Longitudinal consistency of the relationship between depression symptoms and cognitive functioning in multiple sclerosis

Sleep and cognitive outcomes in multiple sclerosis; a systematic review

BACKGROUND

Multiple sclerosis (MS) is a disabling disease of the central nervous system. People living with MS often have co-existing sleep disorders and cognitive dysfunction. The objective of this study was to scrutinize the relationship between cognitive outcomes and sleep conditions in MS.

METHODS

This study followed the Joanna Briggs Institute's (JBI) and PRISMA guidelines. PubMed, Scopus, Embase, and Web of Science databases were searched and original studies delineating the relationship between sleep status and cognitive findings in MS patients‌ were included. The risk of bias was assessed using the JBI critical appraisal tools.

RESULTS

In the final review, out of 1635 screened records, 35 studies with 5321 participants were included. Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and polysomnography were the most common assessment tools for evaluation of sleep condition, and cognitive evaluations were conducted using the tests including Paced Auditory Serial Addition Test (PASAT), California Verbal Learning Test (CVLT), Symbol Digit Modalities Test (SDMT) and Brief Visuospatial Memory Test (BVMT). Assessing the quality of studies showed no significant bias in most of the included articles. A link between sleep condition and cognitive abilities was suggested in the literature, especially with objective measurement of sleep condition; however, current evidence did not support a substantial association between self-reported sleep quality and processing speed and working memory in patients with MS.

DISCUSSION

Evidence proposes sleep is an independent factor associated with cognitive outcomes in MS. Given the limitations of the evidence such as the lack of well-designed prospective studies, these findings need to be interpreted with caution.

The relationship between depression and cognitive performance in multiple sclerosis: A meta-analysis

Objective: Studies on the relationship between depression and cognition on patients with multiple sclerosis (MS) are inconsistent and it is not clear whether higher depression levels are associated with impairment of specific cognitive domains or processes. This meta-analytic study aimed at evaluating the possible association between depressive symptomatology and performance on cognitive tests assessing several cognitive domains (global cognition, attention, processing speed, verbal, spatial and working memory, verbal fluency, inhibitory control, set-shifting) in individuals living with MS. Method: The literature search on three electronic databases yielded 5402 studies (4333 after the duplicates removal); after the evaluation of titles, abstracts full-text articles, 37 studies were included in the meta-analytic study. A random-effect model meta-analysis was performed and mean weighted effect sizes (ESs) were calculated using Hedges' g. Results: Small ESs were found for the relationship between depression and verbal memory (g = 0.25, p < 0.001), spatial memory (g = 0.23, p < 0.001), verbal fluency (g = 0.26, p < 0.001), and inhibitory control (g = 0.32, p = 0.003). Medium ESs were found for the relationship between depression and global cognition (g = 0.46, p < 0.001), attention (g = 0.43, p < 0.001), processing speed (g = 0.47, p < 0.001) and working memory (g = 0.38, p = 0.037). The relationship between set-shifting abilities and depression was not significant (g = 0.39, p = 0.095). Conclusions: Results suggest that patients with MS and higher levels of depressive symptomatology may also show more difficulties in several aspects of cognition, especially those needed to retain, respond, and process information in one's environment, and to those needed be adequately stimulated in processing relevant information.

The prevalence of major depression and generalized anxiety disorder in patients with multiple sclerosis in Saudi Arabia: a cross-sectional multicentered study

Background

Multiple sclerosis (MS) is an autoimmune disease characterized by chronic, progressive neurodegeneration of the central nervous system (CNS), and it is the most common inflammatory neurological disease affecting young adults. Given the chronic, progressive nature of the disease, psychiatric disorders are more prevalent among these patients, as reported in the literature; however, data in Saudi Arabia are limited. This study aimed to estimate the prevalence of major depression and generalized anxiety disorder in patients with MS and their association with different patient demographics.

Methods

This was a cross-sectional, multicentered study that included adult patients with MS from 30 June 2021 to 30 June 2022. Participants were interviewed in person and asked to complete a survey that included general demographics, the Patient Health Questionnaire-9 (PHQ-9), and the Generalized Anxiety Disorder-7 (GAD-7) questionnaire. Other variables related to the patients' conditions, such as MS type and Expanded Disability Status Scale (EDSS) score, were collected from the patient's electronic records. Descriptive statistics were performed, and associations were made using the chi-square, Fisher's exact, and analysis of variance tests, as appropriate.

Results

A total of 192 participants were included in this study. Based on a cutoff score of >10 on the GAD-7 and PHQ-9 scales, the prevalence of generalized anxiety disorder was 26.1% (50), with the majority of participants having minimal anxiety (40%); meanwhile, the prevalence of major depression was 42.7% (n = 82), and most of them had mild depression (30%). Female participants scored significantly higher compared to men on the GAD-7 scale (p = 0.0376), but not on the PHQ-9 scale (p = 0.1134). In addition, no statistically significant association was detected between functional disability (EDSS score) and prevalence of anxiety and depression.

