Decision-making impairment in patients with multiple sclerosis: a case-control study

A new framework for understanding stress and disease: the developmental model of stress as applied to multiple sclerosis

This paper proposes a new model of stress that integrates earlier models and adds insights from developmental psychology. Previous models describe the behavioral and physical effects of stress events, but have not explained the translation of experiences into stress itself. The Developmental Model of Stress shows how psychosocial developmental challenges in childhood create persistent negative beliefs and behaviors that increase threat perception and maladaptive stress responses. These developmental challenges produce early psychological and physiological predispositions for increased stress responses over time. Ongoing stress leads to dysregulation of physical stress-response systems (allostatic load), which is associated with multiple diseases. High allostatic load provides the necessary preconditions for the diathesis-stress model, which says the addition of an acute stressor to a weakened or predisposed system can lead to disease development. The paper also documents the evolving measurement of stress to better understand the stress-disease relationship, helping to resolve conflicting results between studies. The Developmental Model of Stress was combined with clinician insight and patient reports to build an integrative framework for understanding the role of stress in the development and progression of multiple sclerosis (MS). It includes the first mapping of maladaptive beliefs and behaviors arising from developmental challenges that are common to people with MS. An initial comparison shows these may be distinct from those of people with other chronic diseases. These beliefs and behaviors form the predisposing factors and contribute to the triggering factors, which are the acute stressors triggering disease onset. These often took two forms, a prolonged incident experienced as feeling trapped or stuck, and threat of a breach in a relationship. The reinforcing factors add the stress of a chronic disease with a poor prognosis and seemingly random symptom fluctuation, still managed with the same beliefs and behaviors developed in childhood, increasing physiological dysregulation and symptom severity. A pilot study is described in which these three categories of stress factors in MS were explicitly addressed. This study noted clinically important improvements in physical and mental well-being, providing preliminary support for the Developmental Model. Future research might expand on the pilot using a more robust sample and design.

Sensitivity of conventional cognitive tests in multiple sclerosis: Application of item response theory

BACKGROUND

Cognitive impairment (CI) is common in Multiple Sclerosis (MS), and its prevalence rate ranges between 22% and 70%. Because CI significantly impacts vocational status, caregiver burden, and quality of life, an accurate neuropsychological assessment is required. Three widely used and validated batteries for MS-associated CI are the Brief Repeatable Neuropsychological Battery (BRN-B), the Minimal Assessment of Cognitive Function (MACFIMS), and the Brief International Cognitive Assessment (BICAMS). Although similar, these batteries differ in time-consuming and in specific tests employed. This study aims to assess the sensitivity of cognitive tests included in these batteries through an Item Response Theory approach.

METHODS

Ninety-seven patients with MS and 91 demographically matched controls (HC) were consecutively assessed using the three neuropsychological batteries (i.e., BRN-B, MACFIMS, and BICAMS). Continuous Response Model (CRM) was used to identify the cognitive test(s) that best discriminate patients with MS from HC. Receiver Operating Characteristic (ROC) curve analysis was used to determine the accuracy of the CRM results.

RESULTS

Cognitive tests loaded on two different latent variables: the 'higher-order executive functioning,' consisting of tests assessing concept formation, problem-solving, and inhibitory control, and the 'memory and information processing speed,' comprising tests assessing long-term, working memory, and information processing speed. The Delis Kaplan Executive Functioning System-Sorting Test and the Stroop Test were the most sensitive tests in differentiating cognitive functioning between MS and HC.

CONCLUSIONS

This study confirms the importance of including a more extensive executive assessment in MS clinical practice since higher-order executive functions (e.g., abstraction and inhibitory control) significantly impact patients' quality of life and functional autonomy. Clinical implications of careful dissection of executive functioning in MS neuropsychological assessment are discussed.

Computational basis of decision-making impairment in multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is commonly associated with decision-making, neurocognitive impairments, and mood and motivational symptoms. However, their relationship may be obscured by traditional scoring methods.

OBJECTIVES

To study the computational basis underlying decision-making impairments in MS and their interaction with neurocognitive and neuropsychiatric measures.

METHODS

Twenty-nine MS patients and 26 matched control subjects completed a computer version of the Iowa Gambling Task (IGT). Participants underwent neurocognitive evaluation using an expanded version of the Brief Repeatable Battery. Hierarchical Bayesian Analysis was used to estimate three established computational models to compare parameters between groups.

RESULTS

Patients showed increased learning rate and reduced loss-aversion during decision-making relative to control subjects. These alterations were associated with: (1) reduced net gains in the IGT; (2) processing speed, executive functioning and memory impairments; and (3) higher levels of depression and current apathy.

