Correction to: Aging with multiple sclerosis: prevalence and profile of cognitive impairment.

The above article was published online with an error in author name's affiliation. The Author Claudia Niccolai has changed her affiliation to IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy.

Aging with multiple sclerosis: prevalence and profile of cognitive impairment.

BACKGROUND: The increase in life expectancy of patients with multiple sclerosis (MS) requires a better knowledge of disease features in the older patients group. OBJECTIVE: To describe the prevalence and profile of cognitive impairment (CI) in older patients with MS and perform a comparison with younger patients. METHODS: Patients were consecutively recruited for 6 months. Cognitive performance was assessed through the Brief Repeatable Battery and the Stroop Test. CI was defined as impairment in ≥ 2 cognitive domains. RESULTS: We identified 111 patients older than 55 years (mean age 59.7 years). The prevalence of CI was 77.4%, which was significantly higher than in younger patients (42.8%; p < 0.01). Information processing speed was the most impaired domain (68.8%), followed by verbal learning (49.5%), executive function (47.7%), and visuospatial learning (26.6%). We found no significant differences in the prevalence of impairment in the distinct cognitive domains between older and younger patients with CI. Depression and fatigue were not associated with increased CI among patients in the older age group (p > 0.70). CONCLUSION: There is a remarkably high frequency of CI in older patients with MS. The similar profile of CI between older and younger patients suggests that CI is mostly directly related to MS itself and not to comorbid age-related disorders.

Patients with paediatric-onset multiple sclerosis are at higher risk of cognitive impairment in adulthood: An Italian collaborative study.

BACKGROUND: Patients with paediatric-onset multiple sclerosis (POMS) could be at an increased risk for cognitive impairment (CI), given the potential harmful effects of disease activity in neurodevelopment. However, there is scarce information on their long-term cognitive outcomes. OBJECTIVE: To compare the prevalence and profile of CI between adults with a history of POMS and those with classic, adult-onset multiple sclerosis (AOMS). METHODS: Cognitive performance was assessed through the Brief Repeatable Battery (BRB) and the Stroop Test in consecutive patients referred to six Italian MS centres. CI was defined as impairment in ⩾2 cognitive domains. RESULTS: In all, 119 patients with POMS and 712 with AOMS were included in this analysis. The prevalence of CI was 48.0% in AOMS, 44.5% in POMS; with similar neuropsychological profile between the two groups. However, when adjusting for current age, we found a significantly increased risk for CI (odds ratio (OR) = 1.71; p = 0.02) and for impairment in information processing speed (OR = 1.86; p < 0.01) in patients with POMS. A higher Expanded Disability Status Scale (EDSS) was also identified in POMS ( p = 0.03) compared with AOMS patients. CONCLUSION: Patients with a history of POMS appear to be at higher risk of physical and cognitive disability than AOMS patients, after correcting for age effects, with particular involvement of information processing speed.

Age and disability drive cognitive impairment in multiple sclerosis across disease subtypes.

BACKGROUND: There is limited and inconsistent information on the clinical determinants of cognitive impairment (CI) in multiple sclerosis (MS). OBJECTIVE: The aim of this study was to compare the prevalence and profile of CI across MS disease subtypes and assess its clinical determinants. METHODS: Cognitive performance was assessed through the Brief Repeatable Battery and the Stroop test in consecutive patients with MS referred to six Italian centers. CI was defined as impairment in ⩾ 2 cognitive domains. RESULTS: A total of 1040 patients were included, 167 with clinically isolated syndrome (CIS), 759 with relapsing remitting (RR), 74 with secondary progressive (SP), and 40 with primary progressive (PP) disease course. The overall prevalence of CI was 46.3%; 34.5% in CIS, 44.5% in RR, 79.4% in SP, and 91.3% in PP. The severity of impairment and the number of involved domains were significantly higher in SP and primary progressive multiple sclerosis (PPMS) than in CIS and RR. In multivariable logistic regression analysis, the presence of CI was significantly associated with higher Expanded Disability Status Scale (EDSS) and older age. CONCLUSION: CI is present in all MS subtypes since the clinical onset and its frequency is increased in the progressive forms, but these differences seem to be more associated with patient age and physical disability than to disease subtype per se.

