Separate and Combined Influence of Cognitive Impairment and Dysarthria on Functional Communication in Multiple Sclerosis

PURPOSE

Dysarthria is a consequence of multiple sclerosis (MS) that can co-occur with cognitive impairment. Clinical management thus requires understanding the separate and combined effects of dysarthria and cognitive impairment on functional communication in MS. This study compared perceptual measures of intelligibility and speech severity that capture functional communication deficits for 4 operationally defined groups with MS. The relationship between communication participation and perceptual measures was also examined.

METHOD

Forty-eight adults with MS and 12 healthy controls participated. Cognitive testing and dysarthria diagnosis determined group assignment: (a) MS with cognitive impairment (MSCI), (b) MS with a diagnosis of dysarthria and no cognitive impairment (MSDYS), (c) MS with dysarthria and cognitive impairment (MSDYS + CI), and (d) MS without dysarthria or cognitive impairment (MS). Sentence Intelligibility Test scores, scaled speech severity obtained from the "Grandfather Passage," and Communication Participation Item Bank (CPIB) scores were analyzed.

RESULTS

Sentence Intelligibility Test scores approached 100% for all groups. Speech severity was greater for the MSDYS + CI and MSDYS groups versus controls. CPIB scores were greatest for the MSDYS + CI group and were not significantly correlated with either perceptual measure.

CONCLUSIONS

The CPIB and speech severity were sensitive to aspects of communication problems for some groups with MS not reflected in a measure of sentence intelligibility. Findings suggest the importance of employing a variety of measures to capture functional communication problems experienced by persons with MS.

Impact of Focal White Matter Damage on Localized Subcortical Gray Matter Atrophy in Multiple Sclerosis: A 5-Year Study

BACKGROUND AND PURPOSE

It is unclear to what extent subcortical gray matter atrophy is a primary process as opposed to a result of focal white matter damage. Correlations between WM damage and atrophy of subcortical gray matter have been observed but may be partly attributable to indirect relationships between co-occurring processes arising from a common cause. Our aim was to cross-sectionally and longitudinally characterize the unique impact of focal WM damage on the atrophy of connected subcortical gray matter regions, beyond what is explainable by global disease progression.

MATERIALS AND METHODS

One hundred seventy-six individuals with MS and 47 healthy controls underwent MR imaging at baseline and 5 years later. Atrophy and lesion-based disruption of connected WM tracts were evaluated for 14 subcortical gray matter regions. Hierarchic regressions were applied, predicting regional atrophy from focal WM disruption, controlling for age, sex, disease duration, whole-brain volume, and T2-lesion volume.

RESULTS

When we controlled for whole-brain volume and T2-lesion volume, WM tract disruption explained little additional variance of subcortical gray matter atrophy and was a significant predictor for only 3 of 14 regions cross-sectionally (ΔR² = 0.004) and 5 regions longitudinally (ΔR² = 0.016). WM tract disruption was a significant predictor for even fewer regions when correcting for multiple comparisons.

CONCLUSIONS

WM tract disruption accounts for a small percentage of atrophy in connected subcortical gray matter when controlling for overall disease burden and is not the primary driver in most cases.

Thalamic white matter in multiple sclerosis: A combined diffusion-tensor imaging and quantitative susceptibility mapping study