CONCLUSION

Decision-making deficits in MS patients could be described by the interplay between latent computational processes, neurocognitive impairments, and mood/motivational symptoms.

The Agony of Choice? Preserved Affective Decision Making in Early Multiple Sclerosis

Background: Cognitive impairment (CI) is an early and frequent symptom of multiple sclerosis (MS). Likewise, affective symptoms (e.g., depression and anxiety) and alterations in the processing of emotional stimuli have been frequently reported. Thus, abilities that integrate affective and cognitive processes such as decision making (DM) based on affective feedback are potentially valuable early diagnostic markers for MS. The available research on this topic, however, is still inconclusive and suffers from methodological issues. Methods: We compared DM ability in a clinically homogeneous cohort of 24 patients with early relapsing-remitting MS (RRMS) and 59 age-matched healthy controls (HCs). A modified version of the Iowa gambling task (IGT) allowed us to control for individual differences in search strategies during the risk exploration phase. Besides standard IGT measures (netscore, obtained play money, and learning index), we also examined reaction times and post-error slowing (PES) patterns as a proxy for abnormalities in the processing of affective feedback. Results: The performance of patients did not significantly deviate from HCs in any standard parameter of the modified IGT. Furthermore, although RRMS patients reacted significantly slower than HCs overall, we found similar patterns of PES in both groups, suggesting similarly efficient processing of affective feedback. Conclusion: We conclude that there is no specific deficit in affective feedback processing in early RRMS. Previous findings of IGT impairments in this patient group may thus not represent a genuine deficit in affective DM but rather be related to sample characteristics, general CI, and/or differences in individual search strategies. Future research should explore the potential influence of lesion volumes and locations on DM ability by employing brain imaging techniques.

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.

A Systematic Review of Discrete-Choice Experiments and Conjoint Analysis Studies in People with Multiple Sclerosis

BACKGROUND

Multiple sclerosis (MS) is a chronic disabling, inflammatory, and degenerative disease of the central nervous system that, in most cases, requires long-term disease-modifying treatment (DMT). The drugs used vary in efficacy and adverse effect profiles. Several studies have used attribute-based stated-preference methods, primarily to investigate patient preferences for initiating or escalating DMT.

OBJECTIVES

To conduct a systematic review of attribute-based stated-preference studies in people with MS to identify common methods employed and to assess study quality, with reference to the specific challenges of this disease area.

METHODS

We conducted a systematic search for studies related to attribute-based stated-preference and MS in multiple databases, including Cochrane and MEDLINE. Studies were included if they were published in a peer-reviewed journal, were on the topic of MS, and used a survey methodology that measured stated preferences for attributes of a whole. Analysis was conducted using narrative synthesis and summary statistics. Study quality was judged against the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) conjoint analysis checklist.

RESULTS

We identified 16 relevant articles reporting 17 separate studies, all but one focusing on DMTs. Most studies were discrete-choice experiments. Study quality was generally high, but we recommend the following: (1) that consideration of sample sizes be improved, (2) that survey design choices be justified and documented, (3) that qualitative approaches for attribute and level selection be incorporated to better involve patients, and (4) that reporting of experimental practice be improved. The effects of DMTs on reproduction and the impact of how risk and uncertainty are presented were identified as neglected research topics. The ISPOR conjoint analysis checklist was found to be unsuitable for the assessment of study quality.

CONCLUSION

Attribute-based stated preference is a useful method with which to examine the preferences of people with MS in their choice of DMT. However, further research embracing the methodological recommendations identified, particularly greater use of qualitative methods in attribute development, is needed.

Information provision for people with multiple sclerosis

BACKGROUND

People with multiple sclerosis (MS) are confronted with a number of important uncertainties concerning many aspects of the disease. These include diagnosis, prognosis, disease course, disease-modifying therapies, symptomatic therapies, and non-pharmacological interventions, among others. While people with MS demand adequate information to be able to actively participate in medical decision making and to self manage their disease, it has been shown that patients' disease-related knowledge is poor, therefore guidelines recommend clear and concise high-quality information at all stages of the disease. Several studies have outlined communication and information deficits in the care of people with MS. However, only a few information and decision support programmes have been published.

OBJECTIVES

The primary objectives of this updated review was to evaluate the effectiveness of information provision interventions for people with MS that aim to promote informed choice and improve patient-relevant outcomes, Further objectives were to evaluate the components and the developmental processes of the complex interventions used, to highlight the quantity and the certainty of the research evidence available, and to set an agenda for future research.

