Auditory Test of Processing Speed: Preliminary validation of a smartphone-based test of mental speed.

BACKGROUND: The Symbol Digit Modalities Test (SDMT) is a gold-standard measure of cognitive efficiency and processing speed for people with multiple sclerosis (PwMS) but relies on vision and oculomotor function. OBJECTIVES: To develop and validate a new processing speed test with minimal memory involvement and no eye function requirements. METHODS: We created an Auditory Test of Processing Speed (ATOPS). A total of 122 PwMS, of whom 33 were severely disabled (median Expanded Disability Status Scale 8.0) and 37 healthy volunteers (HVs), were enrolled. We assessed sensitivity to discriminate MS participants from HVs, convergent validity between ATOPS and SDMT, sensitivity to discriminate between cognitively impaired (CI) and cognitively preserved (CP) MS participants, and correlations with MS pathology (overall brain lesion burden). Acceptability was examined with completion rates and participant ratings of ATOPS. RESULTS: ATOPS discriminated PwMS from HVs (d = 0.739-0.856), correlated with SDMT (|r| = 0.528-0.587), discriminated between CI and CP PwMS (d = 0.623-0.776), and correlated with lesion burden (r = 0.332-0.436). All groups indicated high favorability of ATOPS and severely disabled MS patients could be assessed by ATOPS more frequently than by SDMT (100% vs. 72.4% completion). CONCLUSIONS: ATOPS is a novel, accessible, and acceptable cognitive processing speed test that may be useful in clinical and/or research settings.

Detecting isolated cognitive relapses in persons with MS.

BACKGROUND: The existence of isolated cognitive relapses (ICRs) in persons with MS (PwMS) has been debated. OBJECTIVE: To examine relapses with decline on Symbol Digit Modalities Test (SDMT) but no change on Expanded Disability Status Scale (EDSS). METHODS: This 3-year prospective cohort study identified PwMS experiencing a relapse with decrease on SDMT. Participants with SDMT decline/stable EDSS were labeled "ICR," while those with a corresponding decrease on EDSS were classified "Relapse with Cognitive Decline (RCD)." Two definitions of SDMT decline were explored: (1) ⩾ 8 points, and (2) ⩾ 4 points. Logistic regression was used to analyze the relationship between ICR and RCD. RESULTS: The full cohort had 592 participants: 83 experienced relapses; 22 (26.5%) had an SDMT decrease of ⩾ 8 points; 14 (63.6%) met ICR criteria. Logistic regression (X2(1) = 5.112, p = 0.024) using demographics and disease characteristics explained 28.4% of the variance in ICR versus RCD. Only the MS Neuropsychological Questionnaire was associated with ICR (odds ratio (OR): 8.6; 95% confidence interval (CI): 1.1-16.4) 40 relapsing participants with SDMT decrease of ⩾ 4 points were identified: 26 (65%) had a stable EDSS (ICR). Logistic regression did not find any variable predictive of ICR. CONCLUSION: This prospective study demonstrates evidence of ICR in PwMS.

Predicting employment deterioration with the Processing Speed Test (PST) and SDMT in multiple sclerosis.

BACKGROUND: Employment deterioration is common in people with multiple sclerosis (PwMS). Clinicians often learn of job loss after its occurrence, leaving no opportunity for preventive measures. OBJECTIVES: Identify which neuropsychological measures discriminate between healthy volunteers (HVs) and employed/disabled PwMS at baseline and predict work deterioration over 2 years. METHODS: We examined 198 PwMS with computerized tests such as the Processing Speed Test (PST) and conventional tests such as the Symbol-Digit Modalities Test (SDMT), administered at baseline. Employment was assessed via Buffalo Vocational Monitoring Survey. Univariate and regression analyses identified significant predictors of PwMS categorized as work-stable versus work-deteriorated status. RESULTS: PwMS were impaired on all baseline assessments relative to HVs (p's < 0.001). Post hoc analyses showed that employed PwMS and HVs performed similarly and better than work-disabled PwMS. At the univariate level, both PST and SDMT discriminated between work-deteriorated and work-stable PwMS (p's < 0.01). The logistic regression model accounting for all measures retained PST and the computerized Walking Speed Test. PwMS with increased negative work events had lower PST (p < 0.001), SDMT (p < 0.001), and BVMT-R (p < 0.01) scores than stable PwMS. The related regression model retained PST and BVMT-R (p < 0.001). CONCLUSION: Cognition, as measured by the PST and BVMT-R, are predictive of job deterioration in PwMS and may be a useful screening tool to identify those at high risk of unemployment.

