COGNITIVE DEFICITS IN SYSTEMIC LUPUS ERYTHEMATOSUS

Systemic lupus erythematosus patients with past neuropsychiatric involvement are associated with worse cognitive impairment: a longitudinal study

Longitudinal studies on cognitive impairment in patients with past history of neuropsychiatric lupus (NPSLE) are scant. In this study, NPSLE patients and matched disease and healthy controls were examined with a full battery of neuropsychological tests that covered eight cognitive domains at two time-points 12 months apart. Confounders, including depressive and anxiety symptoms, were measured by the Hospital Anxiety and Depression Scale. Eighteen NPSLE, 18 patients with systemic lupus erythematosus (SLE) who had no previous cerebral involvement (non-NPSLE) and 16 healthy subjects were recruited. NPSLE patients consistently reported more cognitive and anxiety symptoms than non-NPSLE patients over both time-points. NPSLE patients had significantly worse memory, simple and complex attention compared to non-NPSLE patients, among which memory remained significantly impaired after adjustment for confounders. NPSLE patients demonstrated a trend of higher raw scores of some neurocognitive tests upon re-evaluation over 12 months, but NPSLE patients did not demonstrate any practice effect. In conclusion, NPSLE patients had significantly worse and persistently impaired memory and learning deficits compared to non-NPSLE patients over the 12-month re-assessment period.

Symptoms of attention deficit hyperactivity disorder in patients with systemic lupus erythematosus

OBJECTIVES

Cognitive function and mood disturbance are common in patients with systemic lupus erythematosus (SLE). This study aims to examine whether SLE patients have more features of adult attention deficit hyperactivity disorder (ADHD) and their relation to anxiety and depressive symptoms.

METHODS

Symptoms and clinically significant items of the inattention and hyperactivity/impulsivity domains of ADHD were examined in Part A and Part B by the screening instrument of the ADHD Self-Reported Scale (ASRS), respectively. Anxiety and depressive symptoms were measured by HADS-A and HADS-D, respectively.

RESULTS

There were no differences in symptom scores of inattention and hyperactivity/impulsivity between inactive SLE patients (n = 117) and age- and sex-matched controls (n = 64). However, SLE patients had more clinically significant items in the inattention domain compared with controls (p = 0.006), particularly among those who had previous cerebral involvement (p = 0.004). Patients who had psychiatric diseases had more clinically significant items in the hyperactivity/impulsivity domain (p = 0.006). Possible ADHD was found in 7.7% of SLE and 6.3% of healthy individuals (p = 1.00) by the screening tool. Patients with higher inattention symptom scores were more likely to be unemployed but not for duration of education and smoking habit. Anxiety and depressive symptoms correlated with ADHD symptoms. HADS-A was an independent predictive factor for clinically significant symptoms of inattention (p < 0.001) and hyperactivity/impulsivity (p = 0.04) by logistic regression.

CONCLUSION

Inactive SLE patients, particularly those who had previous cerebral lupus, had more clinically significant symptoms of inattention but not hyperactivity/impulsivity reflecting underlying cognitive impairment. Anxiety and depressive symptoms were common confounders for ADHD-like symptoms.

Comparison of a self-report and performance-based test of disability in people with systemic lupus erythematosus

PURPOSE

The purpose of this study was to examine functional ability in people with SLE by comparing a self-report and a performance-based test.

METHOD

Fifteen women with SLE and 15 healthy controls participated in this study. Participants completed a self report of daily living skills, the Health Assessment Questionnaire (HAQ). Actual performance during activities of daily living was evaluated with the Assessment of Motor and Process Skills (AMPS). Measures of cognition and disease activity were also collected.

RESULTS

HAQ scores of the participants with SLE indicated only very mild disability while scores on the AMPS indicated ineffective skill performance and potential safety risks. In the participants with SLE, cognitive status correlated significantly with the processing component (r(s) = 0.62, p < 0.05) and disease severity correlated with the motor component of the AMPS (r(s) = 0.84, p < 0.001). The HAQ did not correlate with the AMPS.

CONCLUSIONS

This study suggests that cognitive deficits were more related to scores on the performance-based test of functional ability rather than the self-report. The performance-based test appeared to provide information that was not gained through self-report and measures of disease activity and gross cognition.

