Treatment of cognitive impairment in multiple sclerosis: is the use of acetylcholinesterase inhibitors a viable option?

Postulating the possible cellular signalling mechanisms of antibody drug conjugates in Alzheimer's disease

Alzheimer's disease (AD) is one of the most common neurodegenerative disorders in the world. Although the basic pathology of the disease is elucidated, it is difficult to restore or prevent the worsening of neurodegeneration and its symptoms. Antibody and small molecule-based approaches have been studied and are in study individually, but a combined approach like conjugation has not been performed to date. The conjugation between antibodies and drugs which are already used for Alzheimer's treatment or developed specifically for this purpose may have better efficacy and dual action in mitigating Alzheimer's disease. A probable mechanism for antibody-drug conjugates in Alzheimer's disease is discussed in the present review.

Pharmacotherapy in multiple sclerosis-induced cognitive impairment: A systematic review and meta-analysis

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) commonly complicated by cognitive impairment. Unfortunately, no medical therapy has been proved to improve cognitive problems in these patients. This meta-analysis investigated the effectiveness of different categories of drugs on the minimal assessment of cognitive function in MS (MACFIMS)-related tasks outcome in MS patients. To this end, a systematic evaluation was conducted using PubMed, Google Scholar, and Scopus databases. Among a total of 128 publications, 31 studies met our inclusion criteria, and 22 included in the meta-analysis. We found that symbol digit modalities test (SDMT), paced auditory serial addition test (PASAT), controlled oral word association test (COWAT), and California verbal learning test (CVLT) were the most frequently reported tasks in included studies. The frequently reported drugs were classified into five main groups of acetylcholine esterase inhibitors, CNS stimulants, fampridine, herbal remedies, and miscellaneous. Overall heterogeneity of the studies was modest. The treatments did not affect cognitive function in any of the tasks (p>0.05). However, in subgroup analysis, we found significant improvement in SDMT task outecomes after treatment by fampridine (0.283 SMD, 95%CI, 0.015 to 0.550, p = 0.039, I2=11.7%). Our meta-analysis highlighted that the currently proposed therapeutic agents had no beneficial effects on the alleviation of MS-induced cognitive impairment.

Effect of Donepezil on Cognitive Impairment, Quality of Life, and Depression in Multiple Sclerosis Patients: A Randomized Clinical Trial

Background:

Cognitive impairment is one of the debilitating consequences of multiple sclerosis (MS) with negative effects on daily life, individual and social activities, quality of life (QOL), and depression. No approved medication is introduced so far for affected individuals. We aimed to evaluate the efficacy of donepezil on cognitive performance, QOL, and depression in MS.

Methods:

This is a double-blinded randomized clinical trial conducted on 100 patients with MS during 2018. Patients were assessed prior to intervention abbreviated mental test (AMT), prospective and retrospective mental questionnaire (PRMQ), everyday memory questionnaire (EMQ), digit span test, Beck depression inventory (BDI), and MSQOL questionnaire. Then patients were randomly divided into two groups of treatment (daily regimen of 10 mg donepezil) and placebo for 3 months. Subjects were reassessed using the same instruments at the end of intervention.

Results:

Fifty patients remained in each group at the end of study. The mean age in donepezil and placebo groups was 31.9 ± 5.89 and 30.65 ± 5.43 years, respectively. EMQ, PRMQ, digit span test, MSQOL, and depression scores improved following donepezil therapy (P < 0.001) while no statistically significant difference was found in the placebo group (P > 0.05). Comparison of two groups also showed more favorable scores in donepezil group with respect to all assessment tools (P < 0.001).

Conclusions:

Donepezil could effectively improve cognitive impairment in MS patients. Also, its positive effect on QOL and depression could result in a smaller number of interventions in this group of patients.

Evaluation of cognitive rehabilitation on the cognitive performance in multiple sclerosis: A randomized controlled trial

Background

Multiple sclerosis (MS) can involve cognitive entities, including memory, attention, performance, and information processing. Furthermore, MS causes depression and negatively affects the quality of life (QOL). This study was aimed to assess the efficacy of cognitive rehabilitation on cognitive entities of MS patients.