Conclusion

This study demonstrated a high prevalence of generalized anxiety disorder and major depression among patients with MS compared with that in the general population, with women being more affected. As these comorbid disorders could negatively affect the disease course, screening is of paramount significance.

Effects of Vascular Comorbidity on Cognition in Multiple Sclerosis Are Partially Mediated by Changes in Brain Structure

Objective

Vascular comorbidities are associated with reduced cognitive performance and with changes in brain structure in people with multiple sclerosis (MS). Understanding causal pathways is necessary to support the design of interventions to mitigate the impacts of comorbidities, and to monitor their effectiveness. We assessed the inter-relationships among vascular comorbidity, cognition and brain structure in people with MS.

Methods

Adults with neurologist-confirmed MS reported comorbidities, and underwent assessment of their blood pressure, HbA1c, and cognitive functioning (i.e., Symbol Digit Modalities Test, California Verbal Learning Test, Brief Visuospatial Memory Test-Revised, and verbal fluency). Test scores were converted to age-, sex-, and education-adjusted z-scores. Whole brain magnetic resonance imaging (MRI) was completed, from which measures of thalamic and hippocampal volumes, and mean diffusivity of gray matter and normal-appearing white matter were converted to age and sex-adjusted z-scores. Canonical correlation analysis was used to identify linear combinations of cognitive measures (cognitive variate) and MRI measures (MRI variate) that accounted for the most correlation between the cognitive and MRI measures. Regression analyses were used to test whether MRI measures mediated the relationships between the number of vascular comorbidities and cognition measures.

Results

Of 105 participants, most were women (84.8%) with a mean (SD) age of 51.8 (12.8) years and age of symptom onset of 29.4 (10.5) years. Vascular comorbidity was common, with 35.2% of participants reporting one, 15.2% reporting two, and 8.6% reporting three or more. Canonical correlation analysis of the cognitive and MRI variables identified one pair of variates (Pillai's trace = 0.45, p = 0.0035). The biggest contributors to the cognitive variate were the SDMT and CVLT-II, and to the MRI variate were gray matter MD and thalamic volume. The correlation between cognitive and MRI variates was 0.50; these variates were used in regression analyses. On regression analysis, vascular comorbidity was associated with the MRI variate, and with the cognitive variate. After adjusting for the MRI variate, vascular comorbidity was not associated with the cognitive variate.

Conclusion

Vascular comorbidity is associated with lower cognitive function in people with MS and this association is partially mediated via changes in brain macrostructure and microstructure.

aHSCT is superior to alemtuzumab in maintaining NEDA and improving cognition in multiple sclerosis

Objective

Autologous hematopoietic stem cell transplantation (aHSCT) is increasingly recognized as a potential therapy for patients with highly active multiple sclerosis (MS). This study aims to assess outcome differences in disease activity in MS patients treated either with aHSCT or alemtuzumab.

Methods

We conducted a monocentric registry‐based cohort study by recording the clinical course (EDSS and relapses), MRI parameters (new T2 lesions), and neuropsychological assessment in all 19 MS patients receiving aHSCT, and all 21 patients receiving alemtuzumab between 2007 and 2018. We used survival analyses of no evidence of disease activity (NEDA) as the primary objective which was defined by no EDSS progression, no relapse, and no new T2 lesion on MRI. Secondary objectives were EDSS improvement and neurocognitive performance.

Results

Both treatment groups were similar in respect of age, gender, disability, and neurocognitive performance except for significantly longer disease duration in the alemtuzumab group. Mean follow‐up was 58.8 [range 29–140] months in the aHSCT group compared to 27.6 [range 11–52] months in the alemtuzumab‐treated group. We observed significantly more patients maintaining NEDA in the aHSCT group (p = 0.048) compared to the alemtuzumab‐treated patients. Furthermore, 37% of the aHSCT patients showed an improvement of EDSS compared to none in the alemtuzumab‐treated group (p = 0.033). It is of note that cognitive function was significantly improved in the aHSCT‐treated patients.

Interpretation

aHSCT suppresses inflammatory activity more effectively than alemtuzumab and might enable improvement of overall disability and cognition in MS.

Short-term data on disease activity, cognition, mood, stigma and employment outcomes in a cohort of patients with primary progressive multiple sclerosis (UPPMS study)

BACKGROUND

Primary progressive multiple sclerosis (PPMS) has long been defined by progressive disability accrual in the absence of initial relapses. However, its underlying neurodegenerative process seems to be accompanied by central nervous system inflammation. A new classification defined multiple sclerosis courses according to clinical/radiological activity and progression. We provide further insight into PPMS activity according to this classification and other daily living aspects.