SEARCH METHODS

For this update, we searched the Cochrane Multiple Sclerosis and Rare Diseases of the Central Nervous System Group Specialised Register, which contains trials from CENTRAL (the Cochrane Library 2017, Issue 11), MEDLINE, Embase, CINAHL, LILACS, PEDro, and clinical trials registries (29 November 2017) as well as other sources. We also searched reference lists of identified articles and contacted trialists.

SELECTION CRITERIA

Randomised controlled trials (RCTs), cluster-randomised controlled trials, and quasi-randomised trials comparing information provision for people with MS or suspected MS (intervention groups) with usual care or other types of information provision (control groups) were eligible.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the retrieved articles for relevance and methodological quality and extracted data. Critical appraisal of studies addressed the risk of selection bias, performance bias, attrition bias, and detection bias. We contacted authors of relevant studies for additional information.

MAIN RESULTS

We identified one new RCT (73 participants), which when added to the 10 previously included RCTs resulted in a total of 11 RCTs that met the inclusion criteria and were analysed (1387 participants overall; mean age, range: 31 to 51; percentage women, range: 63% to 100%; percentage relapsing-remitting MS course, range: 45% to 100%). The interventions addressed a variety of topics using different approaches for information provision in different settings. Topics included disease-modifying therapy, relapse management, self care strategies, fatigue management, family planning, and general health promotion. The active intervention components included decision aids, decision coaching, educational programmes, self care programmes, and personal interviews with physicians. All studies used one or more components, but the number and extent differed markedly between studies. The studies had a variable risk of bias. We did not perform meta-analyses due to marked clinical heterogeneity. All five studies assessing MS-related knowledge (505 participants; moderate-certainty evidence) detected significant differences between groups as a result of the interventions, indicating that information provision may successfully increase participants' knowledge. There were mixed results on decision making (five studies, 793 participants; low-certainty evidence) and quality of life (six studies, 671 participants; low-certainty evidence). No adverse events were detected in the seven studies reporting this outcome.

AUTHORS' CONCLUSIONS

Information provision for people with MS seems to increase disease-related knowledge, with less clear results on decision making and quality of life. The included studies in this review reported no negative side effects of providing disease-related information to people with MS. Interpretation of study results remains challenging due to the marked heterogeneity of interventions and outcome measures.

Neural Correlates of Outcome Anticipation in Multiple Sclerosis

Outcome anticipation is not only a mental preparation for upcoming consequences, but also an essential component of learning and decision-making. Thus, anticipation of consequences is a key process in everyday functioning. The striatum and the ventromedial prefrontal cortex are among the key regions that have been shown to be involved in outcome anticipation. However, while structural abnormalities of these regions as well as altered decision-making have been noted in individuals with multiple sclerosis (MS), neural correlates of outcome anticipation have not been explored in this population. Thus, we examined the neural correlates of outcome anticipation in MS by analyzing brain activation in individuals with MS while they performed a modified version of a card-guessing task. Seventeen MS and 13 healthy controls performed the task while functional magnetic resonance imaging (fMRI) was obtained. To achieve maximal anticipatory response and prevent the possibility of differential performance on the task, participants were presented with monetary rewards only on 50% of the trials. While replicating previous evidence of structural abnormalities of the striatum in MS, our results further showed that individuals with MS exhibited greater activation in the putamen, right hippocampus, and posterior cingulate cortex during outcome anticipation compared to healthy controls. Furthermore, even though there was no strategy that participants could learn in order to predict outcomes, 76% of participants with MS indicated that they used strategies while performing the task. We thus propose that the increased neural activation observed in MS during outcome anticipation might be explained by a failure in recognizing the lack of regularity in the task structure that could result in using strategies to perform the task.

Decision-Making in Multiple Sclerosis Patients: A Systematic Review

Background

Multiple sclerosis (MS) is frequently associated with cognitive and behavioural deficits. A growing number of studies suggest an impact of MS on decision-making abilities. The aim of this systematic review was to assess if (1) performance of MS patients in decision-making tasks was consistently different from controls and (2) whether this modification was associated with cognitive dysfunction and emotional alterations.

Methods

The search was conducted on Pubmed/Medline database. 12 studies evaluating the difference between MS patients and healthy controls using validated decision-making tasks were included. Outcomes considered were quantitative (net scores) and qualitative measurements (deliberation time and learning from feedback).

Results

Quantitative and qualitative decision-making impairment in MS was present in 64.7% of measurements. Patients were equally impaired in tasks for decision-making under risk and ambiguity. A correlation to other cognitive functions was present in 50% of cases, with the highest associations in the domains of processing speed and attentional capacity.