Materials and Methods

This is a clinical trial study conducted on 56 MS patients in 2016-2017. Patients were randomly divided into two Groups of A (cognitive rehabilitation) and B (control group). Patients were evaluated in terms of memory, attention, QOL, and depression. Questionnaires included Abbreviated Mental Test, Prospective and Retrospective Memory Questionnaire, Everyday Memory Questionnaire, Digit Spam test for attention assessment, QOL-54 questionnaire, and Second version of Beck questionnaire assessing depression. They were filled through an interview before the study initiation, and then, the intervention group underwent ten sessions of cognitive rehabilitation and questionnaires refilled within 3 months after study initiation. Outcomes of the two groups were compared.

Results

Memory, attention, QOL, and depression improved significantly following the intervention in cases (P < 0.05), while no significant change was observed among controls (P > 0.05). Comparison of cases and controls in the second evaluation showed a significant difference between cases and controls (P < 0.05).

Conclusion

Ten sessions of cognitive rehabilitation could significantly improve MS patients' cognitive performance. Moreover, this approach affected their QOL and sense of depression in a decisive trend. It can be concluded that cognitive rehabilitation can successfully affect numerous aspects of MS patients, while numerous medical therapies may be required for treatment of each mere aspect. Further evaluations are strongly recommended.

Pharmacological and Non-pharmacological Therapies of Cognitive Impairment in Multiple Sclerosis

Background

Cognitive impairment is one of the most important clinical features of neurodegenerative disorders including multiple sclerosis (MS). Conducted research shows that up to 65 percent of MS patients have cognitive deficits such as episodic memory, sustained attention, reduced verbal fluency; however, the cognitive MS domain is information processing speed. It is the first syndrome of cognitive dysfunction and the most widely affected in MS. Occasionally these impairments occur even before the appearance of physical symptoms.

Methods

Therefore, this review focused on the current status of our knowledge about possible methods of treatment cognitive impairment in MS patients including novel strategies. Research and online content was performed using Medline and EMBASE databases.

Results

The most recent research suggests that cognitive impairment is correlated with brain lesion volume and brain atrophy. The examination of the cognitive impairment is usually based on particular neuropsychological batteries. However, it can be not enough to make a precise diagnosis. This creates a demand to find markers that might be useful for identifying patients with risk of cognitive impairment at an early stage of the disease. Currently the most promising methods consist of neuroimaging indicators, such as diffusion tensor imaging, the magnetization transfer ratio, and N-acetyl aspartate levels. Diagnosis problems are strictly connected with treatment procedures. There are two main cognitive therapies: pharmacological (disease modifying drugs (DMD), symptomatic treatments) and non-pharmacological interventions that are focused on psychological and physical rehabilitation. Some trials have shown a positive association between physical activity and the cognitive function.

Conclusion

This article is an overview of the current state of knowledge related to cognition impairment treatment in MS. Additionally, novel strategies for cognitive impairments such as cryostimulation and other complementary methods are presented.

NF-κB-regulated microRNA-574-5p underlies synaptic and cognitive impairment in response to atmospheric PM2.5 aspiration

Background

PM_2.5 (particulate matter ≤ 2.5 μm) is one of the leading environmental risk factors for the global burden of disease. Whereas increasing evidence has linked the adverse roles of PM_2.5 with cardiovascular and respiratory diseases, limited but growing emerging evidence suggests that PM_2.5 exposure can affect the nervous system, causing neuroinflammation, synaptic dysfunction and cognitive deterioration. However, the molecular mechanisms underlying the synaptic and cognitive deficits elicited by PM_2.5 exposure are largely unknown.