METHODS

This was a multicentre, prospective, cohort study including 55 adult patients with PPMS according to 2010 McDonald criteria, within ten years from neurologic symptom onset and not receiving disease-modifying therapies during the past six months, who were followed up for 12 months. The primary study endpoint was the percentage of patients with active disease based on clinical relapses and/or magnetic resonance activity. Disability progression, cognitive function, physical/psychological impact, depression symptoms, stigma and employment were secondary endpoints.

RESULTS

Eleven (25.6%) patients exhibited multiple sclerosis activity throughout the 12-month study follow-up. Fourteen showed non-active multiple sclerosis without progression, 11 non-active multiple sclerosis with progression, 6 active multiple sclerosis without progression and 4 active multiple sclerosis with progression; one patient with disease activity was not assessable for progression. Cognitive function scores remained unchanged or increased, disease physical impact was maintained and disease psychological impact significantly decreased. The proportion of patients with depression symptoms or stigma remained without significant changes as well as employment outcomes.

CONCLUSION

This study shows that one-fourth of PPMS patients may exhibit disease activity over one year, with disability progression in approximately one-third but without worsening of cognitive function, disease impact, depression, stigma or employment outcomes.

Anxiety and depression affect performance on the symbol digit modalities test over time in MS and other immune disorders

Background:

Longitudinal studies assessing depression and anxiety effects on cognition in multiple sclerosis (MS) are limited.

Objective:

We tested whether within-person fluctuations in symptoms of depression or anxiety over time affect cognition in persons with MS, inflammatory bowel disease (IBD), rheumatoid arthritis (RA), and a lifetime history of depression/anxiety disorders (DEP/ANX) but without an immune-mediated inflammatory diseases (IMID).

Methods:

We followed participants (MS: 255, IBD: 247, RA: 154, and DEP/ANX: 306) for 3 years. Annually, they completed the hospital anxiety and depression scale (HADS) and cognitive tests including the symbol digit modalities test (SDMT). We evaluated associations of elevated symptoms (scores ⩾ 11) of anxiety (HADS-A) and depression (HADS-D) with SDMT z-scores using multivariable linear models—estimating between-person and within-person effects.

Results:

Participants with MS performed worse on the SDMT than participants in the DEP/ANX cohort (β = −0.68; 95% CI: −0.88, −0.48). Participants with elevated HADS-A scores performed worse on the SDMT than those without elevated scores (β = −0.43; 95% CI: −0.65, −0.21), particularly those with RA. Time-varying within-person elevations in depressive symptoms were associated with worse SDMT performance (β = −0.12; 95% CI: −0.21, −0.021).

Conclusions:

Across persons, elevated symptoms of anxiety adversely affected information processing. Elevated symptoms of depression within-persons over time were associated with declines in information processing speed.

The relation between memory and decision-making in multiple sclerosis patients

BACKGROUND

Impairments in long-term and working memory are widespread in Multiple Sclerosis (MS), setting on in early disease stages. These memory impairments may limit patients' ability to take informed and competent medical decisions, too. In healthy populations, memory abilities predict decision quality across a wide range of tasks. These studies suggest that higher working memory capacity supports decisions in cognitively taxing tasks, whereas better semantic memory facilitates decisions in tasks requiring knowledge retrieval. In individuals with MS, previous studies have linked less accurate decisions to memory deficits and reduced executive functioning, too. However, these studies focussed on decisions under risk and did not broadly assess decision making skills. We aimed to fill this gap in a cross-sectional study.

METHODS

Hundred thirty-seven participants with MS were recruited during their stay in an MS specialized rehabilitation centre. In a first test session, participants completed a standardized test battery for working memory and semantic memory, the inventory for memory diagnostics. In a second test session, participants filled out the Adult Decision Making Competence battery (A-DMC). This version of the A-DMC measured decision making competence on five subscales: Resistance to Framing Effects, Under/Overconfidence, Applying Decision Rules, Consistency in Risk Perception, and Resistance to Sunk Cost Effects. In addition, participants were screened for depression and cognitive fatigue.

RESULTS

Working memory was impaired in most participants, whereas semantic memory was not impaired. To understand which memory abilities underlie distinct components of decision making in people with MS, we used structural equation modelling. Replicating previous findings in a healthy sample, working memory capacity was associated with the ability to recall semantic knowledge. Participants with lower working memory capacity were less resistant to framing effects and adhered to decision rules less. In contrast, participants with worse semantic memory assessed their own knowledge less accurately, perceived risks less consistently, and made more errors in applying decision rules. Cognitive fatigue and depression unlikely explain these relationships.

CONCLUSIONS

Taken together, our study suggests that the memory problems, frequently reported in MS patients, may reach out to higher-order cognitive functions, such as decision making skills. Supporting shared decision-making and patient autonomy within MS thus requires to take memory impairments into account and to match the information provided to the patient's memory abilities.

