Benedetta Goretti

The Rao's Brief Repeatable Battery and Stroop Test: normative values with age, education and gender corrections in an Italian population.

The Brief Repeatable Battery of Neuropsychological Tests (BRB) is by far the most widely used instrument to estimate cognitive dysfunction in multiple sclerosis (MS) patients. However, the paucity of normative data currently limits its applicability. We administered the BRB to 200 healthy subjects to obtain normative values. Moreover, we assessed the influence of demographic factors on the test scores and calculated corrections for these relevant factors. To test executive functions not explored by the BRB, we also included the Stroop word-color task (ST). Higher educational level was associated with better performance on all the tests, except for the world list generation (WLG) and the ST, considering version A, and on Symbol Digit Modalities Test (SDMT), Paced Auditory Serial Addition Test (PASAT) and Selective Reminding Test-Delayed (SRT-D), considering version B. Females performed better than males on the WLG considering version A, and on the SRT-Long Term Storage (SRT-LTS) and SRT-Consistent Long Term Retrieval (SRT-CLTR) considering version B. Increasing age was associated with worse performance on the ST in version A, and on the SRT-LTS, SRT-CLTR and WLG in version B. Our data can improve the applicability of the BRB for both clinical and research purposes.

Cognitive and psychosocial features of childhood and juvenile MS

Objective: To assess the impact of multiple sclerosis (MS) on cognitive and psychosocial functioning in childhood and juvenile cases. Methods: We used an extensive neuropsychological battery assessing IQ, memory, attention/concentration, executive functions, and language. Fatigue and depression were also measured. An interview on school and daily living activities was obtained from the parents. Performance of cases was compared with that of demographically matched healthy controls. Results: Sixty-three patients and 57 healthy controls were assessed. Five patients (8%) exhibited a particularly low IQ (<70). Criteria for cognitive impairment (failure on at least three tests) were fulfilled in 19 patients (31%), whereas 32 patients (53%) failed at least two tests. Beyond deficits in memory, complex attention, and executive functions, the profile of deficits was characterized by involvement of linguistic abilities. In the regression analysis, the only significant predictor of cognitive impairment was an IQ score lower than 90 (odds ratio [OR] 18.2, 95% CI 4.6–71.7, p < 0.001). Considering the IQ score as a dependent variable, the only significant predictor was represented by younger age at onset (OR 0.7, 95% CI 0.5–0.9, p = 0.009). Depressive symptoms were reported by 6% of the cases, and fatigue was reported by 73% of the cases. MS negatively affected school and everyday activities in 56% of the subjects. Conclusions: In childhood and juvenile cases, multiple sclerosis (MS) is associated with cognitive impairment and low IQ scores, the latter related to younger age at onset. These aspects are of critical importance in helping children and adolescents with MS to manage their difficulties and psychosocial challenges.

Cognitive and psychosocial features in childhood and juvenile MS Two-year follow-up

Objective: To assess the evolution of cognitive and psychosocial functioning in a cohort of childhood and juvenile multiple sclerosis (MS) cases after a mean period of 2 years had elapsed since baseline evaluation. Methods: In this cohort study, we used the same extensive neuropsychological battery with alternative versions of the tests assessing memory, attention/concentration, executive functions, and language. Fatigue and depression were also measured. An interview on school and daily living activities was obtained from the parents. The cognitive performance of the patients was compared with that of demographically matched healthy controls (HC). Results: Fifty-six patients and 50 HC were assessed. At follow-up, criteria for cognitive impairment (failure on at least 3 tests) were fulfilled in 39 patients (70%) and 75% of the cases were classified as having a deteriorating cognitive performance. Changes were prominent in tests of verbal memory, complex attention, verbal fluency, and receptive language. In the regression analysis, the only significant predictor of cognitive deterioration was older age of the subject (odds ratio 1.9, 95% confidence interval 1.2–2.9, p = 0.003). Psychiatric disorders, most frequently depression, were diagnosed in 12 patients (30.5%). Fatigue was reported by 21% of the patients. MS negatively affected school and everyday activities in 30% to 40% of the subjects. Conclusions: Our findings confirm the importance of systematic assessment of cognitive and psychosocial issues in children and teens with MS. The progressive nature of the cognitive difficulties emphasizes the need for developing effective treatment strategies.

