Dana Serafin

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.

Cognitive Impairment Occurs in Children and Adolescents With Multiple Sclerosis Results From a United States Network

In the largest sample studied to date, we measured cognitive functioning in children and adolescents with pediatric multiple sclerosis (n = 187) as well as those with clinically isolated syndrome (n = 44). Participants were consecutively enrolled from six United States Pediatric Multiple Sclerosis Centers of Excellence. Participants had a mean of 14.8 ± 2.6 years of age and an average disease duration of 1.9 ± 2.2 years. A total of 65 (35%) children with multiple sclerosis and 8 (18%) with clinically isolated syndrome met criteria for cognitive impairment. The most frequent areas involved were fine motor coordination (54%), visuomotor integration (50%), and speeded information processing (35%). A diagnosis of multiple sclerosis (odds ratio = 3.60, confidence interval = 1.07, 12.36, P = .04) and overall neurologic disability (odds ratio = 1.47, confidence interval = 1.10, 2.10, P = .03) were the only independent predictors of cognitive impairment. Cognitive impairment may occur early in these patients, and prompt recognition is critical for their care.

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.

Psychiatric diagnoses and cognitive impairment in pediatric multiple sclerosis

Background: Pediatric multiple sclerosis (MS) represents approximately 5% of the MS population; information regarding clinical features is slowly accumulating. Cognitive and psychiatric impairments frequently occur, but remain poorly understood. Objectives: To describe psychiatric diagnoses among children with MS referred for psychiatric assessment and their relation to cognitive impairment. Methods: Forty-five pediatric MS patients (aged 8 to 17 years) were referred for outpatient psychiatric evaluation including a psychiatric interview (K-SADS), a clinician-based global assessment of functioning (Children’s Global Assessment Scale, CGAS), a neurologic examination including the Expanded Disability Status Scale (EDSS), and a neuropsychological test battery. Results: The most common categories of psychiatric diagnoses were anxiety disorders (n=15), attention deficit hyperactivity disorder (ADHD, n=12), and mood disorders (n=11). Cognitive impairment was classified in 20/25 (80%) of patients meeting criteria for a psychiatric disorder versus 11/20 (55%) of those without psychiatric disorder (p=0.08). Those diagnosed with anxiety or mood disorder had the highest frequency of cognitive impairment, with a significantly higher rate when compared with those with psychiatric diagnoses in other categories (p=0.05). Conclusions: A variety of psychiatric diagnoses can occur in children with pediatric MS. Many of these children also had cognitive impairment, particularly those in the mood and anxiety groups.

Visual-cognitive processing deficits in pediatric multiple sclerosis

Background: Children with multiple sclerosis (MS) can suffer significant cognitive deficits. This study investigates the sensitivity and validity in pediatric MS of two visual processing tests borrowed from the adult literature, the Brief Visuospatial Memory Test-Revised (BVMTR) and the Symbol Digit Modalities Test (SDMT). Objective: To test the hypothesis that visual processing is disproportionately impacted in pediatric MS by comparing performance with that of healthy controls on the BVMTR and SDMT. Methods: We studied 88 participants (43 MS, 45 controls) using a neuropsychological assessment battery including measures of intelligence, language, visual memory, and processing speed. Patients and demographically matched controls were compared to determine which tests are most sensitive in pediatric MS. Results: Statistically significant differences were found between the MS and control groups on BVMTR Total Learning (t (84) = 4.04, p < 0.001, d = 0.87), BVMTR Delayed Recall (t (84) = 4.45, p < 0.001, d = 0.96), and SDMT (t (38) = 2.19, p = 0.035, d = 0.69). No significant differences were found between groups on confrontation naming or general intellectual ability. Validity coefficients exploring correlation between BVMTR, SDMT, and disease characteristics were consistent with the adult literature. Conclusions: This study found that BVMTR and SDMT may be useful in assessing children and adolescents with MS.

Metabolomic approach to human brain spectroscopy identifies associations between clinical features and the frontal lobe metabolome in multiple sclerosis

Proton magnetic resonance spectroscopy ((1)H-MRS) is capable of noninvasively detecting metabolic changes that occur in the brain tissue in vivo. Its clinical utility has been limited so far, however, by analytic methods that focus on independently evaluated metabolites and require prior knowledge about which metabolites to examine. Here, we applied advanced computational methodologies from the field of metabolomics, specifically partial least squares discriminant analysis and orthogonal partial least squares, to in vivo (1)H-MRS from frontal lobe white matter of 27 patients with relapsing-remitting multiple sclerosis (RRMS) and 14 healthy controls. We chose RRMS, a chronic demyelinating disorder of the central nervous system, because its complex pathology and variable disease course make the need for reliable biomarkers of disease progression more pressing. We show that in vivo MRS data, when analyzed by multivariate statistical methods, can provide reliable, distinct profiles of MRS-detectable metabolites in different patient populations. Specifically, we find that brain tissue in RRMS patients deviates significantly in its metabolic profile from that of healthy controls, even though it appears normal by standard MRI techniques. We also identify, using statistical means, the metabolic signatures of certain clinical features common in RRMS, such as disability score, cognitive impairments, and response to stress. This approach to human in vivo MRS data should promote understanding of the specific metabolic changes accompanying disease pathogenesis, and could provide biomarkers of disease progression that would be useful in clinical trials.

Pediatric Multiple Sclerosis: What we know and where are we headed?

Multiple Sclerosis (MS), an autoimmune mediated disease of the central nervous system, has historically been considered a disease of young adulthood. However, there has been increasing recognition that the disease can occur in adolescence and even early childhood and recent years have witnessed a surge of studies documenting the clinical features of the disease as it pertains to this young population. The purpose of this article is to review the literature on MS in childhood and adolescence, including the clinical presentation of the disease in this group, neuropathology and pathogenesis, magnetic resonance imaging findings, as well as neuropsychological and psychosocial considerations.

Fatigue in multiple sclerosis

Background: Fatigue is the most commonly reported symptom in multiple sclerosis (MS). Purpose: This brief narrative review addresses the clinical features, pathophysiology, and management of MS fatigue, as well as the varied approaches to its definition and measurement. Methods: A literature search was conducted through Medline of studies published since 1984, with a focus on findings reported since 2008. Results: Studies of MS fatigue have primarily relied on the definition of fatigue as a subjective sense of tiredness measured through self-report. Additional studies have measured fatigability in MS, as demonstrated by a decline in cognitive or motor performance over time. The pathogenesis of fatigue remains poorly understood but disease characteristics, including structural and physiologic cerebral alterations as well as immune, endocrine, and psychological factors, may all contribute to its expression. Fatigue therapy has included pharmacologic approaches which have had either methodological limitations (e.g., small sample sizes) or inconclusive results and non-pharmacologic interventions, some of which have been effective in reducing fatigue. Conclusions: Fatigue remains a challenging symptom in MS. The most effective measurement approaches will likely be multidimensional and include both subjective and objective indicators, whereas therapy will likely require more than one type of intervention.