Methods

C57BL/6 mice received oropharyngeal aspiration of PM_2.5 (1 and 5 mg/kg bw) every other day for 4 weeks. The mice were also stereotaxically injected with β-site amyloid precursor protein cleaving enzyme 1 (β-secretase, BACE1) shRNA or LV-miR-574-5p lentiviral constructs in the absence or presence of PM_2.5 aspiration at 5 mg/kg bw every other day for 4 weeks. Spatial learning and memory were assessed with the Morris water maze test, and synaptic function integrity was evaluated with electrophysiological recordings of long-term potentiation (LTP) and immunoblot analyses of glutamate receptor subunit expression. The expression of α-secretase (ADAM10), BACE1, and γ-secretase (nicastrin) and the synthesis and accumulation of amyloid β (Aβ) were measured by immunoblot and enzyme-linked immunosorbent assay (ELISA). MicroRNA (miRNA) expression was screened with a microRNA microarray analysis and confirmed by real-time quantitative reverse transcription PCR (qRT-PCR) analysis. Dual-luciferase reporter gene and chromatin immunoprecipitation (ChIP) analyses were used to detect the binding of miR-574-5p in the 3’UTR of BACE1 and NF-κB p65 in the promoter of miR-574-5p, respectively.

Results

PM_2.5 aspiration caused neuroinflammation and deteriorated synaptic function integrity and spatial learning and memory, and the effects were associated with the induction of BACE1. The action was mediated by NF-κB p65-regulated downregulation of miR-574-5p, which targets BACE1. Overexpression of miR-574-5p in the hippocampal region decreased BACE1 expression, restored synaptic function, and improved spatial memory and learning following PM_2.5 exposure.

Conclusions

Taken together, our findings reveal a novel molecular mechanism underlying impaired synaptic and cognitive function following exposure to PM_2.5, suggesting that miR-574-5p is a potential intervention target for the prevention and treatment of PM_2.5-induced neurological disorders.

Electronic supplementary material

The online version of this article (10.1186/s12989-017-0215-3) contains supplementary material, which is available to authorized users.

A structural MRI study of cholinergic pathways and cognition in multiple sclerosis

Background

White matter hyperintensities (WMH) in the cholinergic pathways are associated with cognitive performance in Alzheimer's disease. This study aimed to evaluate the relationship between the volume reduction of cholinergic pathways and cognitive function in patients with multiple sclerosis (MS).

Methods

Thirty-two MS patients underwent a brain MRI and cognitive measurements including the Mini-Mental State Examination (MMSE) and the Japanese version of the Montreal Cognitive Assessment (MoCA-J). The extent of WMH within the cholinergic pathways was assessed using the Cholinergic Pathways Hyperintensities Scale (CHIPS). Computerized WMH volumes were also obtained. FreeSurfer was used to measure regional volumes including the cortical and subcortical volumes. The correlations among the CHIPS, the WMH volume, and the clinical data were assessed, in addition to the correlations between the cognitive scores and regional volumes measured by FreeSurfer.

Results

The CHIPS score and the WMH volume were strongly positively correlated with each other (r = 0.87, P < 0.001). The CHIPS score had significantly negative correlations with the MMSE (r = - 0.49, P = 0.003) and the MoCA-J (r = - 0.47, P = 0.005) results. The WMH volume had significantly negative correlations with the MMSE (r = - 0.54, P = 0.001) and the MoCA-J (r = - 0.57, P < 0.001) results. In the analysis by FreeSurfer, both the MMSE and MoCA-J scores had significant positive correlations only with the volume of the corpus callosum.

Conclusions

The CHIPS score tended to be less sensitive to the WMH volume in cognitive function evaluation, although the difference did not reach the level of statistical significance. Thus the CHIPS method may not be as effective in MS patients.

Cognitive Impairment in Multiple Sclerosis

Multiple sclerosis (MS) is a socially significant immune-mediated disease, characterized by demyelination, axonal transection and oligodendropathy in the central nervous system. Inflammatory demyelination and neurodegeneration lead to brain atrophy and cognitive deficit in up to 75% of the patients. Cognitive dysfunctions impact significantly patients’ quality of life, independently from the course and phase of the disease.