Cognitive impairment and its relation with disease measures in mildly disabled patients with relapsing–remitting multiple sclerosis: baseline results from the Cognitive Impairment in Multiple Sclerosis (COGIMUS) study

Background Cognitive impairment is a common symptom of multiple sclerosis (MS), but the association between cognitive impairment and magnetic resonance imaging (MRI) disease measures in patients with relapsing–remitting (RR) MS is unclear. Objectives To study the prevalence of cognitive impairment and its relation with MRI disease measures in mildly disabled patients with RRMS. Methods Patients aged 18–50 years with RRMS (McDonald criteria) and an Expanded Disability Status Scale (EDSS) score ≤4.0, who were enrolled in the Cognitive Impairment in Multiple Sclerosis (COGIMUS) study, underwent baseline standardized MRI complete neurological examination and neuropsychological testing. Results A total of 550 patients were enrolled, 327 of whom underwent MRI assessments. Cognitive impairment (impaired performance in ≥3 cognitive tests) was present in approximately 20% of all patients and in the subgroup who underwent MRI. T2 hyperintense and T1 hypointense lesion volumes were significantly higher in patients with cognitive impairment (defined as impaired performance on at least three tests of the Rao’s battery) than those without. EDSS score was also significantly higher in cognitively impaired than in cognitively preserved patients. Disease duration, depression, and years in formal education did not differ significantly between cognitively impaired and cognitively preserved patients. T2 lesion volume, performance intelligence quotient, and age were significant predictors of cognitive impairment in this population. Weak correlations were found between performance on individual cognitive tests and specific MRI measures, with T1 and T2 lesion volumes correlating with performance on most cognitive tests. Conclusions Cognitive impairment occurs in approximately one-fifth of mildly disabled patients with MS and is associated with specific MRI disease measures. Assessment of cognitive function at diagnosis could facilitate the identification of patients who may benefit from therapeutic intervention with disease-modifying therapies to prevent further lesion development.

Cognitive impairment predicts conversion to multiple sclerosis in clinically isolated syndromes

Significant cognitive impairment has been found in 20—30% of patients with clinically isolated syndromes suggestive of multiple sclerosis. In this study we aimed to assess the prognostic value of the presence of cognitive impairment for the conversion to multiple sclerosis in patients with clinically isolated syndromes. All patients with clinically isolated syndromes consecutively referred to our centre since 2002 and who had been followed-up for at least one year underwent cognitive assessment through the Rao’s Battery and the Stroop test. Possible predictors of conversion to clinically definite multiple sclerosis were evaluated through the Kaplan Meier curves and Cox regression analysis. A total of 56 patients (41 women; age 33.2 ± 8.5 years; expanded disability scale score 1.2 ± 0.7) were recruited. At baseline, 32 patients (57%) fulfilled McDonald’s criteria for dissemination in space. During the follow-up (3.5 ± 2.3 years), 26 patients (46%) converted to a diagnosis of multiple sclerosis. In particular, 64% of patients failing ≥ 2 tests and 88% of patients failing ≥ 3 tests converted to multiple sclerosis. In the Cox regression model, the failure of at least three tests (HR 3.3; 95% CI 1.4—8.1; p = 0.003) and the presence of McDonald’s dissemination in space at baseline (HR 3.8; 95% CI 1.5—9.7; p = 0.005), were found to be predictors for conversion to multiple sclerosis. We conclude that cognitive impairment is detectable in a sizable proportion of patients with clinically isolated syndromes. In these subjects cognitive impairment has a prognostic value in predicting conversion to multiple sclerosis and may therefore play a role in therapeutic decision making.

Cognitive assessment and quantitative magnetic resonance metrics can help to identify benign multiple sclerosis.

Background: The definition of benign multiple sclerosis (B-MS) is still controversial. This mainly takes into account the subject’s motor ability, with little or no relevance to other important features such as cognition. Moreover, no paraclinical markers are currently available to reliably identify patients who will remain benign in the long term. Objectives: To assess, by using quantitative magnetic resonance (MR) metrics, differences in tissue damage between B-MS patients after dividing them into two groups on the basis of their cognitive performance. Methods: Forty-seven B-MS patients (Expanded Disability Status Scale score ≤3.0 and disease duration ≥15 years) underwent neuropsychological assessment through the Rao Brief Repeatable Battery and the Stroop Test. At that time, B-MS patients underwent conventional brain MR and magnetization transfer (MT) imaging. White matter lesion load, global and regional brain volumes, and MT ratio (MTr) in lesions and normal-appearing brain were measured. Quantitative MR measures were compared in cognitively impaired (CI-MS) and cognitively preserved (CP-MS) patients and in 24 demographically matched healthy controls. Test performance was correlated with MR changes in specific cortical regions. Results: Eleven patients were classified as CI-MS, and 36 were classified as CP-MS. Both T2-weighted and T1-weighted lesion loads were higher (p = 0.05 and 0.001) in CI-MS than in CP-MS patients. Furthermore, CI-MS patients were characterized by more pronounced decrease in neocortical volume (p = 0.005) and cortical MTr (p = 0.02) values than CP-MS patients. Finally, test performance correlated significantly with MR changes in relevant cortical regions. Conclusions: Cognitive assessment and quantitative magnetic resonance can help to reliably identify benign multiple sclerosis patients.