Repeated forms, testing intervals, and SDMT performance in a large multiple sclerosis dataset.

BACKGROUND: The Symbol Digit Modalities Test (SDMT), the most reliable and sensitive measure of cognition in people with multiple sclerosis (PwMS), is increasingly used in clinical trials and care. OBJECTIVES: We aimed to establish how SDMT performance is influenced by repeating forms and frequency of use in PwMS. METHODS: A retrospective analysis was completed on a large database of PwMS (n = 740) with multiple SDMT administrations. Change in SDMT performance was analyzed, accounting for frequency of tests and utilization of alternate- versus same-form conditions. RESULTS: SDMT administrations ranged from 2 to 14 per subject over a mean (SD) of 5.9 (4.5) years. Accounting for demographics, the mixed effects model revealed a significant main effect of SDMT exposures (1.8 point improvement per repetition, p = 0.001) and an interaction between time since previous SDMT and whether the same test form was administered in the previous administration (estimate=-1.1, p = 0.037). As well, SDMT decline is observed when testing intervals exceed two years (F = 9.69, p<0.001). CONCLUSION: Improvements in SDMT performance with repeated exposure, likely reflecting practice effects, were greatest when repeating the same SDMT form over briefer intervals. We recommend the use of alternate forms or analogous versions of timed symbol-digit coding particularly where samples are saturated with many administrations.

Preliminary Support of a Behavioral Intervention for Trait Conscientiousness in Multiple Sclerosis.

Background: Conscientiousness, or the proclivity for deliberation, achievement, and order, declines in many individuals with multiple sclerosis (MS). Decreased conscientiousness predicts future cognitive deterioration, brain atrophy, and employment loss in individuals with MS. As a psychological trait, it may be an actionable antecedent to these important outcomes. We pilot tested an application (app)-facilitated behavioral intervention to help adaptation to low conscientiousness and, in turn, improve employment. Methods: Eleven individuals with MS (5 treatment, 6 control) with low conscientiousness were recruited for a 12-week randomized controlled trial. The treatment group received a newly developed behavioral treatment and smartphone app designed to help people behave more conscientiously, 2 teleconference booster sessions, and weekly telephone calls to monitor progress. Employment changes were recorded at baseline and follow-up. Patients provided detailed posttreatment interviews. Results: Participant groups were matched on baseline age, sex, education, disease duration, hours worked, and conscientiousness. All participants in the treatment arm reported benefits, found the app easy to use, and would recommend it to others. The treatment group reported significantly more positive work outcomes relative to controls at follow-up (P = .028). Other positive life changes were described by treatment participants during post-treatment interviews. Conclusions: These results support the hypothesis that behaviors typically associated with low conscientiousness may be addressed by behavioral therapy in the MS population. In addition to the positive employment changes in the treatment group, several other quality of life changes were described by study participants. Additional research is needed.

Benchmarks of meaningful improvement on neurocognitive tests in multiple sclerosis.

BACKGROUND: Previous studies have established benchmarks of clinically meaningful decline on neuropsychological tests. However, little is known about meaningful testing benchmarks based on gains in function. OBJECTIVE: Investigate neuropsychological changes in multiple sclerosis (MS) patients with work gains and calculate benchmarks of meaningful improvement on neuropsychological tests. METHODS: A total of 323 people with MS were monitored longitudinally with neuropsychological testing and the Buffalo Vocational Monitoring Survey. RESULTS/CONCLUSIONS: Those with work gains showed significant improvement (~3 points) on the Symbol Digit Modalities Test (SDMT) over time, p = 0.01. Benchmarks for clinically meaningful improvement on the SDMT are similar to those previously established for clinically meaningful decline.

Conscientiousness and deterioration in employment status in multiple sclerosis over 3 years.

BACKGROUND: Physical and cognitive symptoms of multiple sclerosis (MS) correlate with unemployment cross-sectionally. Prospective studies, rarely published, have not accounted for personality traits such as Conscientiousness. METHODS: In a 3-year study of 70 people with MS (PwMS) and 25 healthy controls (HCs), we evaluated employment status using online interviews capturing hours worked, negative work events, employee relations, and accommodations. Deteriorating employment status (DES) was defined as reduced employment (full-time to part-time or negative work events). In PwMS, we explored workplace accommodations, disclosure of disease status, and physical/psychological predictors of DES (e.g. Conscientiousness). RESULTS: At follow-up, DES was 0% in HCs and 25.7% in MS, and 62.7% of work-stable PwMS used at least one work accommodation, most frequently, flexible hours. At baseline, DES-PwMS had lower education (p = 0.009), lower Conscientiousness (p < 0.001), more fatigue (p = 0.033), and performed worse on Symbol Digit Modalities Test (p = 0.013), Brief Visuospatial Memory Test-Revised (p = 0.041), and Nine-Hole Peg Test (p = 0.046) relative to work-stable. The model predicting DES was significant (χ2(7) = 30.936, p < 0.001) and baseline Conscientiousness accounted for more variance in DES (p = 0.004) than other factors. Higher Conscientiousness PwMS were more likely to disclose their condition at work (p = 0.038). CONCLUSION: Accommodations for low Conscientiousness, flexible hours, and physical/cognitive rehabilitation may prevent DES.