Cognitive Dysfunctions and Assessments in Multiple Sclerosis

Cognitive impairment has been reported at all phases and all subtypes of multiple sclerosis. It remains a major cause of neurological disability in young and middle-aged adults suffering from the disease. The severity and type of cognitive impairment varies considerably among individuals and can be observed both in early and in later stages. The areas which have commonly shown more deficits are: information processing speed, complex attention, memory, and executive function. Even though an alteration in both the white matter and in the gray matter has been found in patients with multiple sclerosis and cognitive impairment, the underlying process still remains unknown. Standardized neurological examinations fail to detect emerging cognitive deficits and self-reported cognitive complaints by the patients can be confounded by other subjective symptoms. This review is a comprehensive and short update of the literature on cognitive dysfunctions, the possible confounders and the impact of quality of life in patients with multiple sclerosis.

Apathy as a herald of cognitive changes in multiple sclerosis: A 2-year follow-up study

Background:

Behavioral symptoms, such as apathy and depression, are common in multiple sclerosis (MS) but their relationship with cognitive and clinical characteristics often remains underinvestigated and not monitored over time.

Objective:

The aim of this study was to assess the evolution of cognitive profile of patients affected by MS in relation to apathy and depression using a 2-year follow-up study.

Methods:

Two years after the first assessment, 100 of 125 MS patients were re-evaluated on a comprehensive neuropsychological battery, and on specific scales for assessment of apathy (Apathy Evaluation Scale—Self-reported) and depression (Hamilton Depression Rating Scale).

Results:

After 2 years (T1), we found a relatively consistent prevalence of apathy (about 40%) and a reduction in prevalence of depression (from 44% to 30%). Higher level of apathy at baseline predicted the progressive cognitive changes at follow-up; and patients with apathy without depression (“pure” apathy) than patients without apathy had poorer performance on the interference task of the Stroop test assessing inhibitory control.

Conclusion:

The present results suggested that apathy in MS was associated with more severe executive dysfunctions (in particular cognitive control). Apathy rather than depression predicted cognitive impairment in MS over time.

Does including the full CVLT-II and BVMT-R improve BICAMS? Evidence from a Belgian (Dutch) validation study

BACKGROUND

The Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) is a fast, easy-to-administer and already widely validated neuropsychological battery for cognition in multiple sclerosis.

OBJECTIVE

The goals of our study were to validate the BICAMS in a Belgian Dutch-speaking population and to investigate to what extent including extensive versions of two of the three BICAMS subtests improved its psychometric qualities.

METHODS

Ninety-seven persons with MS and ninety-seven healthy controls were included and group-matched on age, education level and gender. All participants performed the BICAMS with an extensive version of the CVLT-II and BVMT-R.

RESULTS

The SDMT and BVMT-R were able to dissociate between the MS and healthy control group, while the CVLT-II was not. Distributions of CVLT-II scores suggest learning effects in the MS group, indicating the need for alternative word lists or the construction of an adapted version fitted for repeated administration. Including the full CVLT-II and BVMT-R did not markedly improve the psychometric qualities of the BICAMS.

CONCLUSION

This study validates the BICAMS in a Belgian Dutch-speaking population and facilitates the use of it in clinical practice, while providing evidence that including full versions of the CVLT-II and BVMT-R does not increase its psychometric qualities markedly.

Neuropsychological Assessment in Multiple Sclerosis

Abstract. Neuropsychological deficits in multiple sclerosis (MS) are common. Over the past decades, many different procedures have been employed in diagnosing these deficits. Even though certain aspects of cognitive performance such as information processing speed and working memory may be affected more frequently than other cognitive functions, no specific deficit profile has been established in MS. This article provides an overview of the neuropsychological diagnostic procedures in MS and allows the reader to reach an informed decision on the applicability of specific procedures and the availability of study data in the context of MS. Additionally, it makes recommendations on the compilation of both screening procedures and extensive test batteries.

Long Term Clinical Prognostic Factors in Relapsing-Remitting Multiple Sclerosis: Insights from a 10-Year Observational Study

Background

Multiple sclerosis (MS) has a highly heterogenic course making prediction of long term outcome very difficult.

Objective

The objective was to evaluate current and identify additional clinical factors that are linked to long term outcome of relapsing-remitting MS assessed by disability status 10 years after disease onset.

Methods

This observational study included 793 patients with relapsing-remitting MS. Clinical factors hypothesized to influence long term outcome measured by EDSS scores 10 years after disease onset were analysed by Kaplan-Meier-estimates. Multinomial logistic regression models regarding mild (EDSS ≤2.5), moderate (EDSS 3.0–5.5) or severe (EDSS ≥6.0) disability were calculated to correct for confounders.