Thalamic white matter (WM) injury in multiple sclerosis (MS) remains relatively poorly understood. Combining multiple imaging modalities, sensitive to different tissue properties, may aid in further characterizing thalamic damage. Forty-five MS patients and 17 demographically-matched healthy controls (HC) were scanned with 3T MRI to obtain quantitative measures of diffusivity and magnetic susceptibility. Participants underwent cognitive evaluation with the Brief International Cognitive Assessment for Multiple Sclerosis battery. Tract-based spatial statistics identified thalamic WM. Non-parametric combination (NPC) analysis was used to perform joint inference on fractional anisotropy (FA), mean diffusivity (MD) and magnetic susceptibility measures. The association of surrounding WM lesions and thalamic WM pathology was investigated with lesion probability mapping. Compared to HCs, the greatest extent of thalamic WM damage was reflected by the combination of increased MD and decreased magnetic susceptibility (63.0% of thalamic WM, peak p = .001). Controlling for thalamic volume resulted in decreased FA and magnetic susceptibility (34.1%, peak p = .004) as showing the greatest extent. In MS patients, the most widespread association with information processing speed was found with the combination of MD and magnetic susceptibility (67.6%, peak p = .0005), although this was not evident after controlling for thalamic volume. For memory measures, MD alone yielded the most widespread associations (45.9%, peak p = .012 or 76.7%, peak p = .001), even after considering thalamic volume, albeit with smaller percentages. White matter lesions were related to decreased FA (peak p = .0063) and increased MD (peak p = .007), but not magnetic susceptibility, of thalamic WM. Our study highlights the complex nature of thalamic pathology in MS.

White matter tract network disruption explains reduced conscientiousness in multiple sclerosis

Quantifying white matter (WM) tract disruption in people with multiple sclerosis (PwMS) provides a novel means for investigating the relationship between defective network connectivity and clinical markers. PwMS exhibit perturbations in personality, where decreased Conscientiousness is particularly prominent. This trait deficit influences disease trajectory and functional outcomes such as work capacity. We aimed to identify patterns of WM tract disruption related to decreased Conscientiousness in PwMS. Personality assessment and brain MRI were obtained in 133 PwMS and 49 age- and sex-matched healthy controls (HC). Lesion maps were applied to determine the severity of WM tract disruption between pairs of gray matter regions. Next, the Network-Based-Statistics tool was applied to identify structural networks whose disruption negatively correlates with Conscientiousness. Finally, to determine whether these networks explain unique variance above conventional MRI measures and cognition, regression models were applied controlling for age, sex, brain volume, T2-lesion volume, and cognition. Relative to HCs, PwMS exhibited lower Conscientiousness and slowed cognitive processing speed (p = .025, p = .006). Lower Conscientiousness in PwMS was significantly associated with WM tract disruption between frontal, frontal-parietal, and frontal-cingulate pathways in the left (p = .02) and right (p = .01) hemisphere. The mean disruption of these pathways explained unique additive variance in Conscientiousness, after accounting for conventional MRI markers of pathology and cognition (ΔR²  = .049, p = .029). Damage to WM tracts between frontal, frontal-parietal, and frontal-cingulate cortical regions is significantly correlated with reduced Conscientiousness in PwMS. Tract disruption within these networks explains decreased Conscientiousness observed in PwMS as compared with HCs.

Apolipoprotein E genotype impact on memory and attention in older persons: the moderating role of personality phenotype

OBJECTIVES

To determine if phenotypic personality traits modify the association of Apolipoprotein E (APOE) genotypes with different domains of cognitive function.

DESIGN

Cross-sectional.

METHODS

172 non-demented older adults were administered the NEO-Five Factor Inventory (NEO-FFI), a battery of neuropsychological tests assessing memory, attention, executive function, language, and visuospatial ability, and underwent APOE genotyping. Multivariate (multiple-dependent variable) regression models predicting cognitive domains tested APOE interactions with personality traits, adjusting for age, sex, and education.

RESULTS

The APOE ε4 allele showed small to modest main effects on memory and executive function (1/3 SD deficits for carriers, p < .05), with ε2 status evidencing minimal and non-significant benefit. Neuroticism interacted with both ε2 and ε4 alleles in associations with attention scores (p = .001), with ε2 benefits and ε4 deficits being marked at high Neuroticism (Mean [M] covariate-adjusted Z-score = .39 for ε2, -.47 for ε4). The association of ε4 with memory was moderated by Conscientiousness (p < .001), such that ε4 memory deficits were apparent at low Conscientiousness (M = -.56), but absent at high levels of Conscientiousness. Weaker patterns (p < .05) also suggested ε4-related detriments in executive function only at lower Conscientiousness, and ε2 memory benefits only at higher Openness.