The cognitive reserve theory in the setting of pediatric-onset multiple sclerosis.

BACKGROUND: The study of cognitive reserve (CR) in relationship with cognitive impairment (CI) in pediatric-onset multiple sclerosis (POMS) may provide cues to identifying subjects at higher risk of impairment and scope for therapeutic strategies. OBJECTIVES: To assess the potential impact of CR on cognition in a cohort of POMS patients. METHODS: In all, 48 POMS patients were followed up for 4.7 ± 0.4 years. CI was defined as the failure of ⩾3 tests on an extensive neuropsychological battery. Change of neuropsychological performance was assessed through the Reliable Change Index (RCI) method. At baseline, CR was estimated by measuring the intelligence quotient (IQ). The relationships were assessed through multivariable regression analyses. RESULTS: At baseline, CI was detected in 14/48 (29.2%) patients. Two out of 57 healthy control (HC; 3.5%) met the same criteria of CI (p < 0.001). A deteriorating cognitive performance using the RCI method was observed in 18/48 patients (37.6%). Among the 34 cases who were cognitively preserved at baseline, a higher reserve predicted stable/improving performance (odds ratio (OR) = 1.11; 95% confidence interval (CI): 1.03-1.20; p = 0.006). CONCLUSION: Our results suggest that higher CR in POMS patients may protect from CI, particularly in subjects with initial cognitive preservation, providing relevant implications for counseling and rehabilitation strategies.

A comparison of the brief international cognitive assessment for multiple sclerosis and the brief repeatable battery in multiple sclerosis patients.

BACKGROUND: Recently, a Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) has been developed as an international and standardized brief cognitive test, which is easily performed in everyday clinical practice for neuropsychological assessment in multiple sclerosis (MS). However, we need to gather more information about this tool compared to other neuropsychological batteries. The aim of our study is to compare the performance of BICAMS and Brief Repeatable Battery (BRB) in MS subjects. METHODS: Tests of the BRB and BICAMS were administered to MS patients recruited from 11 Italian MS centres. Cognitive impairment (CI) was defined as the failure on at least two tests (scores below the fifth percentile) on the BRB and as the failure on at least one test of the BICAMS. The agreement between the performances on the two batteries was assessed through Cohen's K statistic. Finally we calculated the effects sizes for each test of the two batteries using Cohen's d. RESULTS: The two batteries were administered to 192 MS patients (142 women, 50 men; mean age 41.4 ± 10.8 years, mean education 12.3 ± 3.5 years). Mean scores of patients were lower compared to those of healthy subjects in all the cognitive measures examined. Forty-six MS patients were identified as impaired and 48 as unimpaired on both of the batteries, when the Symbol Digit Modalities Test (SDMT) was included in the analysis. Cohen's K statistic was 0.46 which corresponds to a moderate accord. If the SDMT was excluded from the BRB, 37 MS patients were identified as impaired and 57 as unimpaired on both of the batteries. Cohen's K statistic was 0.3 which corresponds to a poor accord. The SDMT, the Paced Auditory Serial Addition Test (PASAT) 3 and 2 yielded higher d values (SDMT 0.83, PASAT 3 0.65, PASAT 2 0.84). CONCLUSIONS: This study confirms the feasibility of BICAMS in everyday clinical practice for the identification of CI and highlights the good psychometric properties of the SDMT.

Long-term Cognitive Outcomes and Socioprofessional Attainment in People With Multiple Sclerosis With Childhood Onset.