Autoantibody-mediated neuroinflammation: pathogenesis of neuropsychiatric systemic lupus erythematosus in the NZM88 murine model

Autoantibodies play an important role in central nervous system manifestations of neuropsychiatric systemic lupus erythematosus (NPSLE). Previous studies have shown that the lupus-prone NZM88 strain has major neural deficits and high titers of serum IgG to brain antigens. ELISA was performed to detect the presence of IgG in different brain regions of NZM88 mice and to compare the levels with NZM2758 mice and control strains (NZW and BALB/c). There was a substantial increase of IgG in the substantia nigra (SN) and hypothalamus (HT) of brains from NZM88 mice compared to control NZW and BALB/c mice, whereas NZM2758 mice had more IgG in the cortex. The increased presence of IgG in the NPSLE-prone NZM88 mouse brain was paralleled by increased TNF-alpha and IL-12 in the SN and HT regions; significantly elevated expression of MHC Class-II was also observed in the SN of NZM88 mice and cortex of NZM2758 mice. A co-culture system of dopaminergic neurons and microglia was used to demonstrate that NZM88 sera modifies dopaminergic cell activity only in the presence of microglia and that TNF-alpha is synthesized and released in this co-culture. This study demonstrates a functional link between the autoantibodies, the activation of microglia, and neuronal function associated dopamine production, which is suggested to be causally related to the predominant NPSLE syndromes.

Central nervous system involvement in systemic connective tissue diseases

Systemic connective tissue diseases can affect the brain, meninges, spinal cord, cranial and peripheral nerves. Different pathogenic mechanisms, particularly autoantibody or T-cell mediated lesions, appear to be involved. The neurological manifestations of the connective tissue diseases and their diagnostic possibilities including newer imaging techniques are reviewed. Early recognition of neurological abnormalities can help in the differential diagnosis and in defining the underlying disease in order to initiate treatment and prevent progression of lesion or cognitive function loss.

Proliferating brain cells are a target of neurotoxic CSF in systemic autoimmune disease

Brain atrophy, neurologic and psychiatric (NP) manifestations are common complications in the systemic autoimmune disease, lupus erythematosus (SLE). Here we show that the cerebrospinal fluid (CSF) from autoimmune MRL-lpr mice and a deceased NP-SLE patient reduce the viability of brain cells which proliferate in vitro. This detrimental effect was accompanied by periventricular neurodegeneration in the brains of autoimmune mice and profound in vivo neurotoxicity when their CSF was administered to the CNS of a rat. Multiple ionic responses with microfluorometry and protein peaks on electropherograms suggest more than one mechanism of cellular demise. Similar to the CSF from diseased MRL-lpr mice, the CSF from a deceased SLE patient with a history of psychosis, memory impairment, and seizures, reduced viability of the C17.2 neural stem cell line. Proposed mechanisms of cytotoxicity involve binding of intrathecally synthesized IgG autoantibodies to target(s) common to different mammalian species and neuronal populations. More importantly, these results indicate that the viability of proliferative neural cells can be compromised in systemic autoimmune disease. Antibody-mediated lesions of germinal layers may impair the regenerative capacity of the brain in NP-SLE and possibly, brain development and function in some forms of CNS disorders in which autoimmune phenomena have been documented.

Contributions of Observational Cohort Studies in Systemic Lupus Erythematosus: The University of Toronto Lupus Clinic Experience

This article uses the University of Toronto Lupus Cohort to illustrate the benefits of observational cohort studies in generating important new knowledge in chronic disease such as systemic lupus erythematosus.

Cognitive dysfunction and antiphospholipid antibodies in systemic lupus erythematosus

Nervous system involvement in systemic lupus erythematosus (SLE) is typically diagnosed on the basis of clinical psychiatric and/or neurologic syndromes (NPSLE). Neuropsychological tests can be used to assess nervous system integrity even in the absence of major NP syndromes. Their application has uncovered significant cognitive dysfunction, ranging from mild to severe, in a sizeable proportion of SLE patients irrespective of clinical NP status. Cognitive dysfunction has now been accepted as a bona fide manifestation of NPSLE. The heterogeneity of clinical NPSLE manifestations is paralleled by the diversity of cognitive deficits reported in different studies and within different patients. The success of attempts to explain these deficits on the basis of potential pathogenetic mechanisms, such as antibrain antibodies and proinflammatory cytokines, has been uneven. To date, the most robust findings have emerged in relation to antiphospholipid antibodies, which carry with them important therapeutic implications.

Central nervous system involvement in systemic lupus erythematosus patients without overt neuropsychiatric manifestations

OBJECTIVE

To verify whether features of CNS involvement can be detected in SLE patients without overt neuropsychiatric manifestations.