CONCLUSIONS

Conscientiousness and Neuroticism moderate APOE associations with memory and executive function. As such, they may be useful phenotypic markers in refining the prognostic significance of this polymorphism. Effect-modifying personality traits also provide clues about behavioral and psychological factors that influence the cognitive impact of APOE. Copyright © 2017 John Wiley & Sons, Ltd.

Influence of nationality on the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS)

OBJECTIVE

In answer to the call for improved accessibility of neuropsychological services to the international community, the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS; MS) was validated in multiple, non-English-speaking countries. It was created to monitor processing speed and learning in MS patients, including abbreviated versions of the Symbol Digit Modalities Test, California Verbal Learning Test, 2nd Edition, and the Brief Visuospatial Memory Test, Revised. The objective of the present study was to examine whether participant nationality impacts performance above and beyond common demographic correlates.

METHOD

We combined published data-sets from Argentina, Brazil, Czech Republic, Iran, and the U.S.A. resulting in a database of 1,097 healthy adults, before examining the data via multiple regression.

RESULTS

Nationality significantly predicted performance on all three BICAMS tests after controlling for age and years of education. Interactions among the core predictor variables were non-significant.

CONCLUSION

We demonstrated that nationality significantly influences BICAMS performance and established the importance of the inclusion of a nationality variable when international norms for the BICAMS are constructed.

Validation of olfactory deficit as a biomarker of Alzheimer disease

BACKGROUND

We evaluated smell identification as a biomarker for Alzheimer disease (AD) by assessing its utility in differentiating normal aging from an amnestic disorder and determining its predictive value for conversion from amnestic mild cognitive impairment (aMCI) to AD.

METHODS

Cross-sectional study (AD = 262, aMCI = 110, controls = 194) measuring smell identification (University of Pennsylvania Smell Identification Test [UPSIT]) and cognitive status was performed, as well as longitudinal analysis of aMCI participants (n = 96) with at least 1 year follow-up (mean 477.6 ± 223.3 days), to determine conversion by National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria.

RESULTS

Odor identification and disease status were highly correlated after correcting for age, sex, and APOE (p < 0.001). Receiver operating characteristic (ROC)/area under the curve (AUC) was similar for the 40-item UPSIT, the top 10 smells in our study, and the 10-item subset previously proposed. Smeller/nonsmeller based on the 10-item subset with a cutoff of 7 (≤7, nonsmeller; >7, smeller) had a sensitivity and specificity of 88% and 71% for identifying AD and 74% sensitivity and 71% specificity for identifying an amnestic disorder. A total of 36.4% of participants with impaired olfaction and 17.3% with intact olfaction converted to AD (p = 0.03). The ROC/AUC for prediction of conversion to AD was 0.62.

CONCLUSIONS

Olfactory identification deficit is a useful screening tool for AD-related amnestic disorder, with sensitivity and specificity comparable to other established biomarkers, with benefits such as ease of administration and low cost. Olfactory identification deficit can be utilized to stratify risk of conversion from aMCI to AD and enrich clinical trials of disease-modifying therapy.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that smell identification (10-item UPSIT subset) accurately identifies patients with amnestic disorders.

Brain MRI atrophy quantification in MS: From methods to clinical application

Patients with the main clinical phenotypes of multiple sclerosis (MS) manifest varying degrees of brain atrophy beyond that of normal aging. Assessment of atrophy helps to distinguish clinically and cognitively deteriorating patients and predicts those who will have a less-favorable clinical outcome over the long term. Atrophy can be measured from brain MRI scans, and many technological improvements have been made over the last few years. Several software tools, with differing requirements on technical ability and levels of operator intervention, are currently available and have already been applied in research or clinical trial settings. Despite this, the measurement of atrophy in routine clinical practice remains an unmet need. After a short summary of the pathologic substrates of brain atrophy in MS, this review attempts to guide the clinician towards a better understanding of the methods currently used for quantifying brain atrophy in this condition. Important physiologic factors that affect brain volume measures are also considered. Finally, the most recent research on brain atrophy in MS is summarized, including whole brain and various compartments thereof (i.e., white matter, gray matter, selected CNS structures). Current methods provide sufficient precision for cohort studies, but are not adequate for confidently assessing changes in individual patients over the scale of months or a few years.

