the disease, presenting with a broad range of symptoms. Neuropsychiatric lupus (NPSLE) encompasses seven syndromes of the peripheral and 12 of the central nervous system, associated with a high disease burden. Despite advances in the management of SLE, NP manifestations still pose a challenge to clinicians. First, diagnosis and attribution to SLE is difficult due to the lack of specific biomarkers or imaging modalities. Second, therapeutic options are limited, and evidence is mainly based on case reports and expert consensus, as clinical trials are sparse. Moreover, no validated outcome measure on disease activity exists. Current recommendations for treatment include supportive as well as immunosuppressive medication, depending on the type and severity of manifestations. As NPSLE manifestations are increasingly recognized, a broader spectrum of therapeutic options can be expected.

Pyruvate kinase isoform M2 impairs cognition in systemic lupus erythematosus by promoting microglial synaptic pruning via the β-catenin signaling pathway

BACKGROUND

Neuropsychiatric systemic lupus erythematosus (NPSLE) is a severe complication, which involves pathological damage to the brain and cognitive function. However, its exact mechanism of action still remains unclear. In this study, we explored the role of microglia in the cognitive dysfunction of NPSLE mice. We also analyzed and compared the metabolites in the hippocampal tissues of the lupus model and control mice.

METHODS

MRL/MpJ-Fas^lpr (MRL/lpr) female mice were used as the NPSLE mouse model. Metabolomics was used to assess hippocampal glycolysis levels. Glucose, lactic acid, IL-6, and IL-1β of the hippocampus were detected by ELISA. Based on the glycolysis pathway, we found that pyruvate kinase isoform M2 (PKM2) in the hippocampus was significantly increased. Thus, the expression of PKM2 was detected by qRT-PCR and Western blotting, and the localization of PKM2 in microglia (IBA-1⁺) or neurons (NeuN⁺) was assessed by immunofluorescence staining. Flow cytometry was used to detect the number and phenotype of microglia; the changes in microglial phagocytosis and the β-catenin signaling pathway were detected in BV2 cells overexpressing PKM2. For in vivo experiments, MRL/lpr mice were treated with AAV9-shPKM2. After 2 months, Morris water maze and conditional fear tests were applied to investigate the cognitive ability of mice; H&E and immunofluorescence staining were used to evaluate brain damage; flow cytometry was used to detect the phenotype and function of microglia; neuronal synapse damage was monitored by qRT-PCR, Western blotting, and immunofluorescence staining.

RESULTS

Glycolysis was elevated in the hippocampus of MRL/lpr lupus mice, accompanied by increased glucose consumption and lactate production. Furthermore, the activation of PKM2 in hippocampal microglia was observed in lupus mice. Cell experiments showed that PKM2 facilitated microglial activation and over-activated microglial phagocytosis via the β-catenin signaling pathway. In vivo, AAV9-shPKM2-treated mice showed decreased microglial activation and reduced neuronal synapses loss by blocking the β-catenin signaling pathway. Furthermore, the cognitive impairment and brain damage of MRL/lpr mice were significantly relieved after microglial PKM2 inhibition.

CONCLUSION

These data indicate that microglial PKM2 have potential to become a novel therapeutic target for treating lupus encephalopathy.

Disrupted resting-state interhemispheric functional connectivity in systemic lupus erythematosus patients with and without neuropsychiatric lupus

PURPOSE

The aim of the study is to explore interhemispheric homotopic functional connectivity alterations in systemic lupus erythematosus (SLE) patients with and without neuropsychiatric lupus (NPSLE and non-NPSLE, respectively) and their potential correlations with clinical characteristics and neuropsychological performance.

METHODS

Based on resting-state functional MRI (rs-fMRI) data collected from SLE patients and matched healthy controls (HCs), the voxel-mirrored homotopic connectivity (VMHC) analysis was conducted to measure functional homotopy. Subsequently, correlations between altered functional homotopy and clinical/neuropsychological data were analyzed.

RESULTS

Compared with the HC group, both NPSLE and non-NPSLE groups showed attenuated homotopic connectivity in middle temporal gyrus (MTG), cuneus (CUN), middle occipital gyrus (MOG), angular gyrus (ANG), and postcentral gyrus (PoCG). NPSLE patients also exhibited decreased homotopic connectivity in inferior parietal gyrus (IPG) and middle frontal gyrus (MFG). Compared with non-NPSLE patients, NPSLE patients showed weaker interhemispheric homotopic functional connectivity in MOG. Decreased homotopic functional connectivity in PoCG, IPG, and MOG were associated with the anxiety state of SLE patients.