The relationship between pathological brain findings and cognitive impairment is a subject of intensive research.

Summarizing recent data about prevalence, clinical specificity and treatment of cognitive disorders in MS, this review aims to motivate the necessity of early diagnosis and complex therapeutic approach to these disturbances in order to reduce the social burden of the disease.

The BICAMS Battery for Assessment of Lithuanian-Speaking Multiple Sclerosis Patients: Relationship with Age, Education, Disease Disability, and Duration

Background

Assessment of cognitive impairment (CI) in multiple sclerosis (MS) patients is very useful, but it requires time-consuming expert evaluation with specialized materials. The Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) was created as a brief and specific instrument for the evaluation of CI.

The aims of this study were to assess the cognitive status of MS patients by using the Lithuanian version of BICAMS, to evaluate the test-retest reliability of the Lithuanian version of BICAMS, and to measure the impact of CI on disability and duration of MS.

Material/Methods

We enrolled 50 MS patients and 20 cognitively normal control subjects, matched for age, gender, and level of education. Cognitive functions were assessed by the BICAMS tests, which include the Symbol Digit Modalities Test, the Brief Visuospatial Memory Test Revised, and the California Verbal Learning Test, 2^nd edition.

Results

MS patients performed significantly worse than controls on the 3 neuropsychological tests of BICAMS (p<0.001). Younger and intellectually employed persons performed significantly better on these tests than older persons, manual workers, or unemployed persons (p<0.05). MS patients with higher disability scores tended to perform worse on the tests (p<0.05), but we found no relationship between BICAMS test scores and the duration of the disease or relapse rate (p>0.05). Test-retest reliability was excellent for all 3 subtests (r>0.8, p<0.05).

Conclusions

Our study shows that BICAMS is a valid and acceptable cognitive assessment tool that can be recommended for routine use in Lithuania for assessing patients with MS.

Evaluating Neurocognitive Deficits in Patients With Multiple Sclerosis Via a Brief Neuropsychological Approach

Recent research demonstrates neurocognitive deficits are present early in the sequelae of multiple sclerosis (MS). This is an important consideration given the functional activities of daily living, such as employment, that can be impacted by neurocognitive dysfunction. This study investigated the utility of a brief neuropsychological battery, the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), to evaluate neurocognitive deficits in patients with MS and to examine the relationship between a measure of functional disability (Expanded Disability Status Scale [EDSS]) and the RBANS. Participants were 49 patients with MS (Mage = 45.39 years) who completed the RBANS as part of a neuropsychological assessment and 49 demographically matched healthy controls (Mage = 45.39 years). Multivariate analysis of variance revealed that the two groups differed on the RBANS. Descriptive discriminant analysis indicated the groups differed on domains of attention, language, immediate memory, and delayed memory. EDSS scores were a good predictor of neurocognitive dysfunction in patients with advanced disability but not for patients with mild disability. The RBANS seems to be effective in identifying cognitive dysfunction in patients with MS, and caution should be used in extrapolating cognitive deficits for patients with low EDSS scores.

Factors affecting employment among informal caregivers assisting people with multiple sclerosis

The objective of this study was to identify characteristics of informal caregivers, caregiving, and the people with multiple sclerosis (MS) receiving assistance that are associated with reduced caregiver employment. Data were collected during telephone interviews with 530 MS caregivers, including 215 employed caregivers, with these survey data analyzed using logistic regression. Poorer cognitive ability by the care recipient to make decisions about daily tasks and more caregiving hours per week predicted reduced caregiver employment. Better physical health domains of caregiver quality of life were associated with significantly lower odds of reduced employment. Health professionals treating informal caregivers, as well as those treating people with MS, need to be aware of respite, support, and intervention programs available to MS caregivers and refer them to these programs, which could reduce the negative impact of caregiving on employment.