Identification of multiple sclerosis patients at highest risk of cognitive impairment using an integrated brain magnetic resonance imaging assessment approach

BACKGROUND AND PURPOSE

While impaired cognitive performance is common in multiple sclerosis (MS), it has been largely underdiagnosed. Here a magnetic resonance imaging (MRI) screening algorithm is proposed to identify patients at highest risk of cognitive impairment. The objective was to examine whether assessment of lesion burden together with whole brain atrophy on MRI improves our ability to identify cognitively impaired MS patients.

METHODS

Of the 1253 patients enrolled in the study, 1052 patients with all cognitive, volumetric MRI and clinical data available were included in the analysis. Brain MRI and neuropsychological assessment with the Brief International Cognitive Assessment for Multiple Sclerosis were performed. Multivariable logistic regression and individual prediction analysis were used to investigate the associations between MRI markers and cognitive impairment. The results of the primary analysis were validated at two subsequent time points (months 12 and 24).

RESULTS

The prevalence of cognitive impairment was greater in patients with low brain parenchymal fraction (BPF) (<0.85) and high T2 lesion volume (T2-LV) (>3.5 ml) than in patients with high BPF (>0.85) and low T2-LV (<3.5 ml), with an odds ratio (OR) of 6.5 (95% CI 4.4-9.5). Low BPF together with high T2-LV identified in 270 (25.7%) patients predicted cognitive impairment with 83% specificity, 82% negative predictive value, 51% sensitivity and 75% overall accuracy. The risk of confirmed cognitive decline over the follow-up was greater in patients with high T2-LV (OR 2.1; 95% CI 1.1-3.8) and low BPF (OR 2.6; 95% CI 1.4-4.7).

CONCLUSIONS

The integrated MRI assessment of lesion burden and brain atrophy may improve the stratification of MS patients who may benefit from cognitive assessment.

Executive Function and Personality Predict Instrumental Activities of Daily Living in Alzheimer Disease

OBJECTIVE

Previous research shows that executive function (EF) and personality independently predict functional decline. Our objective was to determine whether personality traits predict independence with instrumental activities of daily living (IADLs), after accounting for executive dysfunction, in a mixed sample of patients with amnestic mild cognitive impairment (MCI) and Alzheimer disease (AD).

METHODS

In a cross-sectional analysis at a university medical center, 63 healthy older adults (median age: 67.6 years; 71% women) and 119 patients (median age: 75.0 years; 58% women) with varying degrees of AD (probable AD: 85; possible AD: 3; amnestic MCI: 31) were studied. Standardized neuropsychological measures, NEO Five-Factor Inventory (NEO-FFI), and informant-report Lawton and Brody IADL scales were used. All participants underwent neuropsychological evaluation, including administration of self- and informant-report NEO-FFI. Patients additionally underwent neurologic examination, and their informants completed the Lawton and Brody IADL scale.

RESULTS

When testing the association between EF and personality on IADLs in the patient sample, conceptual card sorting, informant-report Openness, and informant-report Conscientiousness all significantly predicted IADLs, after accounting for age, education, and depression. In addition, a significant interaction showed that low Conscientiousness and executive dysfunction, in combination, can predict impairment of IADLs.

CONCLUSION

Personality has a unique association with IADLs in patients with AD pathology that is not explained by EF. The findings confirm prior speculation that personality, in addition to cognitive dysfunction, is a risk factor for functional decline. Early identification of vulnerable individuals may allow for intervention to prolong functional independence.