METHODS

114 SLE patients who had never received a diagnosis of neuropsychiatric lupus (never-NPSLE) were studied and compared to 65 SLE patients with known neuropsychiatric involvement (NPSLE). The study relied on evaluation of neurocognitive functions by means of a battery of neuropsychological tests, on psychiatric and neuropsychological assessments and on neuroimaging studies (computed tomography, magnetic resonance, single photon emission computed tomography (SPECT)).

RESULTS

Clinical features, including disease duration/activity and pharmacological therapy, of never-NPSLE and NPSLE patients were similar. Short-term and long-term memory, visuo-spatial and verbal information processing were similarly compromised in never-NPSLE and in NPSLE patients; only attention was significantly more compromised in NPSLE patients. Psychiatric morbidity was higher than expected in never-NPSLE patients, although less than in the control neuropsychiatric group. Ischemic lesions, multiple small high intensity lesions and cortical atrophy, detected by CT and MR scans, as well as abnormal SPECT were also frequently detected in never-NPSLE patients. Interestingly, left parietal and occipital area hypoperfusion by SPECT was significantly more frequent in the patients with impaired visuo-spatial intelligence and short-term memory.

CONCLUSIONS

Most abnormalities detected by available diagnostic tools and characteristics of neuropsychiatric SLE are also present in non-symptomatic patients. They may derive from an unexpected widespread involvement of the CNS and are not per se sufficient, in the absence of clinical manifestations, for a diagnosis of neuropsychiatric SLE.

Analysis of exploratory eye movement in a patient with lupus psychosis

The psychiatric and cognitive condition of a patient with lupus psychosis was evaluated. Using a device that detects the corneal reflection of infrared light, the patterns of eye tracking movements were recorded before the onset of lupus psychosis, after remission, and again 1 year later. Electroencephalographic findings and cerebrospinal fluid levels of both interferon alpha and interleukin-6 were also obtained longitudinally. Electroencephalographic findings and clinical signs were correlated to the levels of interferon alpha in cerebrospinal fluid. Analysis of exploratory eye movements revealed marked decreases in the number of eye fixation, mean eye-scanning length and total eye-scanning length. Even though the lupus psychosis resolved and the electroencephalographic findings became normal, the eye movement patterns showed remaining deterioration. It was concluded that analysis of exploratory eye movements in patients with systemic lupus erythematosus may be useful in diagnosing lupus psychosis, and may also present a diagnostic clue to subclinical lupus psychosis.

Neurobehavioral alterations in autoimmune mice

Inbred MRL, NZB and BXSB strains of mice spontaneously develop a systemic, lupus-like autoimmune disease. The progress of autoimmunity is accompanied with a cascade of behavioral changes, most consistently observed in tasks reflective of emotional reactivity and the two-way avoidance learning task. Given the possibility that behavioral alterations may reflect a detrimental consequence of autoimmune-inflammatory processes and/or an adaptive response to chronic malaise, they are tentatively labeled as autoimmunity-associated behavioral syndrome (AABS). It is hypothesized that neuroactive immune factors (pro-inflammatory cytokines, brain-reactive antibodies) together with endocrine mediators (corticotropin-releasing factor, glucocorticoids) participate in the etiology of AABS. Since AABS develops natively, and has a considerable face and predictive validity, and since the principal pathway to autoimmunity is known, AABS may be a useful model for the study of CNS involvement in human autoimmune diseases and by extension, for testing autoimmune hypotheses of several mental disorders (major depression, schizophrenia, Alzheimer's disease, autism and AIDS-related dementia).

Effect of cyclophosphamide on leukocytic infiltration in the brain of MRL/lpr mice

Neuropsychiatric manifestations are a poorly understood and potentially life-threatening complication of systemic lupus erythematosus (SLE). MRL/lpr mice spontaneously develop a lupus-like syndrome which is similar to the human disease in many respects, including behavioural abnormalities. Our previous findings indicated that the age at which infiltration of immune cells into the choroid plexus is first observed coincides with the appearance of behavioural dysfunction in MRL/lpr mice. This present study quantified leukocyte infiltration in relation to prolonged administration of cyclophosphamide (CY), a treatment effective in preventing some behavioural deficits. Compared to MRL +/+ controls, saline-treated MRL/lpr mice had significantly more CD45-positive cells (leukocytes) and CD45R-positive (B) cells in the choroid plexus and in the brain parenchyma. A six week course of CY (100 mg/kg i.p.) significantly reduced the infiltration of CD45, but not of CD45R-positive cells into the choroid plexus of the MRL/lpr substrain. In addition, the presence of leukocytes correlated positively with measures on one behavioural test (floating in the forced swim test) but not on another test (novel object test). These findings suggest that CY treatment has a differential effect on the infiltration of leukocyte subtypes and strengthen the hypothesis that some abnormal behaviour in MRL/lpr mice may be related to the presence of immunocompetent cells in the brain.