Biological markers in cerebrospinal fluid for axonal impairment in multiple sclerosis: acetylcholinesterase activity cannot be considered a useful biomarker

An impairment of the cholinergic system activity has been demonstrated in multiple sclerosis (MS). The correlation between the cholinergic system and the cognitive dysfunction in MS has led to studies on the use of acetylcholinesterase inhibitors (AChEI). The acetylcholinesterase (AChE), essential enzyme for the regulation of turnover of acetylcholine, can be considered the most important biochemical indicator of cholinergic signaling in the nervous system. Besides its catalytic properties, AChE has a crucial role in the regulation of the immune function. Based on the role of the AChe in the regulation of cholinergic signaling in the nervous system, the aim of the present study is to evaluate the activity of AChE in different pathological conditions: MS, other inflammatory neurological disorders (OIND) and non-inflammatory neurological disorders (NIND). We measured AChE activity in CSF samples obtained from 34 relapsing-remitting MS patients and, as controls, 40 patients with other inflammatory neurological disorders (OIND) and 40 subjects with other non-inflammatory neurological disorders (NIND). Fluorimetric detection of the AChE in MS patients and in the controls showed no statistically significant differences: 1.507 ± 0.403 nmol/ml/min in MS patients, 1.484 ± 0.496 nmol/ml/min in OIND and 1.305 ± 0.504 nmol/ml/min in NIND. Similar results were obtained in another recent study, using a different method. Further studies must be conducted on a larger number of patients, with different degrees of cognitive impairment. However, AChE measured in CSF can probably not be considered a useful biomarker for the assessment of the functional alterations of cholinergic system in pathological conditions.

Randomised multicentre trial on safety and efficacy of rivastigmine in cognitively impaired multiple sclerosis patients

BACKGROUND

Cognitive decline has been recognised as a frequent symptom in multiple sclerosis (MS). Cholinesterase inhibitors (ChEIs) are employed for the treatment of Alzheimer's disease, but there is some evidence that ChEIs might also be effective in MS patients with cognitive deficits, particularly deficits of memory function.

OBJECTIVE

The aim of this study was to evaluate efficacy on memory function and safety of the ChEI rivastigmine in MS patients with cognitive deficits as measured by the change from baseline of the total recall score of the selective reminding test (SRT) after 16 weeks of treatment.

METHODS

Efficacy and safety of rivastigmine were analysed in a 16-week, multicentre, double-blind, randomised, placebo-controlled study, followed by an optional one-year open-label treatment phase. Effects of rivastigmine and placebo were compared by an analysis of covariance.

RESULTS

In total, 86 patients were enrolled. Patients who received rivastigmine (n = 43) showed a non-significant increase in total recall score (sum of all words immediately recalled over all six trials) over placebo (n = 38) after 16 weeks of treatment (p = 0.2576). Other outcome measures provided no evidence supporting benefits of rivastigmine. Treatment with rivastigmine was well tolerated.

CONCLUSIONS

With the results of this study, the need for an effective therapy in cognitively impaired MS patients is still required. Thus, intensive and continued clinical research is required to explore therapeutic options for cognitive deficits in MS patients.

Cognitive dysfunction in multiple sclerosis

In Multiple Sclerosis (MS) prevalence studies of community and clinical samples, indicate that 45-60% of patients are cognitively impaired. These cognitive dysfunctions have been traditionally described as heterogeneous, but more recent studies suggest that there is a specific pattern of MS-related cognitive dysfunctions. With the advent of disease-modifying medications for MS and emphasis on early intervention and treatment, detection of cognitive impairment at its earliest stage becomes particularly important. In this review the authors address: the cognitive domains most commonly impaired in MS (memory, attention, executive functions, speed of information processing, and visual-spatial abilities); the pathophysiological mechanism implied in MS cognitive dysfunction and correlated brain MRI features; the importance of neuropsychological assessment of MS patients in different stages of the disease and the influence of its course on cognitive performance; the most used tests and batteries for neuropsychological assessment; therapeutic strategies to improve cognitive abilities.