Cognitive impairment is associated with subcortical magnetic resonance imaging grey matter T2 hypointensity in multiple sclerosis

Grey matter hypointensity on T2-weighted magnetic resonance imaging (MRI) scans, suggesting iron deposition, has been described in multiple sclerosis (MS) and is related to physical disability, disease course and brain atrophy. We tested the hypothesis that subcortical grey matter T2 hypointensity is related to cognitive impairment after adjusting for the effect of MRI lesion and atrophy measures. We studied 33 patients with MS and 14 healthy controls. Normalized T2 signal intensity in the caudate, putamen, globus pallidus and thalamus, total brain T1-hypointense lesion volume (T1LV), fluid-attenuated inversion-recovery-hyperintense lesion volume (FLLV) and brain parenchymal fraction (BPF) were obtained quantitatively. A neuropsychological composite score (NCS) encompassed new learning, attention, working memory, spatial processing and executive function. In each of the regions of interest, the normalized T2 intensity was lower in the MS versus control group (all P <0.001). Regression modelling tested the relative association between all MRI variables and NCS. Globus pallidus T2 hypointensity was the only variable selected in the final model ( R2 = 0.301, P = 0.007). Pearson correlations between MRI and NCS were T1LV: r = -0.319; FLLV: r = -0.347; BPF: r = 0.374; T2 hypointensity of the caudate: r = 0.305; globus pallidus: r = 0.395; putamen: r = 0.321; and thalamus: r = 0.265. Basal ganglia T2 hypointensity and BPF demonstrated the strongest associations with cognitive impairment on individual cognitive subtests. Subcortical grey matter T2 hypointensity is related to cognitive impairment in MS, supporting the clinical relevance of T2 hypointensity as a biological marker of MS tissue damage. These data implicate a role for basal ganglia iron deposition in neuropsychological dysfunction.

A new assessment tool for patients with multiple sclerosis from Spanish-speaking countries: validation of the Brief International Cognitive Assessment for MS (BICAMS) in Argentina

BACKGROUND

The Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) is an international assessment tool for monitoring cognitive function in multiple sclerosis (MS) patients. BICAMS comprises the Symbol Digit Modalities Test (SDMT), the California Verbal Learning Test - Second Edition (CVLT II) and the Brief Visuospatial Memory Test - Revised (BVMT-R). Our objective was to validate and assess the reliability of BICAMS as applied in Argentina and to obtain normative data in Spanish for this population.

METHOD

The sample composed of 50 MS patients and 100 healthy controls (HC). In order to test its reliability, BICAMS was re-administered in a subset of 25 patients.

RESULTS

The sample's average age was 43.42 ± 10.17 years old, and average years of schooling were 14.86 ± 2.78. About 74% of the participants were women. The groups did not differ in age, years of schooling, or gender. The MS group performed significantly worse than the HC group across the three neuropsychological tests, yielding the following Cohen's d values: SDMT: .85; CVLT I: .87; and BVMT-R: .40. The mean raw scores for Argentina normative data were as follows: SDMT: 56.71 ± 10.85; CVLT I: 60.88 ± 10.46; and BVMT-R: 23.44 ± 5.84. Finally, test-retest reliability coefficients for each test were as follows: SDMT: r = .95; CVLT I: r = .87; and BVMT-R: r = .82.

CONCLUSION

This BICAMS version is reliable and useful as a monitoring tool for identifying MS patients with cognitive impairment.

Impact of Pharmacotherapy on Cognitive Dysfunction in Patients with Multiple Sclerosis

Cognitive impairment is a common symptom of multiple sclerosis (MS), adversely impacting many spheres of daily functioning. Yet the effectiveness of pharmacological interventions for cognitive impairment in MS is unclear. Clinicians and patients alike would benefit from formal guidelines regarding effective management of cognitive symptoms. We reviewed the background on the measurement, pathophysiology and risk factors for cognitive dysfunction in MS, and then examined the published clinical trials of pharmacotherapy, including both disease-modifying treatments (DMTs) and symptom-management therapies (SMTs). Our review of DMTs revealed only a single well-designed, randomized, controlled trial where intramuscular interferon (IFN)-β1a, administered once weekly, was compared with placebo. The results showed significant benefits in terms of cognitive processing speed and memory. Less convincing but promising data have shown the potential benefits of IFN-β1b and natalizumab. The literature on SMTs is replete with placebo-controlled, single-centre studies, with a failure to replicate initially promising results. The results for SMTs such as acetylcholinesterase inhibitors and psychostimulants are mixed. Some encouraging data show promise but not to a threshold of indication for standard clinical use. Numerous methodological factors hamper research in this area. Acknowledging the lack of firm conclusions, we argue that all DMTs are likely to benefit cognition and that, if otherwise safe, SMTs with some empirical support may be attempted at the discretion of the treating clinician. We offer some guidance on the assessment and monitoring of cognitive function to inform off-license treatment of cognitive impairment in MS patients.