Conclusions

In MS patients, qualitative and quantitative modifications may be present in any kind of decision-making task and can appear independently of other cognitive measures. Since decision-making abilities have a significant impact on everyday life, this cognitive aspect has an influential importance in various MS-related treatment settings.

Decision-making in primary onset middle-age type 2 diabetes mellitus: a BOLD-fMRI study

Although type 2 diabetes mellitus (T2DM) is a well-recognized risk factor for dementia, the neural mechanisms that underlying cognitive impairment in T2DM remain unclear. We used functional magnetic resonance imaging (fMRI) during a computerized version of the Iowa Gambling Task to investigate the neural basis of decision making at the initial onset stage of T2DM. Eighteen newly diagnosed middle-aged T2DM patients, with no previous diabetic treatment history, and 18 matched controls were recruited. Results indicated that T2DM patients made more disadvantageous decisions than controls. Compared to healthy subjects, T2DM patients showed decreased activation in the ventral medial prefrontal cortex (VMPFC), orbitofrontal cortex (OFC) and anterior cingulate cortex, and increased activity in the dorsolateral prefrontal cortex, posterior cingulate cortex, insula and occipital lobes. IGT performance positively correlated with changes in brain activation in the VMPFC and OFC in both groups. Moreover, poor glycemic control was associated with decision-making function both in behavioral and brain activity in the VMPFC and OFC in patients. Conclusively, T2DM patients may suffer from weaknesses in their prefrontal cortex functions that lead to poorer decision-making under ambiguity, at least as assessed by the IGT.

Brain activity, regional gray matter loss, and decision-making in multiple sclerosis

BACKGROUND

Decision-making (DM) abilities deteriorate with multiple sclerosis (MS) disease progression which impairs everyday life and is thus clinically important.

OBJECTIVE

To investigate the underlying neurocognitive processes and their relation to regional gray matter (GM) loss induced by MS.

METHODS

We used a functional magnetic resonance imaging (fMRI) Iowa Gambling Task to measure DM-related brain activity in 36 MS patients and 21 healthy controls (HC). From this activity, we determined neural parameters of two cognitive stages, a deliberation ("choice") period preceding a choice and a post-choice ("feedback") stage reporting decision outcomes. These measures were related to DM separately in intact and damaged GM areas as determined by a voxel-based morphometry analysis.

RESULTS

Severely affected patients (with high lesion burden) showed worse DM-learning than HC ( t = -1.75, p = 0.045), moderately affected (low lesion burden) did not. Activity in the choice stage in intact insular ( t = 4.60, p_{Family-Wise Error [FWE] corrected} = 0.034), anterior cingulate ( t = 4.50, p_FWE = 0.044), and dorsolateral prefrontal areas ( t = 4.43, p_FWE = 0.049) and in insular areas with GM loss ( t = 3.78, p_FWE = 0.011) was positively linked to DM performance across patients with severe tissue damage and HC. Furthermore, activity in intact orbitofrontal areas was positively linked to DM-learning during the feedback stage across these participants ( t = 4.49, p_FWE = 0.032). During none of the stages, moderately affected patients showed higher activity than HC, which might have indicated preserved DM due to compensatory activity.

CONCLUSION

We identified dysregulated activity linked to impairment in specific cognitive stages of reward-related DM. The link of brain activity and impaired DM in areas with MS-induced GM loss suggests that this deficit might be tightly coupled to MS neuropathology.

Metabolic changes in normal appearing white matter in multiple sclerosis patients using multivoxel magnetic resonance spectroscopy imaging

Demyelination and axonal degeneration caused by multiple sclerosis (MS) exist in the white matter and not only in the lesion area. Magnetic resonance spectroscopy (MRS) could provide a unique insight into metabolic changes in the normal appearing white matter (NAWM). To evaluate the subtle axonal degeneration and delineate the spatial distribution of metabolite abnormalities in the NAWM in patients with MS. A total of 17 clinically definite relapsing-remitting MS (RRMS) patients and 21 healthy controls were enrolled in this study. 2D 1H magnetic resonance spectroscopic imaging (MRSI) performed at 3 Tesla was used to measure metabolite concentrations in the frontal-parietal-occipital NAWM. Ratios of N-acetyl-aspartate (NAA) and choline (Cho) to creatine (Cr) and Cho to NAA were calculated in each voxel. MS patients showed decreased NAA/Cr and increased Cho/NAA ratios in the NAWM compared to healthy controls. In the parietal NAWM, the extent of NAA/Cr decrease was significantly higher than that in the frontal and parietal-occipital NAWM. Decreased NAA in the NAWM would provide useful metabolic information for evaluation of disease progression in MS. The high extent of NAA decrease in the parietal NAWM helps improve the accuracy of the prediction.

