Christopher Christodoulou

Donepezil improved memory in multiple sclerosis in a randomized clinical trial

Objective: To determine the effect of donepezil in treating memory and cognitive dysfunction in multiple sclerosis (MS). Methods: This single-center double-blind placebo-controlled clinical trial evaluated 69 MS patients with cognitive impairment who were randomly assigned to receive a 24-week treatment course of either donepezil (10 mg daily) or placebo. Patients underwent neuropsychological assessment at baseline and after 24 weeks of treatment. The primary outcome was change in verbal learning and memory on the Selective Reminding Test (SRT). Secondary outcomes included other tests of cognitive function, patient-reported change in memory, and clinician-reported impression of cognitive change. Results: Donepezil-treated patients showed significant improvement in memory performance on the SRT compared to placebo (p = 0.043). The benefit of donepezil remained significant after controlling for various covariates including age, Expanded Disability Status Scale, baseline SRT score, reading ability, MS subtype, and sex. Donepezil-treated patients did not show significant improvements on other cognitive tests, but were more than twice as likely to report memory improvement than those in the placebo group (p = 0.006). The clinician also reported cognitive improvement in almost twice as many donepezil vs placebo patients (p = 0.036). No serious adverse events related to study medication occurred, although more donepezil (34.3%) than placebo (8.8%) subjects reported unusual/abnormal dreams (p = 0.010). Conclusions: Donepezil improved memory in MS patients with initial cognitive impairment in a single center clinical trial. A larger multicenter investigation of donepezil in MS is warranted in order to more definitively assess the efficacy of this intervention.

Cognitive performance and MR markers of cerebral injury in cognitively impaired MS patients

Objective: To relate neuropsychological performance to measures of cerebral injury in persons with MS selected for cognitive impairment. Methods: Participants were 37 individuals with relapsing–remitting (59.5%) and secondary progressive (40.5%) MS. They were tested at baseline as part of a clinical trial to enhance cognition with an acetylcholinesterase inhibitor. Eligibility criteria included at least mild cognitive impairment on a verbal learning and memory task. A modified Brief Repeatable Battery of Neuropsychological Tests formed the core of the behavioral protocol. Neuroimaging measures were central (ventricular) cerebral atrophy, lesion volume, and ratios of N -acetyl aspartate (NAA) to both creatine and choline. Results: A clear, consistent relation was found between cognitive and MR measures. Among neuroimaging measures, central atrophy displayed the highest correlations with cognition, accounting for approximately half the variance in overall cognitive performance. NAA ratios in right hemisphere sites displayed larger correlations than those on the left. Multiple regression models combining the MR measures accounted for well over half the variance in overall cognitive performance. The Symbol Digit Modalities Test was the neuropsychological task most strongly associated with the neuroimaging variables. Conclusions: If a strong and stable association can be firmly established between cognitive and MR variables in appropriate subsets of MS patients, it might aid in the investigation of interventions to enhance cognition and modify the course of the disease.

Cognitive functioning in children and adolescents with multiple sclerosis

Objective: To examine cognitive functioning in children with multiple sclerosis (MS). Methods: The authors examined the neuropsychological profile of 37 children with a diagnosis of clinically definite MS and assessed the associations between cognitive function and clinical features. Results: Of 37 children and adolescents evaluated, 35% demonstrated significant cognitive impairment. Cognitive functioning was strongly related to several clinical variables, including current Expanded Disability Status Scale, total number of relapses, and total disease length. The consequences of MS adversely affected academic functioning in over a third of the children. Conclusions: Cognitive deficits occur in children with multiple sclerosis. Comprehensive treatment planning should involve recognition that they may require academic accommodations for their education.

How item banks and their application can influence measurement practice in rehabilitation medicine: a PROMIS fatigue item bank example.

OBJECTIVE To illustrate how measurement practices can be advanced by using as an example the fatigue item bank (FIB) and its applications (short forms and computerized adaptive testing [CAT]) that were developed through the National Institutes of Health Patient Reported Outcomes Measurement Information System (PROMIS) Cooperative Group. DESIGN Psychometric analysis of data collected by an Internet survey company using item response theory-related techniques. SETTING A U.S. general population representative sample collected through the Internet. PARTICIPANTS Respondents used for dimensionality evaluation of the PROMIS FIB (N=603) and item calibrations (N=14,931). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Fatigue items (112) developed by the PROMIS fatigue domain working group, 13-item Functional Assessment of Chronic Illness Therapy-Fatigue, and 4-item Medical Outcomes Study 36-Item Short Form Health Survey Vitality scale. RESULTS The PROMIS FIB version 1, which consists of 95 items, showed acceptable psychometric properties. CAT showed consistently better precision than short forms. However, all 3 short forms showed good precision for most participants in that more than 95% of the sample could be measured precisely with reliability greater than 0.9. CONCLUSIONS Measurement practice can be advanced by using a psychometrically sound measurement tool and its applications. This example shows that CAT and short forms derived from the PROMIS FIB can reliably estimate fatigue reported by the U.S. general population. Evaluation in clinical populations is warranted before the item bank can be used for clinical trials.

Multiple sclerosis-associated fatigue

Fatigue is an extremely prevalent issue for multiple sclerosis (MS) patients. Fatigue can affect quality of life, depression, anxiety, motor function and sleep patterns. There are a number of available rating scales designed to detect and assess fatigue. However, the pathophysiology of fatigue is still not completely understood and the treatment of this symptom remains difficult. A number of clinical trials for fatigue in MS have shown some benefit with different interventions, including medication, physical activity and cognitive–behavioral therapy. Nonetheless, further research and the development of more targeted therapies are needed to improve the management of fatigue.