Cross-cultural Adaptation, Reliability, and Validity of the BICAMS in Brazil

OBJECTIVE

To investigate the reliability and validity of a Brazilian-Portuguese adaptation of the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS).

METHOD

A Brazilian sample of 58 multiple sclerosis (MS) patients and 58 healthy controls (HC) were administered the Brazilian-Portuguese BICAMS test battery, comprising the Symbol Digit Modalities Test (SDMT), California Verbal Learning Test Second Edition (CVLT2), and the Brief Visuospatial Memory Test Revised (BVMTR). Mean differences between groups on BICAMS tests were assessed using analysis of covariance (ANCOVA), controlling for age, gender, education, anxiety, and depression. Test-retest data were obtained from 49 of the MS patients, two weeks after the initial assessment.

RESULTS

The MS patient group scored significantly lower on all BICAMS tests (CVLT2 F1,110 = 28.99, p < .001; BVMTR F1,110 = 7.77, p < .01; SDMT F1,110 = 21.09, p < .001). Mixed-factor ANCOVAs tested differences in learning curves across trials for CVLT2 and BVMTR. HCs had significantly steeper learning curves on both CVLT2 (F1,111 = 10.82, p < .01) and BVMTR (F1,110 = 7.816, p < .01). These findings support diagnostic validity of the Brazilian-Portuguese adaptation. Test-retest reliability was satisfactory for SDMT, CVLT2, and BVMTR (.86, .84, and .77, respectively).

CONCLUSION

The results suggest that this Brazilian version of the BICAMS will be a valid and reliable measure once complete normative data become available.

Stable neuropsychiatric status in multiple sclerosis: a 3-year study

Personality changes and neuropsychiatric symptoms are found in multiple sclerosis (MS), but no study has evaluated decline compared to healthy controls. This study assessed personality traits and neuropsychiatric symptoms over 3 years using the NEO Five Factor Inventory and the Neuropsychiatric Inventory. Additional metrics evaluated ambulation, manual dexterity and cognitive function. Contrary to hypothesis, patients showed no significant change in personality or neuropsychiatric status relative to controls. Patients were impaired in motor and cognitive function at baseline and follow-up, but showed only slowing in ambulation over time. The findings indicate that neuropsychiatric status is stable in MS over 3 years.

Cognitive and White Matter Tract Differences in MS and Diffuse Neuropsychiatric Systemic Lupus Erythematosus

BACKGROUND AND PURPOSE

Multiple sclerosis and neuropsychiatric systemic lupus erythematosus are autoimmune diseases with similar CNS inflammatory and neurodegenerative characteristics. Our aim was to investigate white matter tract changes and their association with cognitive function in patients with MS and those with neuropsychiatric systemic lupus erythematosus compared with healthy controls by using diffusion tensor imaging.

MATERIALS AND METHODS

Thirty patients with relapsing-remitting MS and 23 patients with neuropsychiatric systemic lupus erythematosus matched for disease severity and duration and 43 healthy controls were scanned with 3T MR imaging. The DTI was postprocessed, corrected for lesions, and analyzed with tract-based spatial statistics. Cognitive assessment included examination of processing speed; visual, auditory/verbal, and visual-spatial memory; and sustained attention and executive function. Differences were considered significant at P < .05.