Recommendations for a Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS)

Background: Cognitive impairment in MS impacts negatively on many patients at all disease stages and in all subtypes. Full clinical cognitive assessment is expensive, requiring expert staff and special equipment. Test versions and normative data are not available for all languages and cultures.

Objective: To recommend a brief cognitive assessment for multiple sclerosis (MS) that is optimized for small centers, with one or few staff members, who may not have neuropsychological training and constructed to maximize international use.

Methods: An expert committee of twelve members representing the main cultural groups that have so far contributed considerable data about MS cognitive dysfunction was convened. Following exhaustive literature review, peer-reviewed articles were selected to cover a broad spectrum of cultures and scales that targeted cognitive domains vulnerable to MS. Each was rated by two committee members and candidates scales were rated on psychometric qualities (reliability, validity, and sensitivity), international application, ease of administration, feasibility in the specified context, and acceptability to patients.

Results: The committee recommended the Symbol Digit Modalities Test, if only 5 minutes was available, with the addition of the California Verbal Learning Test – Second Edition and the Brief Visuospatial Memory Test – Revised learning trials if a further 10 minutes could be allocated for testing.

Conclusions: A brief cognitive assessment for MS has been recommended. A validation protocol has been prepared for language groups and validation studies have commenced.

Biological outcome measurements for behavioral interventions in multiple sclerosis

Behavioral interventions including exercise, stress management, patient education, psychotherapy and multidisciplinary neurorehabilitation in general are receiving increasing recognition in multiple sclerosis (MS) clinical practice and research. Most scientific evaluations of these approaches have focused on psychosocial outcome measures such as quality of life, fatigue or depression. However, it is becoming increasingly clear that neuropsychiatric symptoms of MS are at least partially mediated by biological processes such as inflammation, neuroendocrine dysfunction or regional brain damage. Thus, successful treatment of these symptoms with behavioral approaches could potentially also affect the underlying biology. Rigidly designed scientific studies are needed to explore the potential of such interventions to affect MS pathology and biological pathways linked to psychological and neuropsychiatric symptoms of MS. Such studies need to carefully select outcome measures on the behavioral level that are likely to be influenced by the specific intervention strategy and should include biomarkers with evidence for an association with the outcome parameter in question. In this overview, we illustrate how biological and psychological outcome parameters can be combined to evaluate behavioral interventions. We focus on two areas of interest as potential targets for behavioral interventions: depression and fatigue.

The effects of rivastigmine on processing speed and brain activation in patients with multiple sclerosis and subjective cognitive fatigue

Background: Cognitive decline and fatigue are typical in multiple sclerosis (MS). However, there is no official medication for either of these symptoms.

Objective: The purpose of this study was to estimate the effects of a single dose of rivastigmine on processing speed and associated brain activity in patients with MS and subjective cognitive fatigue.

Methods: Fifteen patients with MS and subjective cognitive fatigue and 13 healthy controls (HCs) matched for age, gender and education performed a neuropsychological assessment and functional (f)MRI. A modified version of the Paced Visual Serial Addition Test (mPVSAT) was used as the behavioural task during fMRIs. After the first scanning session, both groups were randomly divided into two subgroups receiving either rivastigmine or placebo. A single dose of rivastigmine or placebo was administrated double-blindly and 2.5 hours later the scanning was repeated.

Results: At baseline, the patients with MS showed slower processing speed in mPVSAT compared with the HCs. They also demonstrated stronger bilateral frontal activation after sustained cognitive effort than the HCs. Performance improvement and a further activation increase in the left anterior frontal cortex and additional activation in the right cerebellum were observed in patients who received rivastigmine but not in patients on placebo, or in HCs with placebo or rivastigmine.

Conclusion: These preliminary findings suggest that rivastigmine may improve cognitive processing speed by enhancing compensatory brain activation in patients with MS.

Cognition in multiple sclerosis

PURPOSE OF REVIEW

A broad overview of cognition in multiple sclerosis (MS) is provided, taking account of its impact on the lives of patients, how cognitive impairment relates to disease and magnetic resonance variables, which cognitive domains are most vulnerable, the influence of depression and fatigue and what treatment options are available.