Results

Secondary progression was the strongest predictor of severe disability (Hazard ratio [HR] 503.8, 95% confidence interval [CI] 160.0–1580.1); p<0.001). Complete remission of neurological symptoms at onset reduced the risk of moderate disability (HR 0.42; CI 0.23–0.77; p = 0.005), while depression (HR 3.59; CI 1.14–11.24; p = 0.028) and cognitive dysfunction (HR 4.64; CI 1.11–19.50; p = 0.036) 10 years after disease onset were associated with severe disability. Oligoclonal bands and pregnancy were not correlated with disability.

Conclusion

We were able to identify clinically apparent chronic depression and cognitive dysfunction to be associated with adverse long term outcome in MS and to confirm that pregnancy has no negative impact. Additionally, we emphasize the positive predictive value of complete remission of initial symptoms.

The Rao's Brief Repeatable Battery in the study of cognition in different multiple sclerosis phenotypes: application of normative data in a Serbian population

Cognitive impairment is prevalent in multiple sclerosis (MS) occurring in 43-72 % of patients with all MS phenotypes. The aim of our study was to assess cognitive performance in different MS subtypes in Serbian population. Rao's Brief Repeatable Battery of neuropsychological tests (BRB-N) was administered to 168 MS patients [37 patients with clinically isolated syndrome (CIS) suggestive of MS, 65 with relapsing-remitting MS (RRMS), 31 with secondary progressive MS (SPMS) and 35 patients with primary progressive MS (PPMS)]. The percentage of cognitively impaired patients in our total MS cohort was 58.9 %. Prevalence of cognitive dysfunction was 40.5 % in CIS group, 36.9 % in RRMS, 96.8 % in SPMS, and 85.7 % in PPMS group. Patients in CIS and RRMS groups performed consistently better all tests of the Rao's battery than patients in SPMS and PPMS cohort. CIS and RRMS groups performed consistently better in all tests of the Rao's battery than SPMS and PPMS cohort. Additionally, difference in the performance of any of the BRB-N tests was not found between CIS and RRMS. However, there was a significant difference between SPMS and PPMS patients in the performance on five tests of Rao's battery. Statistical significance (p < 0.05) in favor of PPMS patients was demonstrated for the following tasks: SRT_lts, SRT_cltr, SDMT, SRT_D, SPART_D. Our study demonstrates that cognitive impairment is frequent in all MS phenotypes. Furthermore, we have found that cognitive deficit is most severe and most frequent in SPMS patients, followed by PPMS subjects and then CIS and RRMS patients.

Recommendations for observational studies of comorbidity in multiple sclerosis

OBJECTIVE

To reach consensus about the most relevant comorbidities to study in multiple sclerosis (MS) with respect to incidence, prevalence, and effect on outcomes; review datasets that may support studies of comorbidity in MS; and identify MS outcomes that should be prioritized in such studies.

METHODS

We held an international workshop to meet these objectives, informed by a systematic review of the incidence and prevalence of comorbidity in MS, and an international survey regarding research priorities for comorbidity.

RESULTS

We recommend establishing age- and sex-specific incidence and prevalence estimates for 5 comorbidities (depression, anxiety, hypertension, hyperlipidemia, and diabetes); evaluating the effect of 7 comorbidities (depression, anxiety, hypertension, diabetes, hyperlipidemia, chronic lung disease, and autoimmune diseases) on disability, quality of life, brain atrophy and other imaging parameters, health care utilization, employment, and mortality, including age, sex, race/ethnicity, socioeconomic status, and disease duration as potential confounders; harmonizing study designs across jurisdictions; and conducting such studies worldwide. Ultimately, clinical trials of treating comorbidity in MS are needed.

CONCLUSION

Our recommendations will help address knowledge gaps regarding the incidence, prevalence, and effect of comorbidity on outcomes in MS.

Impact of depression, fatigue, and global measure of cortical volume on cognitive impairment in multiple sclerosis

Objective. To investigate the influence of demographic and clinical variables, such as depression, fatigue, and quantitative MRI marker on cognitive performances in a sample of patients affected by multiple sclerosis (MS). Methods. 60 MS patients (52 relapsing remitting and 8 primary progressive) underwent neuropsychological assessments using Rao's Brief Repeatable Battery of Neuropsychological Tests (BRB-N), the Beck Depression Inventory-second edition (BDI-II), and the Fatigue Severity Scale (FSS). We performed magnetic resonance imaging to all subjects using a 3 T scanner and obtained tissue-specific volumes (normalized brain volume and cortical brain volume). We used Student's t-test to compare depressed and nondepressed MS patients. Finally, we performed a multivariate regression analysis in order to assess possible predictors of patients' cognitive outcome among demographic and clinical variables. Results. 27.12% of the sample (16/59) was cognitively impaired, especially in tasks requiring attention and information processing speed. From between group comparison, we find that depressed patients had worse performances on BRB-N score, greater disability and disease duration, and brain volume decrease. According to multiple regression analysis, the BDI-II score was a significant predictor for most of the neuropsychological tests. Conclusions. Our findings suggest that the presence of depressive symptoms is an important determinant of cognitive performance in MS patients.