RESULTS

Tract-based spatial statistics analysis revealed significantly decreased fractional anisotropy and increased mean diffusivity in patients with MS compared with healthy controls, decreased fractional anisotropy in patients with MS compared with those with neuropsychiatric systemic lupus erythematosus, and an increased mean diffusivity in patients with neuropsychiatric systemic lupus erythematosus compared with healthy controls. Patients with MS showed decreased fractional anisotropy throughout central WM pathways, including the corpus callosum and the inferior longitudinal and fronto-occipital fasciculi compared with those with neuropsychiatric systemic lupus erythematosus. Altered cognitive scores in patients with MS were significantly associated with decreased fractional anisotropy and increased mean diffusivity in all examined domains, while in patients with diffuse neuropsychiatric systemic lupus erythematosus, only decreased fractional anisotropy in the superior WM pathways showed significant association with executive function.

CONCLUSIONS

Patients with MS and neuropsychiatric systemic lupus erythematosus showed widespread WM tract alterations outside overt lesions, though more severe changes were identified in patients with MS. The WM tract changes were associated with cognitive dysfunction in all explored domains only in patients with MS.

A new perspective on proxy report: Investigating implicit processes of understanding through patient-proxy congruence

BACKGROUND

Utilizing proxy report is a common solution to gathering quality-of-life information from people who are not capable of reliably answering questionnaires, such as people with dementia. Proxy report could, however, also provide information about patients' implicit processes of understanding, which we define as automatic, schema-driven cognitive processes that allow one to have a better understanding of oneself and of one's body, make oneself known and knowable to members of the social network, and allow one to react proactively in response to cues. We investigated whether implicit processes of understanding explain some of the association between reserve and healthy lifestyle behaviors.

METHODS

We operationalized three implicit processes of understanding: (a) psychosocial understanding; (b) insight into physical disability; and (c) somatic awareness. This secondary analysis involved a cohort of multiple sclerosis patients and their caregiver informants (n = 118 pairs). Measures included a neurologist-administered Expanded Disability Status Scale, patient- and informant-completed survey measures, and a heartbeat perception test (interoception). Patient-other congruence assessed implicit processes of understanding: psychosocial understanding (neurocognitive and personality); physical-disability insight; and somatic awareness (interoception).

RESULTS

Effect sizes (ES) for the inter-correlations between the three implicit processes were small. Psychosocial understanding was associated with higher past reserve-building activities (small ES). Psychosocial understanding explained variance in healthy lifestyle behaviors over and above the variance explained by current reserve-building activities (∆R (2) = 0.04; model R Adjusted (2) = 0.18).

CONCLUSIONS

Proxy versus patient report can provide information about underlying interpretational processes related to insight. These processes are distinct from reserve, predict health outcomes, and can inform lifestyle-changing interventions.

Cognitive and patient-reported outcomes in adults with pediatric-onset multiple sclerosis

BACKGROUND

Little is known about long-term cognitive and patient-reported outcomes of pediatric-onset multiple sclerosis (POMS).

OBJECTIVE

The objective of this paper is to compare cognitive and patient-reported outcomes in adults with POMS vs. adult-onset MS (AOMS).

METHODS

We compared standardized patient-reported measures MSQOL54, MFIS, CES-D and SDMT in adult patients with MS onset prior to and after age 18, using data gathered in the Comprehensive Longitudinal Investigations in MS at Brigham and Women's Hospital (CLIMB) study.

RESULTS

Fifty-one POMS and 550 AOMS patients were compared. SDMT scores were significantly lower in POMS after adjusting for age (-7.57 (-11.72, -3.43; p < 0.001), but not after adjusting for disease duration. Estimated group difference demonstrated lower normative z scores in POMS vs. AOMS in unadjusted analysis (-0.74 (95% CI: -1.18, -0.30; p = 0.0009) and after adjusting for disease duration (-0.60; 95%CI: -1.05, -0.15; p = 0.0097). Findings were unchanged in a subset of POMS diagnosed prior to age 18. In unadjusted and adjusted analyses, no significant differences were observed in health-related quality-of-life, fatigue, depression or social support between POMS and AOMS.