RECENT FINDINGS

The current focus is on cognitive reserve, which seems to offer some protection from the cognitive impact of MS. There is also considerable momentum with new MRI techniques and growing interest in PET studies.

SUMMARY

Cognition in MS is a priority for patients. Although understanding of the natural history of MS cognitive deficits is reasonably well understood, treatment options require further work before precise recommendations can be made on an individual basis.

Therapeutics for multiple sclerosis symptoms

Symptoms management in multiple sclerosis is an integral part of its care. Accurate assessment and addressing the different symptoms provides increased quality of life among patients with multiple sclerosis. Multiple sclerosis symptoms may be identified as primary, secondary, or tertiary symptoms. Primary symptoms, such as weakness, sensory loss, and ataxia, are directly related to demyelination and axonal loss. Secondary symptoms, such as urinary tract infections as a result of urinary retention, are a result of the primary symptoms. Tertiary symptoms, such as reactive depression or social isolation, are a result of the social and psychological consequences of the disease. Common multiple sclerosis symptoms include fatigue and weakness; decreased balance, spasticity and gait problems; depression and cognitive issues; bladder, bowel, and sexual deficits; visual and sensory loss; and neuropathic pain. Less-common symptoms include dysarthria and dysphagia, vertigo, and tremors. Rare symptoms in multiple sclerosis include seizures, hearing loss, and paralysis. Symptom management includes nonpharmacological methods, such as rehabilitation and psychosocial support, and pharmacological methods, ie, medications and surgical procedures. The keys to symptom management are awareness, knowledge, and coordination of care. Symptoms have to be recognized and management needs to be individualized. Multiple sclerosis therapeutics include nonpharmacological strategies that consist of lifestyle modifications, rehabilitation, social support, counseling, and pharmacological agents or surgical procedures. The goal is vigilant management to improve quality of life and promote realistic expectations and hope.

Multicenter randomized clinical trial of donepezil for memory impairment in multiple sclerosis

OBJECTIVES

The goal of this study was to determine if memory would be improved by donepezil as compared to placebo in a multicenter, double-blind, randomized clinical trial (RCT).

METHODS

Donepezil 10 mg daily was compared to placebo to treat memory impairment. Eligibility criteria included the following: age 18-59 years, clinically definite multiple sclerosis (MS), and performance ≤ ½ SD below published norms on the Rey Auditory Verbal Learning Test (RAVLT). Neuropsychological assessments were performed at baseline and 24 weeks. Primary outcomes were change on the Selective Reminding Test (SRT) of verbal memory and the participant's impression of memory change. Secondary outcomes included changes on other neuropsychological tests and the evaluating clinician's impression of memory change.

RESULTS

A total of 120 participants were enrolled and randomized to either donepezil or placebo. No significant treatment effects were found between groups on either primary outcome of memory or any secondary cognitive outcomes. A trend was noted for the clinician's impression of memory change in favor of donepezil (37.7%) vs placebo (23.7%) (p = 0.097). No serious or unanticipated adverse events attributed to study medication developed.

CONCLUSIONS

Donepezil did not improve memory as compared to placebo on either of the primary outcomes in this study.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence which does not support the hypothesis that 10 mg of donepezil daily for 24 weeks is superior to placebo in improving cognition as measured by the SRT in people with MS whose baseline RAVLT score was 0.5 SD or more below average.

Cerebral acetylcholinesterase activity is not decreased in MS patients with cognitive impairment

BACKGROUND

Neuropsychological studies have extensively described the presence of cognitive dysfunction in MS patients. One possible pharmacological treatment of the impairment could be based on acetylcholinesterase inhibitors (AChEIs), which have shown efficacy in alleviating cognitive impairment in many other disorders. The findings on the efficacy of AChEI medication in MS associated cognitive symptoms are preliminary and no studies concerning cerebral acetylcholinesterase (AChE) activity in these patients have been published.