CONCLUSIONS

Our findings revealed attenuated functional homotopy in both NPSLE and non-NPSLE groups compared to the HC group, which appeared to be more severe in patients with comorbid neuropsychiatric lupus. Interhemispheric homotopy dysconnectivity may participate in the neuropathology of anxiety symptoms in SLE.

Altered Functional Brain Network in Systemic Lupus Erythematosus Patients Without Overt Neuropsychiatric Symptoms Based on Resting-State Functional Magnetic Resonance Imaging and Multivariate Pattern Analysis

Objective: This study aims to investigate the alterations in functional brain network in systemic lupus erythematosus patients without overt neuropsychiatric symptoms [neuropsychiatric systemic lupus erythematosus (non-NPSLE)] from the perspective of degree centrality (DC) and functional connectivity (FC) using resting-state functional magnetic resonance imaging (MRI) and multivariate pattern analysis (MVPA) approach.

Methods: DC analysis was performed based on the resting-state functional MRI data derived from 47 non-NPSLE patients and 47 healthy controls (HCs). Nodes with abnormal DC were utilized as seeds for further FC analysis. The correlation between MRI variables and clinical or neuropsychological data was analyzed using Pearson correlation analysis. Finally, MVPA classification based on DC was performed.

Results: When compared with the HCs, the non-NPSLE patients exhibited remarkably higher DC in the bilateral hippocampus (HIP), right insula (INS), and lower DC in the left superior parietal gyrus. Furthermore, the patients displayed significantly higher FC between the left HIP and the left INS/left dorsolateral middle frontal gyrus/left supramarginal gyrus and higher FC between the right HIP and the right middle temporal gyrus/right dorsolateral middle frontal gyrus/right dorsolateral inferior frontal gyrus/right supramarginal gyrus (all imaging variables mentioned earlier underwent cluster-level false discovery rate corrections, the voxel threshold was p < 0.001, cluster threshold was p < 0.05). Correlation analysis revealed significantly negative correlations between DC values of the right INS and disease activity and the DC values of the right HIP and the Montreal Cognitive Assessment scores. The accuracy, sensitivity, and specificity of MVPA classification based on DC were 72.34, 63.83, and 80.85%, respectively. The most discriminative power brain regions were chiefly located within the temporal, parietal, and frontal regions.

Conclusion: Patients with non-NPSLE exhibited abnormal DC and FC in the brain network. MVPA based on DC possessed commendable classification ability. Our study may provide a novel perspective on the neuropathological mechanisms underlying subclinical brain damage in non-NPSLE.

Formal neurocognitive function and anti-N-methyl-D-aspartate receptor antibodies in paediatric lupus

Objective

SLE is a chronic multisystem autoimmune inflammatory disease impacting a number of organs, including the central nervous system (CNS). The pathophysiology of CNS lupus is multifactorial, making diagnosis problematic. Neurocognitive (NC) testing and specific biomarkers to identify the development of neuropsychiatric (NP) symptoms in lupus are needed. Paediatric patients with SLE have high incidence of NP disease. While serum anti-N-methyl-D-aspartate receptor (NMDAR) antibodies have shown promise as a biomarker of NP in adults with SLE, much less is known with regard to paediatric patients with SLE.

Methods

We performed a cross-sectional study in paediatric patients with SLE. Serum NMDAR antibodies were measured and compared with levels in patients with juvenile idiopathic arthritis (JIA). Formal NC testing was performed in accordance with the Childhood Arthritis & Rheumatology Research Alliance neuropsychological core test battery. NC functioning was compared in the two groups and with NMDAR antibody levels.

Results

Serum NMDAR antibody levels were significantly higher in paediatric patients with SLE compared with patients with JIA. There were no significant correlations between NMDAR antibody levels and any measure of NC functioning. In an exploratory examination of anti-ribosomal P (RibP) antibody and NC functioning in a subset of patients with SLE, RibP antibody-positive patients exhibited worse scores for Verbal Memory Index and Design Fluency Test Switching compared with RibP antibody-negative patients. A globally significant association between disease status and NC functioning was observed. Specifically, patients with SLE had lower scores compared with patients with JIA for full-scale IQ, letter–word recognition, reading fluency and calculation skills after adjusting for multiple comparisons.

Conclusion

These collective results suggest that although serum NMDAR may serve as a biomarker, formal NC testing is superior in identifying paediatric patients with SLE with NP manifestations. RibP also may potentially serve as a biomarker of NP manifestations in paediatric patients with SLE. Additional and longitudinal studies are needed.