Perceived cognitive decline in multiple sclerosis impacts quality of life independently of depression

Background/Aim. The aim of this study is to examine the effects of perceived cognitive dysfunction and of depression, on self-reported QoL, in a Greek population sample of MS patients. Methods. One hundred outpatients diagnosed with MS completed the Short-Form-36 Health Survey (SF-36), as well as the Perceived Deficits Questionnaire (PDQ) and the Depression subscale of the Mental Health Inventory (MHI), as part of a clinical evaluation which included the Expanded Disability Status Scale (EDSS) estimation. Multiple linear regression was conducted to determine the best linear combination of age, gender, education, EDSS, depression, attention/concentration, retrospective memory, prospective memory, and planning/organization, for predicting QoL scores. Results. In the multivariate regression analysis models, EDSS (P < 0.05), depression (P < 0.001), perceived planning/organization (P < 0.05), and perceived retrospective memory dysfunction (P < 0.05) independently predict quality of life scores. Age, sex, education level, and perceived attention/concentration dysfunction, as well as perceived prospective memory dysfunction, do not independently predict quality of life scores. Conclusions. Perceived planning/organization impairment and perceived retrospective memory impairment in MS patients predict QoL independently of the severity of disease and the severity of depression and therefore should be considered in the assessment of patient health status as well as in the design of treatment interventions and rehabilitation.

Neuropsychiatric manifestations of multiple sclerosis

Multiple sclerosis is one of the most frequently observed neurological causes of progressive disability in early to middle adulthood. The disease is variable in its presentation and course, affects roughly 100 to 300 per 100,000 persons within the US alone and is slightly more common among females than males. Multiple sclerosis places substantial burdens on patients, families and caregivers. Its presentation includes disturbances in cognitive abilities and psychiatric functioning, as well as motor difficulties. This article reviews the current literature on the neuropsychiatric manifestations of multiple sclerosis. Cognitive domains discussed include general cognitive functioning, learning and memory ability, attention, processing speed, executive functioning, visual perceptual ability and language functioning. Attention is also given to alterations in neuropsychiatric functioning associated with disease progression and across various disease subtypes. In addition, reports are also reviewed regarding various psychiatric disturbances, affective changes, quality of life issues and fatigue and pain in individuals with multiple sclerosis. Finally, factors pertaining to pediatric populations in multiple sclerosis are addressed.

Cortical pathology and cognitive impairment in multiple sclerosis

Cognitive impairment constitutes a relevant clinical aspect of multiple sclerosis (MS). Depending on the disease phase and type, 40-65% of MS patients develop various degrees of cognitive dysfunction. Pathological and MRI studies have failed to demonstrate the existence of a strict relationship between cognitive impairment and subcortical white matter pathology. The correlation is also poor when MRI metrics of whole brain (white plus gray matter) atrophy are considered. Over the last decade, increasing observations have provided evidence of a primary role of cortical pathology - that is, inflammatory focal lesions (cortical lesions) and atrophy (cortical thickness) - in determining global and/or selective cognitive disability in MS. By applying a new semi-automated software (Freesurfer) to analyze the global and regional cortical thickness and the double inversion recovery sequence to identify cortical lesions, it has been observed that specific cognitive deficits, such as memory impairment, attention deficits and reduced mental processing speed, could be better explained by cortical structural abnormalities rather than subcortical white matter lesions. Therefore, MRI evaluation of cortical pathology should be included in the routine examination of MS patients, especially those with initial signs/symptoms of cognitive dysfunctions.

Cognitive function, depression, fatigue, and activities of daily living in patients with neuromyelitis optica after acute relapse

The status of fatigue, depression, and activities of daily living and their relationships with cognitive function in patients with neuromyelitis optica (NMO) after acute relapse has never been observed. This study investigated cognitive function, fatigue, depression, activities of daily living, and the relationships among them in NMO patients. Twenty-two NMO patients without visible lesions on conventional brain MRI after acute relapse, 22 depression patients, and 22 healthy comparison subjects received several scales to assess cognitive function, fatigue, and depression. Every NMO patient completed a survey of activities of daily living. Between-group comparisons and correlational analyses were applied to examine the differences and the relationships among them. We found that NMO patients had significantly impaired memory, decreased information processing speed, and damaged attention. Some impaired cognitive domains were significantly correlated with fatigue and depression, and activities of daily living were correlated with these impaired cognitive domains, fatigue, depression, and disability. These results confirm cognitive deficits in memory, information processing speed, and attention exist in NMO patients without visible brain lesions after acute relapse. Fatigue and depression may affect cognitive function and increase the negative impact of cognitive deficits on the activities of daily living in patients with NMO.