BACKGROUND AND OBJECTIVES: Patients with pediatric-onset multiple sclerosis (MS) can be especially vulnerable to cognitive impairment (CI) due to the onset of MS during a critical period for CNS development and maturation. The objective of this longitudinal study was to assess long-term cognitive functioning and socioprofessional attainment in the Italian pediatric MS cohort, previously assessed at baseline and 2 and 5 years. METHODS: The 48 patients evaluated at the 5-year assessment were screened for inclusion. All participants were assessed with a cognitive test battery exploring 4 different cognitive abilities. Depression, fatigue, and socioprofessional attainment were also assessed. Mean cognitive z scores were calculated for the whole cohort, and their evolution over time was analyzed with an analysis of variance for repeated measurements test. Predictors of cognitive worsening or improvement were assessed with a linear mixed-model analysis. RESULTS: Thirty-three participants were included (mean follow-up 12.8 ± 0.8 years). The global cognitive performance worsened at year 2 and improved at year 5, although the z score remained significantly lower than at baseline (-0.9 ± 1.2 vs -0.3 ± 0.9, p = 0.002). There was no significant variation between years 5 and 12 (-0.7 ± 1.1, p = 0.452). Higher IQ (>90) at baseline (effect 0.3, 95% CI 0.1-0.5, p = 0.017) and lower number of relapses in the 2 years before baseline (effect -0.1, 95% CI -0.1 to 0.1, p = 0.025) predicted better cognitive performances. Eighteen (54.5%) patients failed at least 2 tests compared with healthy controls and were defined as cognitively impaired. The presence of CI predicted worse socioprofessional attainment (ß = 4.8, 95% CI 1.4-8.2, p = 0.008). DISCUSSION: The longitudinal cognitive trajectory in pediatric-onset MS has a heterogeneous course over time, with a decline in the first years followed by a partial recovery over the long term. However, at the last follow-up evaluation, the proportion of impaired patients was more than double compared with baseline, with a negative impact on the individual's socioprofessional attainment in adulthood. This study underscores how cognitive reserve may partially mitigate the negative effects of brain damage, highlighting the critical importance of intellectual enrichment early during the disease course.

Identifying the Distinct Cognitive Phenotypes in Multiple Sclerosis.

Importance: Cognitive impairment is a common and disabling feature of multiple sclerosis (MS), but a precise characterization of cognitive phenotypes in patients with MS is lacking. Objectives: To identify cognitive phenotypes in a clinical cohort of patients with MS and to characterize their clinical and magnetic resonance imaging (MRI) features. Design, Setting, and Participants: This multicenter cross-sectional study consecutively screened clinically stable patients with MS and healthy control individuals at 8 MS centers in Italy from January 1, 2010, to October 31, 2019. Patients with MS and healthy control individuals who were not using psychoactive drugs and had no history of other neurological or medical disorders, learning disability, severe head trauma, and alcohol or drug abuse were enrolled. Main Outcomes and Measures: Participants underwent a neurological examination and a cognitive evaluation with the Rao Brief Repeatable Battery and Stroop Color and Word Test. A subgroup of participants also underwent a brain MRI examination. Latent profile analysis was used on cognitive test z scores to identify cognitive phenotypes. Linear regression and mixed-effects models were used to define clinical and MRI features of each phenotype. Results: A total of 1212 patients with MS (mean [SD] age, 41.1 [11.1] years; 784 women [64.7%]) and 196 healthy control individuals (mean [SD] age, 40.4 [8.6] years; 130 women [66.3%]) were analyzed in this study. Five cognitive phenotypes were identified: preserved cognition (n = 235 patients [19.4%]), mild-verbal memory/semantic fluency (n = 362 patients [29.9%]), mild-multidomain (n = 236 patients [19.5%]), severe-executive/attention (n = 167 patients [13.8%]), and severe-multidomain (n = 212 patients [17.5%]) involvement. Patients with preserved cognition and mild-verbal memory/semantic fluency were younger (mean [SD] age, 36.5 [9.8] years and 38.2 [11.1] years) and had shorter disease duration (mean [SD] 8.0 [7.3] years and 8.3 [7.6] years) compared with patients with mild-multidomain (mean [SD] age, 42.6 [11.2] years; mean [SD] disease duration, 12.8 [9.6] years; P < .001), severe-executive/attention (mean [SD] age, 42.9 [11.7] years; mean [SD] disease duration, 12.2 [9.5] years; P < .001), and severe-multidomain (mean [SD] age, 44.0 [11.0] years; mean [SD] disease duration, 13.3 [10.2] years; P < .001) phenotypes. Severe cognitive phenotypes prevailed in patients with progressive MS. At MRI evaluation, compared with those with preserved cognition, patients with mild-verbal memory/semantic fluency exhibited decreased mean (SE) hippocampal volume (5.42 [0.68] mL vs 5.13 [0.68] mL; P = .04), patients with the mild-multidomain phenotype had decreased mean (SE) cortical gray matter volume (687.69 [35.40] mL vs 662.59 [35.48] mL; P = .02), patients with severe-executive/attention had higher mean (SE) T2-hyperintense lesion volume (51.33 [31.15] mL vs 99.69 [34.07] mL; P = .04), and patients with the severe-multidomain phenotype had extensive brain damage, with decreased volume in all the brain structures explored, except for nucleus pallidus, amygdala and caudate nucleus. Conclusions and Relevance: This study found that by defining homogeneous and clinically meaningful phenotypes, the limitations of the traditional dichotomous classification in MS can be overcome. These phenotypes can represent a more meaningful measure of the cognitive status of patients with MS and can help define clinical disability, support clinicians in treatment choices, and tailor cognitive rehabilitation strategies.