Psychiatric aspects of rheumatology

The rheumatic diseases pose significant and challenging problems for the consulting psychiatrist because of their multifaceted clinical features. Consideration must be given to the complexity of the social system in which the patient lives, the rheumatologist-patient relationship, the losses incurred by the illness, immunologic vulnerability to opportunistic infections, the effects of concurrent medical treatments (especially drug treatments), and any antecedent pathologic conditions. This article examines the clinical and treatment highlights of two representative rheumatologic diseases: rheumatoid arthritis and systemic lupus erythematosus.

Psychoneuroimmunology of autoimmune disorders

The interactions between the immune system and psychological states are both intricate and intriguing. Research at a molecular level has thrown considerable light on the previously ill-defined area of psychoneuroimmunology. In this report, we explore the psychoneuroimmunology of autoimmune disorders, particularly rheumatoid arthritis and lupus erythematosus. Animal models of these diseases have provided a particularly useful window on complex psychoneuroimmunological interactions. Observations about the effect of stress on the onset and course of autoimmune disorders has added to our understanding of psychoneuroimmunological interactions. These interactions are bi-directional, as reflected in the autoimmune-mediated neuropsychiatric manifestations of systemic lupus. Exploring the role of various neurotransmitters and neuromodulators in the stress response may have important therapeutic implications for autoimmune disorders.

Nervous system lupus: pathogenesis and rationale for therapy

Several different pathogenic mechanisms appear to be involved in CNS lupus. These include: B-cell/autoantibody-mediated nervous system compromise; immune complex deposition and vasculitis; microthrombosis and vasculopathy; aberrant MHC Class II antigen expression with T-cell mediated disease (multiple-sclerosis model); and, cytokine-induced brain inflammation. These processes are not mutually exclusive: there exist in vitro and in vivo models for each of these. A number of autoantibodies, especially those with specificities for shared neuronal/lymphocyte antigens, are associated with certain forms of cognitive dysfunction or overt nervous system manifestations. In MRL/lpr mice, lymphoid infiltrates in the brain parenchyma are related to a neurobehavioural dysfunction which develops very early in the course of autoimmune disease. Recent results, both in animal models and in human studies on the therapeutic effects of corticosteroids, immunosuppressive drugs or anticoagulants on clinical and subclinical manifestations of CNS lupus are highlighted in an attempt to develop a rationale for intervention based upon presumed pathogenesis.

Corticosteroids and neuropsychological functioning in patients with systemic lupus erythematosus

OBJECTIVE

This study was designed to assess the effects of corticosteroids on select aspects of nervous system functioning, specifically, cognition and mood, as well as disease-related symptoms in individual patients with mild systemic lupus erythematosus (SLE) and mild neuropsychiatric (NP) symptoms.

METHODS

Ten women who had not been taking corticosteroids for at least 6 months were selected from a referral-based lupus clinic to participate in an N of 1 double-blind, controlled trial consisting of 3 randomly assigned drug/placebo pairings, with a drug dose of 0.5 mg/kg of prednisone daily.

RESULTS

Analysis of variance on the group data yielded significant positive drug effects for cognition (P = 0.02), mood (P = 0.003), and SLE symptom ratings (P = 0.0002). Drug efficacy was also evaluated by an objective decision rule, which yielded evidence of overall drug benefit in 5 of the 8 patients who completed the trial, and a deleterious drug effect in 1 patient. Posttrial clinical results indicated that for the 8 women who completed the trial, "acceptable" decisions, leading to remission of SLE symptoms or appropriate withholding of steroids, were made on the basis of this rule.

CONCLUSION

Improvement in cognition, mood, and/or SLE symptom ratings can be observed following brief exposure to relatively low doses of corticosteroids in individual women with mild SLE; these persist over repeated drug exposure. The current application of N of 1 methodology represents the first systematic study of steroid efficacy in central nervous system (CNS)-related problems in SLE. The results can now be applied to the design of randomized, controlled trials of the effects of corticosteroids on CNS function in SLE.