Relationship between global cognitive decline and depressive symptoms in multiple sclerosis

Cognitive impairment and depressed mood are common symptoms in multiple sclerosis (MS), which significantly impact patients' role functioning and quality of life. Cross-sectional studies indicate a modest association between cognitive impairment and depressive symptoms in MS. Longitudinal studies show inconsistent results but provide some data indicating a relationship between increasing global cognitive decline and increasing depressive symptoms over time. Establishing whether such a relationship exists represents an important first step in understanding the temporal nature of that relationship along with any treatment implications. The current study investigated this relationship by using the adjusted difference between a demographic estimate of premorbid intellectual functioning (Barona) and a performance measure of current intellectual functioning (Shipley Institute of Living) to capture long-term global cognitive decline in MS patients. Degree of global cognitive decline was then related to a self-report measure of mood, evaluative, and vegetative depression symptoms (Chicago Multiscale Depression Inventory). Global cognitive decline accounted for 5% of the variance in mood-evaluative symptoms but none of the variance in vegetative symptoms. When groups experiencing moderate, mild, and no global cognitive decline were compared on depression symptom subscales, MS patients experiencing moderate cognitive decline reported significantly higher mood and evaluative, but not vegetative, depressive symptoms than MS patients with stable cognitive functioning.

Relationship between depression, fatigue, subjective cognitive impairment, and objective neuropsychological functioning in patients with multiple sclerosis

OBJECTIVE

This study explored the influence of depression and fatigue on subjective cognitive complaints and objective neuropsychological impairment in patients with multiple sclerosis (MS).

METHODS

Data for this study were taken from a randomized controlled trial, comparing 16 weeks of telephone-administered cognitive-behavioral therapy and telephone-administered supportive emotion focused therapy for the treatment of depression. The sample includes 127 patients with MS. The following self-report measures were collected pre- and posttreatment: Perceived Deficits Questionnaire, Beck Depression Inventory-II, and Modified Fatigue Impact Scale. Measures of objective cognitive functioning and the Hamilton Rating Scale for Depression were administered over the telephone.

RESULTS

Our results showed that changes in depression and fatigue significantly predicted changes in subjective cognitive complaints from pre- to posttreatment, with patients perceiving fewer cognitive problems at posttreatment (beta = .36, p < .001 and beta = .61, p < .001, respectively). Changes in depression and fatigue were not significantly related to changes in objective neuropsychological performance. Improvements in depression and fatigue also predicted improved accuracy in perceiving cognitive abilities from pre- to posttreatment (OR = .77, p < .001 and OR = .90, p < .001, respectively).

CONCLUSIONS

The results of this study suggest that improvements in depression and fatigue through treatment do not influence objective neuropsychological performance in MS patients, but do relate to changes in subjective impairment. Furthermore, these changes improve patients' abilities to accurately perceive their cognitive functioning.

Examination of processing speed deficits in multiple sclerosis using functional magnetic resonance imaging

Although it is known that processing speed deficits are one of the primary cognitive impairments in multiple sclerosis (MS), the underlying neural mechanisms responsible for impaired processing speed remain undetermined. Using BOLD functional magnetic resonance imaging, the current study compared the brain activity of 16 individuals with MS to 17 healthy controls (HCs) during performance of a processing speed task, a modified version of the Symbol Digit Modalities Task. Although there were no differences in performance accuracy, the MS group was significantly slower than HCs. Although both groups showed similar activation involving the precentral gyrus and occipital cortex, the MS showed significantly less cerebral activity than HCs in bilateral frontal and parietal regions, similar to what has been reported in aging samples during speeded tasks. In the HC group, processing speed was mediated by frontal and parietal regions, as well as the cerebellum and thalamus. In the MS group, processing speed was mediated by insula, thalamus and anterior cingulate. It therefore appears that neural networks involved in processing speed differ between MS and HCs, and our findings are similar to what has been reported in aging, where damage to both white and gray matter is linked to processing speed impairments.

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.

Negative affect predicts subsequent cognitive change in multiple sclerosis

Baseline predictors of cognitive change were explored in a sample of persons with multiple sclerosis (MS). Potential predictors included demographic features, baseline clinical characteristics, and psychological state. Participants were 38 individuals diagnosed with either relapsing remitting or secondary progressive MS who did not meet criteria for a current major depressive episode. Subjects were tested at baseline and approximately 1 year in an ongoing longitudinal study of cognition in MS. Participants completed neuropsychological tests sensitive to impairment in MS. They also completed self-report measures of depression, anxiety, fatigue, apathy, and positive and negative affect. Baseline measures of negative affect (e.g., depressed mood, state anxiety, and negative affective state) consistently predicted cognitive change over the course of the study. Higher baseline levels of negative affect were associated with greater relative declines in cognitive performance. This longitudinal relation occurred in the absence of a cross-sectional relation between negative affect and overall cognition. High baseline negative affect particularly predicted a relative decline in episodic memory for newly learned verbal and visuospatial information. The negative affect measures were unique in their predictive value among all the baseline measures assessed. (JINS, 2009, 15, 53-61.).