OBJECTIVE

The objective of the study was to examine cerebral AChE activity in cognitively deteriorated MS patients. Cerebral AChE activity of 10 MS patients with secondary progressive disease and marked cognitive impairment, and 10 healthy controls, was studied with positron emission tomography using tracer (11)C-MP4A.

METHODS

The cognitive profile of the patients was assessed with CERAD (Consortium to Establish a Registry for Alzheimer's Disease).

RESULTS

No differences in cortical AChE activity between MS patients and controls were seen.

CONCLUSIONS

In the patient group regional AChE activities had inverse correlations with Word learning and MMSE (Mini-Mental State Examination) scores. In the group of cognitively deteriorated MS patients no change in cerebral AChE activity, compared with controls, was observed, but within the patient group more pronounced cognitive symptoms were associated with higher cerebral AChE activity.

The effect of natalizumab on cognitive function in patients with relapsing-remitting multiple sclerosis: preliminary results of a 1-year follow-up study

The objective of the study was to assess the natalizumab effect on the course of cognitive impairment in patients with relapsing-remitting multiple sclerosis (MS). Patients with active relapsing-remitting MS (n = 17) were treated with natalizumab for 1 year. The quasi control group included patients (n = 7) with clinically stable MS. Assessment of disease course [expanded disability status scale (EDSS); number of relapses] and neuropsychological impairment [Wisconsin card sorting test (WCST); controlled oral word associations; verbal/non-verbal memory tests; paced auditory serial addition test] was conducted at baseline and after 1 year. Natalizumab-treated patients experienced significantly fewer relapses compared with the previous year (P < 0.05). At 1-year follow-up, EDSS score was unchanged and neuropsychological assessments of memory/executive functions showed a significant improvement in natalizumab-treated patients (all P < 0.05). No changes were observed in the quasi control group. This preliminary study suggests that natalizumab could be effective in ameliorating cognitive functions in patients with active relapsing-remitting MS, over 1-year follow-up.

Cognitive impairment in multiple sclerosis

Multiple sclerosis (MS) is a progressive disease of the CNS that is characterised by widespread lesions in the brain and spinal cord. MS results in motor, cognitive, and neuropsychiatric symptoms, all of which can occur independently of one another. The common cognitive symptoms include deficits in complex attention, efficiency of information processing, executive functioning, processing speed, and long-term memory. These deficits detrimentally affect many aspects of daily life, such as the ability to run a household, participate fully in society, and maintain employment--factors that can all affect the overall quality of life of the patient. The increased use of neuroimaging techniques in patients with MS has advanced our understanding of structural and functional changes in the brain that are characteristic of this disease, although much remains to be learned. Moreover, examination of efforts to treat the cognitive deficits in MS is still in the early stages.

Cognitive impairment in multiple sclerosis

BACKGROUND

Cognitive impairment is increasingly being recognized as a common and disabling symptom of multiple sclerosis (MS) that contributes to poor quality of life in affected patients. Despite the high prevalence of cognitive impairment in MS, cognitive function is not assessed routinely in clinical practice or in clinical trials. The perception that cognitive assessments are costly, time-consuming, complicated, and difficult to administer and interpret has contributed, at least in part, to the failure to incorporate cognitive testing into standard clinical evaluation of patients with MS. Detailed studies of cognitive impairment in MS are rare and guidelines for the assessment of cognitive function in MS are lacking.

TREATMENT

How to manage cognitive decline in MS also requires further study. Licensed disease-modifying drug (DMD) treatments for MS reduce brain lesion development, and associations between brain lesions and cognitive performance have been reported, providing a rationale for DMD treatment of MS-associated cognitive impairment. There is some evidence for cognitive benefits of DMDs, but as few pivotal DMD trials included cognitive assessments, the effects of these agents on cognition are not fully understood and more studies are needed.

CONCLUSIONS

It is only through further studies that it will be possible to identify patients with, or at risk of, cognitive impairment and to provide appropriate therapy to limit the effects of this potentially devastating symptom.