Unemployment in multiple sclerosis: the contribution of personality and disease

Background: Multiple sclerosis (MS) is the leading cause of neurological disability among young and middle-aged adults. One of the most devastating consequences of MS in this relatively young population group is unemployment. Although certain demographic and disease factors have been associated with employment, few studies have examined the contribution of person-specific factors, such as personality. Objective: The goal of this study was to determine the extent to which personality, demographics, and clinical measures contribute to unemployment in MS. Method: A total of 101 individuals with MS who were enrolled in a clinical trial on cognition underwent a brief neuropsychological battery and completed questionnaires related to vocation, mood, fatigue, and personality. Neurological impairment was measured with the Expanded Disability Status Scale (EDSS). Results: Employment status was related with disease duration, MS subtype, level of neurological impairment, fatigue, performance on measures assessing information processing speed (Symbol Digit Modalities Test (SDMT)), learning and memory (Selective Reminding Test), and the personality characteristic of persistence. Based on a forward logistic regression analysis, EDSS, SDMT, and persistence were the strongest predictors of employment status. Conclusions: These findings underscore the importance of personality on outcomes in MS and point to the need for more clinical attention and research in this area.

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 participants impression of memory change. Secondary outcomes included changes on other neuropsychological tests and the evaluating clinicians 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 clinicians 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.

Multiple white matter tract abnormalities underlie cognitive impairment in RRMS.

Diffusion tensor imaging (DTI) is a sensitive tool for detecting microstructural tissue damage in vivo. In this study, we investigated DTI abnormalities in individuals with relapsing remitting multiple sclerosis (RRMS) and examined the relations between imaging-based measures of white matter injury and cognitive impairment. DTI-derived metrics using tract-based spatial statistics (TBSS) were compared between 37 individuals with RRMS and 20 healthy controls. Cognitive impairment was assessed with three standard tests: the Symbol Digit Modalities Test (SDMT), which measures cognitive processing speed and visual working memory, the Rey Auditory Verbal Learning Test (RAVLT), which examines verbal memory, and the Paced Auditory Serial Addition Test (PASAT), which assesses sustained attention and working memory. Correlations between DTI-metrics and cognition were explored in regions demonstrating significant differences between the RRMS patients and the control group. Lower fractional anisotropy (FA) was found in RRMS participants compared to controls across the tract skeleton (0.40 ± 0.03 vs. 0.43 ± 0.01, p<0.01). In areas of reduced FA, mean diffusivity was increased and was dominated by increased radial diffusivity with no significant change in axial diffusivity, an indication of the role of damage to CNS myelin in MS pathology. In the RRMS group, voxelwise correlations were found between FA reduction and cognitive impairment in cognitively-relevant tracts, predominantly in the posterior thalamic radiation, the sagittal stratum, and the corpus callosum; the strongest correlations were with SDMT measures, with contributions to these associations from both lesion and normal-appearing white matter. Moreover, results using threshold-free cluster enhancement (TFCE) showed more widespread white matter involvement compared to cluster-based thresholding. These findings indicate the important role for DTI in delineating mechanisms underlying MS-associated cognitive impairment and suggest that DTI could play a critical role in monitoring the clinical and cognitive effects of the disease.

Cognitive interviewing in the evaluation of fatigue items: Results from the patient-reported outcomes measurement information system (PROMIS)

ObjectivesCognitive Interviewing (CI) is a technique increasingly used to obtain respondent feedback on potential items during questionnaire development. No standard guidelines exist by which to incorporate CI feedback in deciding to retain, revise, or eliminate potential items. We used CI in developing fatigue items for the National Institutes of Health (NIH) Patient-Reported Outcomes Measurement Information System (PROMIS) Roadmap initiative. Our aims were to describe the CI process, formally evaluate the utility of decisions made on the basis of CI, and offer suggestions for future research.MethodsParticipants were 22 patients with a diverse range of chronic health conditions. During CI, each participant provided feedback on a series of items. We then reviewed the CI data and decided whether to retain, revise, or eliminate each potential item. Following this, we developed or adopted three quantitative methods to compare retained versus eliminated items.ResultsRetained items raised fewer serious concerns, were less likely to be viewed as non-applicable, and were less likely to display problems with clarity or to make incorrect assumptions about respondents.ConclusionsCI was useful in developing the PROMIS fatigue items and the methods used to judge CI for the present item set may be useful for future investigations.

Longitudinal Neuropsychological Assessment in Pediatric Multiple Sclerosis

Although Multiple Sclerosis (MS) occurring in childhood and adolescence has received increasing attention in recent years, the impact of the disease on cognitive function in this subgroup remains poorly understood. It has been posited that children and adolescents with MS may be particularly susceptible to cognitive dysfunction because the pathological processes, including inflammation, blood brain barrier breakdown, and demyelination, occur concurrently with ongoing myelination. Early work has documented that a number of these children present with cognitive deficits. However, there is no available information on the progression of these deficits, or on what clinical factors may predict further decline. The current article reviews what is currently known about pediatric MS and follows a cohort of pediatric MS patients and assesses cognitive function longitudinally. Participants were evaluated with a brief neuropsychological test battery on two separate occasions and correlational analyses assessed the relations between changes in cognition and several clinical variables including level of neurologic impairment, number of relapses prior to baseline assessment, number of interim relapses, age of disease onset, and disease length. The results indicate that a number of these patients experience further cognitive decline over time, or decline from previously normal functioning. Baseline level of neurologic disability was significantly correlated with changes in cognition. The number of interim relapses (i.e., relapses occurring between baseline assessment and re-evaluation) showed a modest relationship to changes in cognitive function, but this did not reach statistical significance.