Depression in multiple sclerosis: review and theoretical proposal

Because of its high prevalence and implications for quality of life and possibly even disease progression, depression has been intensively studied in multiple sclerosis (MS) over the past 25 years. Despite the publication of numerous excellent empirical research papers on this topic during that time, the publication of theoretical work that attempts to explain depression in a comprehensive way is scarce. In this study, we present a theoretical model that attempts to integrate existing work on depression in MS and provide testable hypotheses for future work. The model suggests that risk for depression begins with the onset of MS. MS results in disease-related changes such as increased lesion burden/brain atrophy and immunological anomalies that are associated with depression in MS, but explain only a relatively limited proportion of the variance. Common sequelae of MS including fatigue, physical disability, cognitive dysfunction, and pain, have all been shown to have an inconsistent or relatively weak relationship to depression in the literature. In the model, we propose that four variables--social support, coping, conceptions of the self and illness, and stress--may moderate the relationship between the above common MS sequelae with depression and help to explain inconsistencies in the literature.

Cognitive impairment in relapsing-remitting multiple sclerosis can be predicted by imaging performed several years earlier

Cognitive deficits in multiple sclerosis (MS) are common and correlate with contemporary MRI brain abnormalities, particularly atrophy, but the ability of imaging early in the disease to predict later cognitive impairment remains to be determined. Thirty relapsing-remitting MS patients recruited within three years of the onset of the disease, and in whom MRI had been performed at baseline and a year later, were assessed neuropsychologically five years later. Imaging parameters accounting for significant variance in cognitive performance were identified using multiple regressions, once confounding variables were controlled. Patients performed significantly worse than expected on tests of attention/speed of information processing and half of them had experienced some decline in IQ in relation to premorbid estimates. The rate of global brain atrophy in the first year of the study accounted for significant variance in the overall cognitive performance, and in memory and attention/speed of information processing. Poor performance on attention tests was associated with high T1-weighted lesion volume and reduced magnetization transfer ratio (MTR) in normal-appearing white matter (NAWM). These results suggest that neuroaxonal loss was identified early in the disease, and its rate of progression, predicted cognitive impairment later in the disease. Neuroaxonal loss is likely to affect commissural and association fibres that subserve the cognitive processes impaired in MS.

Coping and quality of life in one hundred and thirty five subjects with multiple sclerosis

INTRODUCTION

and objective The aim of this study was to compare coping strategies and quality of life (QoL) in multiple sclerosis (MS), as they relate to the course of the disease (relapsing-remitting (RR), secondary progressive (SP), primary progressive (PP)), while taking depression and anxiety into account.

METHODS

A total of 135 MS subjects were seen for a semi-structured interview in order to collect socio-demographic and clinical information, after which there was an assessment of their mental and cognitive states (Mini International Neuropsychiatric Interview (MINI), Montgomery and Asberg Depression Rating Scale (MADRS), Depressive Mood Scale (EHD), Hamilton Anxiety (HAMA), Frontal Assessment Battery (FAB)). All subjects then completed three self-report questionnaires; two about coping strategies (Ways of Coping Checklist (WCC), Coping with Health, Injuries and Problems Scale (CHIP)) and one about QoL (SEP59).

RESULTS

The mental health (depression and anxiety) and the psychological and social dimensions of QoL were relatively unaffected. However, after controlling for age and disability, the disease course had a strong effect on both mental health and QoL, with the poorest condition for SPMS and the best condition for PPMS. The SPMS patients tend to use emotional coping strategies extensively, while the PPMS patients use more instrumental strategies.

DISCUSSION

Our study clearly demonstrated that psychological and social well-being were substantially affected by the disease course. These results encourage us to develop interventions focused on coping strategies and which are better adapted to individual patients.

Multiple sclerosis and behavior

Multiple sclerosis (MS) is one of the most frequently seen neurological causes of progressive disability in early to middle adulthood. The disease is variable in its presentation and course, affects roughly 100-300 per 100,000 persons within the United States alone, and is slightly more common among females than males. MS places substantial burdens on patients, families, and caregivers. It negatively affects cognitive abilities and psychiatric functioning, and can add a notably deleterious effect on a patient's quality of life. This chapter reviews the recent literature on the behavioral manifestations of MS. Cognitive domains discussed include executive functioning, processing speed, attention, learning and memory, language functioning, and visual spatial processing. Some attention will also be paid to differential diagnosis and the cognitive effects of treatment. Psychiatric manifestations are also discussed, including symptoms of depression, bipolar disorder, euphoria, pathological laughter and crying, and psychosis, as well as maladaptive personality traits. Finally, the chapter concludes with a discussion of the effects of MS on quality of life including such areas as fatigue, sexual dysfunction, pain, employment, and cognitive functioning.