Differential Diagnosis of Cognitive Decline in Elderly Individuals With Multiple Sclerosis.

Due to increasingly improved disability outcomes, and the resultant significantly improved life span, of the multiple sclerosis (MS) population, questions regarding cognitive aging and the prevalence of comorbid Alzheimer disease (AD) have emerged. We describe neuropsychological and MRI-based changes that occurred in an 84-year-old MS patient with comorbid amnestic mild cognitive impairment (a precursor to AD) and cerebrovascular pathology. The neuropsychological examination demonstrated impairment in cognitive processing speed as well as in verbal and visual memory-domains that are potentially affected by any, or all, of the three co-existing diseases. Amyloid-based PET imaging showed increased focal uptake within the gray matter of the occipital lobe. We highlight how these clinical and radiologic observations can inform future research that could elucidate interactions between MS, a probable AD diagnosis, and cerebrovascular pathology in elderly individuals with MS. A comprehensive neuropsychological examination of multiple cognitive domains of individuals with MS may aid in the differential diagnosis of late-in-life cognitive decline.

Computerized neuropsychological assessment devices in multiple sclerosis: A systematic review.

BACKGROUND: The proliferation of computerized neuropsychological assessment devices (CNADs) for screening and monitoring cognitive impairment is increasing exponentially. Previous reviews of computerized tests for multiple sclerosis (MS) were primarily qualitative and did not rigorously compare CNADs on psychometric properties. OBJECTIVE: We aimed to systematically review the literature on the use of CNADs in MS and identify test batteries and single tests with good evidence for reliability and validity. METHOD: A search of four major online databases was conducted for publications related to computerized testing and MS. Test-retest reliability and validity coefficients and effect sizes were recorded for each CNAD test, along with administration characteristics. RESULTS: We identified 11 batteries and 33 individual tests from 120 peer-reviewed articles meeting the inclusion criteria. CNADs with the strongest psychometric support include the CogState Brief Battery, Cognitive Drug Research Battery, NeuroTrax, CNS-Vital Signs, and computer-based administrations of the Symbol Digit Modalities Test. CONCLUSION: We identified several CNADs that are valid to screen for MS-related cognitive impairment, or to supplement full, conventional neuropsychological assessment. The necessity of testing with a technician, and in a controlled clinic/laboratory environment, remains uncertain.

Cognitive Profiles of Aging in Multiple Sclerosis.

BACKGROUND: Increasingly favorable mortality prognosis in multiple sclerosis (MS) raises questions regarding MS-specific cognitive aging and the presence of comorbidities such as Alzheimer's disease (AD). OBJECTIVE: To assess elderly with MS (EwMS) and age-matched healthy controls (HCs) using both MS- and AD-specific psychometrics. METHODS: EwMS (n = 104) and 56 HCs were assessed on a broad spectrum of language, visual-spatial processing, memory, processing speed, and executive function tests. Using logistic regression analysis, we examined cognitive performance differences between the EwMS and HC groups. Cognitive impairment (CI) was defined using a -1.5 SD threshold relative to age and education years-matched HCs, in two cognitive domains. RESULTS: CI was observed in 47.1% of EwMS with differences most often seen on tests emphasizing cognitive processing speed as measured by Symbol Digit Modalities Test (SDMT) (d = 0.9, p < 0.001) and verbal fluency (both category-based d = 0.87, p < 0.001; letter-based d = 0.67, p < 0.001). After adjusting for age, sex and years of education, MS/HC diagnosis was best predicted (R 2 = 0.27) by differences in category-based verbal fluency (Wald = 9.935, p = 0.002) and SDMT (Wald = 13.937, p < 0.001). CONCLUSION: This study confirms the common hallmark of slowed cognitive processing speed in MS among elderly patients. Defective verbal fluency, less often observed in younger cohorts, may represent emerging cognitive pathology due to other etiologies.