Cognitive impairment in early stages of multiple sclerosis

Cognitive dysfunction involves 40–65% of multiple sclerosis patients and can have a great functional impact. It can be detected in all the disease phenotypes since the early stages of the disease, and tends to progress over time. Memory, complex attention, information-processing speed and executive functions are most commonly involved. The relationship between cognitive changes and magnetic resonance imaging (MRI) findings may involve changes in different areas, including white matter lesions, cortical and deep grey matter and normal appearing brain tissue on conventional MRI. The search for effective therapeutic strategies is a major undertaking, involving the use of both pharmacologic and rehabilitative approaches. Early treatment with disease-modifying drugs that can contain the disease burden in the brain seems to be highly advisable in order to prevent or delay the development of cognitive impairment.

Relevance of cognitive deterioration in early relapsing-remitting MS: a 3-year follow-up study

Objective: To assess longitudinally cognitive functioning in relapsing—remitting multiple sclerosis (RRMS) patients and its relationship with clinical and MRI variables. Methods: Early RRMS patients and matched healthy controls were assessed in parallel in three testing sessions over 3 years, using the Rao’s Brief Repeatable Battery of Neuropsychological Tests. Patients also underwent an MRI analysis of T2-weighted lesion volume (T2LV), number of gadolinium-enhanced lesions and whole brain atrophy. Forty-nine RRMS patients (mean age 36.9 ± 8.9 years; mean disease duration 2.9 ± 1.7 years, mean Expanded Disability Status Scale, 1.7 ± 0.7) and 56 healthy controls were recruited. Results: At baseline, cognitive impairment was detected in 15 patients (30.6%). After 3 years, cognitive functioning worsened in the 29.3% of patients, whereas Expanded Disability Status Scale progression was observed in only three patients. The most sensitive test to detect cognitive deterioration over time was the Symbol Digit Modalities Test (SDMT). Only the presence of moderate cognitive impairment at baseline predicted further cognitive deterioration (p = 0.03). Among MRI variables, T2LV showed a weak to moderate relationship with some cognitive tasks. Conclusions: Over a 3-year period cognitive deterioration can be expected in approximately one-third of MS patients with relatively short disease duration. The SDMT is particularly suitable for longitudinal assessment of MS-related cognitive changes.

Association of MRI metrics and cognitive impairment in radiologically isolated syndromes

Objective: To evaluate cognitive changes in a cohort of radiologically isolated syndromes (RIS) suggestive of multiple sclerosis (MS) and to assess their relationship with quantitative magnetic resonance (MR) measures such as white matter (WM), lesion loads, and cerebral atrophy. Methods: We assessed the cognitive performance in a group of 29 subjects with RIS recruited from 5 Italian MS centers and in a group of 26 patients with relapsing-remitting MS (RRMS). A subgroup of 19 subjects with RIS, 26 patients with RRMS, and 21 healthy control (HC) subjects also underwent quantitative MR assessments, which included WM T1 and T2 lesion volumes and global and cortical brain volumes. Results: Cognitive impairment of the same profile as that of RRMS was found in 27.6% of our subjects with RIS. On MR scans, we found comparable levels of lesion loads and brain atrophy in subjects with RIS and well-established RRMS. In subjects with RIS, high T1 lesion volume (ρ = 0.526, p = 0.025) and low cortical volume (ρ = −0.481, p = 0.043) were associated with worse cognitive performance. Conclusions: These findings emphasize the importance of including accurate neuropsychological testing and quantitative MR metrics in subjects with RIS suggestive of MS. They can provide a better characterization of these asymptomatic subjects, potentially useful for diagnostic and therapeutic decisions.

Cognitive reserve and cortical atrophy in multiple sclerosis A longitudinal study

Objective: To test the cognitive reserve (CR) hypothesis in the model of multiple sclerosis (MS) by assessing the interactions among CR, brain atrophy, and cognitive efficiency in patients with relapsing-remitting MS. Methods: A Cognitive Reserve Index was calculated including education, premorbid leisure activities, and IQ. Brain atrophy was assessed through magnetic resonance quantitative parameters of normalized total brain volume and normalized cortical volume. Cognitive function was measured using Raos Brief Repeatable Battery. Results: Fifty-two patients with relapsing-remitting MS were evaluated at baseline and 35 of them were reassessed after a 1.6-year follow-up period. At baseline, higher CR predicted better performance on most of the Brief Repeatable Battery tests, independent of brain atrophy and clinical and demographic characteristics (p ≤ 0.021). An interaction between CRI and normalized cortical volume predicted better cognitive performance on tasks of verbal memory and attention/information processing speed (p < 0.005). However, at the follow-up examination, progressing cortical atrophy (β = 0.45; p = 0.008) and older age (β = −0.33; p = 0.044) were the only predictors of deteriorating cognitive performance. Conclusions: Our findings suggest that higher CR in individuals with MS may mediate between cognitive performance and brain pathology. CR-related compensation may, however, fail with progression of damage. The time window of opportunity for therapeutic approaches aimed at intellectual enhancement most likely lies in the earliest disease stages.