CONCLUSIONS

Younger age of onset was associated with more impairment in information-processing speed in adults with POMS compared to AOMS, and remained significant when controlling for disease duration in age-normed analysis. The two groups were similar in terms of patient-reported outcomes, suggesting similar qualitative experiences of MS.

Pallidal and caudate volumes correlate with walking function in multiple sclerosis

BACKGROUND

Walking dysfunction is common in multiple sclerosis (MS). The thalamus and basal ganglia seemingly have important associations with walking performance. The contribution of these subcortical gray matter (SGM) structures for walking dysfunction is poorly understood in MS.

PURPOSE

This study examined associations among volumes of the thalamus and basal ganglia with walking outcomes in MS.

METHOD

We enrolled 61 MS patients who underwent brain MRI and completed the 6-minute walk (6MW) and timed 25-foot walk (T25FW). Volumes of the thalamus, caudate, putamen, and pallidum as well as whole-brain white matter (WM) and gray matter (GM) were calculated from 3D T1-weighted structural brain images. We examined associations using bivariate correlations (r) and partial correlations (pr) that controlled for age, MS clinical course, and whole-brain WM and GM volumes. We further performed hierarchical linear regression (HLR) for identifying the strongest SGM correlate of walking performance.

RESULTS

The 6MW and T25FW correlated significantly with volumes of the thalamus (r's=.382 & .383), caudate (r's=.388 & .416), pallidum (r's=.457 & .457), and putamen (r's=.258 & .293) in bivariate correlations. The 6MW and T25FW remained significantly correlated with caudate (pr's=.243 & .312) and pallidum (pr's=.321 & .345) volumes in partial correlations. Pallidum volume was the strongest SGM correlate of 6MW (β=.39) and T25FW (β=.40) performance in HLR.

CONCLUSION

We provide novel evidence of possible SGM structures, particularly the pallidum and perhaps caudate, as correlates of walking performance in MS.

Quantification of global cerebral atrophy in multiple sclerosis from 3T MRI using SPM: the role of misclassification errors

Purpose

We tested the validity of a freely available segmentation pipeline to measure compartmental brain volumes from 3T MRI in patients with multiple sclerosis (MS). Our primary focus was methodological to explore the effect of segmentation corrections on the clinical relevance of the output metrics.

Methods

Three-dimensional T1-weighted images were acquired to compare 61 MS patients to 30 age- and gender-matched normal controls (NC). We also tested the within patient MRI relationship to disability (eg, expanded disability status scale [EDSS] score) and cognition. Statistical parametric mapping v. 8 (SPM8)-derived gray matter (GMF), white matter (WMF), and total brain parenchyma fractions (BPF) were derived before and after correcting errors from T1 hypointense MS lesions and/or ineffective deep GM contouring.

Results

MS patients had lower GMF and BPF as compared to NC (P<.05). Cognitively impaired patients had lower BPF than cognitively preserved patients (P<.05). BPF was related to EDSS; BPF and GMF were related to disease duration (all P<.05). Errors caused bias in GMFs and WMFs but had no discernable influence on BPFs or any MRI-clinical associations.

Conclusions

We report the validity of a segmentation pipeline for the detection of MS-related brain atrophy with 3T MRI. Longitudinal studies are warranted to extend these results.

The Effect of Culture on Two Information-Processing Speed Tests

The Symbol Digit Modalities Test (SDMT) has been proposed to replace the Paced Auditory Serial Addition Test-3 (PASAT-3) in the Multiple Sclerosis Functional Composite because it has the same validity but easy and shorter administration. However, among the two tests, the one that is most affected by culture is still unknown. The purpose of this study was to compare the performance of Argentinian and North American populations on the SDMT and PASAT-3. The SDMT and PASAT-3 were administered to 137 healthy volunteers from Buffalo, NY, and 137 healthy participants from Buenos Aires, Argentina. Participants were matched by gender, age (±2), and education (±1). Significant differences were found on the SDMT but not on the PASAT-3. Significant and low correlations were found between the tests and years of education. The SDMT is more affected by culture than is the PASAT-3. Possible interpretations of this result are presented.