Impairment of decision-making in multiple sclerosis: A neuroeconomic approach

OBJECTIVE

To assess the decision-making impairment in patients with multiple sclerosis (MS) and how they relate to other cognitive domains.

METHODS

We performed a cross-sectional analysis in 84 patients with MS, and 21 matched healthy controls using four tasks taken from behavioral economics: (1) risk preferences, (2) choice consistency, (3) delay of gratification, and (4) rate of learning. All tasks were conducted using real-world reward outcomes (food or money) in different real-life conditions. Participants underwent cognitive examination using the Brief Repeatable Battery-Neuropsychology.

RESULTS

Patients showed higher risk aversion (general propensity to choose the lottery was 0.51 vs 0.64, p = 0.009), a trend to choose more immediate rewards over larger but delayed rewards ( p = 0.108), and had longer reactions times ( p = 0.033). Choice consistency and learning rates were not different between groups. Progressive patients chose slower than relapsing patients. In relation to general cognitive impairments, we found correlations between impaired decision-making and impaired verbal memory ( r = 0.29, p = 0.009), visual memory ( r = -0.37, p = 0.001), and reduced processing speed ( r = -0.32, p = 0.001). Normalized gray matter volume correlated with deliberation time ( r = -0.32, p = 0.005).

CONCLUSION

Patients with MS suffer significant decision-making impairments, even at the early stages of the disease, and may affect patients' quality and social life.

Decision-making under explicit risk is impaired in multiple sclerosis: relationships with ventricular width and disease disability

BACKGROUND

Decision-making is an essential function of everyday life. Decision-making under explicit risk requires developing advantageous decision strategies based on fixed outcomes (e.g., probabilities of winning or losing a bet). Decision-making and its neural substrates have been rarely studied in MS. We expected performance in decision-making under risk to be lowered in MS patients, and negatively correlated with disease-related disability, cognition, and ventricular width.

METHODS

Three groups were included: 32 MS patients and 20 healthy controls were examined with conventional neuropsychological tests and the Game-of-Dice Task (GDT) assessing decision-making under explicit risk. Linear 2-D ventricular width was assessed on MS patients' clinical MRIs and compared to a third group, 20 non-MS neurological control patients.

RESULTS

Compared to healthy controls, MS patients showed impaired GDT and neuropsychological performance, depending on the MS-subtype (relapsing-remitting (RR), n = 22; secondary progressive, n = 10) and disability severity among RR-MS patients. In MS patients, GDT performance correlated with processing speed, intercaudate ratio, and third ventricle ratio (p's < 0.05). Mediation analysis showed that the link between GDT performance and processing speed was fully explained by ventricular size.

CONCLUSION

Decision-making under explicit risk was reduced in MS patients, but only those with more pronounced disability. Independent of processing speed, decision-making under explicit risk correlates inversely with central atrophy in MS.

Cognitive correlates of under-ambiguity and under-risk decision making in high-functioning patients with relapsing remitting multiple sclerosis

INTRODUCTION

Impairment of decision making in relapsing remitting multiple sclerosis is still controversial, and its neuropsychological correlates have never been explored thoroughly, especially in patients with minimal physical and cognitive deficits. In the present study we investigated the cognitive underpinnings of decision making under ambiguous and explicit conditions in patients with very mild relapsing remitting multiple sclerosis, using a dice and a card gambling game.

METHOD

The study sample included 60 patients and 35 healthy subjects. In the Game of Dice Task, winning and losing probabilities are obvious to the subject, while in the Iowa Gambling Task they are initially ambiguous and have to be gradually identified. Performance at the two tasks was correlated with scores obtained at tests investigating cognitive processing speed, memory, language and executive functions.

RESULTS

Patients' performance did not differ from that of controls at either gambling task. There was only a trend for them to be significantly slower than healthy subjects in progressively recognizing advantageous decks in the Iowa Gambling Task. While the Game of Dice was unrelated to neuropsychological tests, predictors of performance at the Iowa task were Letter Fluency and the Symbol Digit Modalities Test for the initial, under-ambiguity, trials and the Wisconsin Card Sorting Test for the last, purely under-risk, trials.

CONCLUSIONS

Our results suggest that high-functioning patients with relapsing remitting multiple sclerosis are substantially capable of making advantageous decisions, even if they may be slower in processing options and shifting strategy when selection criteria are not explicit.