Two Years Follow up of Domain Specific Cognitive Training in Relapsing Remitting Multiple Sclerosis: A Randomized Clinical Trial.

Cognitive rehabilitation in multiple sclerosis (MS) has been reported to induce neuropsychological improvements, but the persistence of these effects has been scarcely investigated over long follow ups. Here, the results of a multicenter randomized clinical trial are reported, in which the efficacy of 15 week domain specific cognitive training was evaluated at 2 years follow up in 41 patients. Included patients were randomly assigned either to domain specific cognitive rehabilitation, or to aspecific psychological intervention. Patients who still resulted to be cognitively impaired at 1 year follow up were resubmitted to the same treatment, whereas the recovered ones were not. Neuropsychological tests and functional scales were administered at 2 years follow up to all the patients. Results revealed that both at 1 and at 2 years follow up more patients in the aspecific group (18/19, 94% and 13/17, 76% respectively) than in the specific group (11/22, 50% and 5/15, 33% respectively) resulted to be cognitively impaired. Furthermore patients belonging to the specific group showed significantly less impaired tests compared with the aspecific group ones (p = 0.02) and a significant amelioration in the majority of the tests. On the contrary patients in the aspecific group did not change. The specific group subjects also perceived a subjective improvement in their cognitive performance, while the aspecific group patients did not. These results showed that short time domain specific cognitive rehabilitation is a useful treatment for patients with MS, shows very long lasting effects, compared to aspecific psychological interventions. Also subjective cognitive amelioration was found in patients submitted to domain specific treatment after 2 years.

Neuropsychological features in childhood and juvenile multiple sclerosis: five-year follow-up.

OBJECTIVE: The aim of the study was to perform a third cognitive assessment in our pediatric-onset multiple sclerosis (MS) patient cohort and determine predictors of the individual cognitive outcome. METHODS: After 4.7 ± 0.7 years from baseline evaluation, 48 of 63 patients in the original cohort were reassessed on an extensive neuropsychological battery and compared with 46 healthy controls. Two alternate versions of the tests were used at different assessment points. Cognitive impairment was defined as the failure of ≥3 tests; individual change in the cognitive impairment index was measured. RESULTS: At year 5, 38% of the subjects with MS fulfilled our criterion for impairment. Between years 2 and 5, regarding individual cognitive impairment index change, 66.7% of the patients improved. However, comparing baseline and 5-year testing (when the same versions of the tests were used), cognitive impairment index deterioration was observed in 56% of the patients, improvement in 25%, and stability in 18.8%. A deteriorating performance was related to male sex, younger age and age at MS onset, and lower education. None of these variables, however, was retained in the multivariate analysis. CONCLUSIONS: Cognitive outcome in pediatric-onset MS can be heterogeneous. Progression of cognitive problems in a few subjects and potential for compensation and improvement in others call for systematic cognitive screening in this population and development of effective treatment strategies.