Highlights
- •Cognitive impairment is more frequent MS patients with lower education levels.
- •Cognitive reserve has a protective effect in patients with less than 5 years of disease.
- •After 5 years, there is a stronger association between cognition and lesion burden.
Abstract
Background
Low-education attainment is associated with worse cognitive performance in multiple
sclerosis (MS) patients, and possibly with a lower cognitive reserve and/or increased
inflammatory activity. Cognitive reserve refers to the capability of a source of intellectual
enrichment in attenuating a negative effect of a disease-related factor; while the
inflammatory activity is often related to T2-lesion load (T2-LL) increase.
Objective
To disentangle the effects of cognitive reserve and an increased T2-LL in MS-patients
with low-education levels.
Methods
The study included 136 MS patients and 65 healthy-controls, divided in low-education
(12 years or less of school education without obtaining any technical superior degree)
and high-education (more than 12 years of school education with technical or superior
degree) groups. An extensive battery of neuropsychological tests was applied examining
intelligence quotient and six cognitive domains. Test results were z-scored and subjects
with z-scores ≤ −1.5 in two or more domains were considered cognitively impaired.
To test the factors associated with worse cognitive performance, regression models
were applied using average cognition as target; education level, Expanded Disability
Status Scale (EDSS), T2-LL, disease duration, age of disease onset, age and gender
as predictors. We also tested the correlation between T2-LL and cognition in the groups.
To investigate the role of education level as a source of intellectual enrichment/cognitive
reserve in different stages of MS, we sub-divided the MS patients in three groups
according to the disease duration (less than 5 years, between 5 and 10 years and more
than 10 years).
Results
Worse average cognition was associated with low-education level, higher T2-LL and
male gender. A higher frequency of cognitively impaired patients was observed in MS
patients with low-education level, in all stages of the disease. In patients with
a disease duration shorter than five years, there was a lower correlation between
worse average cognition and T2-LL in the high-education level group, compared to the
patients with low-education level; in MS patients with longer disease duration, we
observed a stronger correlation between lesion burden and cognitive impairment in
both groups.
Conclusion
Education attainment is a source of intellectual enrichment and can enhance the cognitive
reserve in MS patients. The protective effect of a high-education level was stronger
in patients with less than five years of disease, suggesting a stronger role of cognitive
reserve in short-term disease. In long-term disease we observed a greater impact of
increased inflammatory activity on cognition.
Keywords
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References
- Global Adult Tobacco Survey data as a tool to monitor the WHO Framework Convention on Tobacco Control (WHO FCTC) implementation: the Brazilian case.Int J. Environ. Res Public Health. 2012; 9: 2520-2536
- Cognitive reserve moderates decline in information processing speed in multiple sclerosis patients.J. Int Neuropsychol. Soc. 2010; 16: 829-835
- Brief Visuospatial Memory Test.Psychological Assessment Resource, Odessa1997
- Cognitive reserve moderates decline in information processing speed in multiple sclerosis patients.J. Int. Neuropsychol. Soc.: JINS. 2010; 16: 829
- Level of education and multiple sclerosis risk after adjustment for known risk factors: the EnvIMS study.Mult. Scler. J. 2015; 22: 104-111
- Varieties of anger and the inverse link between education and inflammation: toward an integrative framework.Psychosom. Med. 2013; 75: 566-574
- Hopkins Verbal Learning Test - revised.Psychological Assessment Resource, Odessa2001
- Treatment adherence in multiple sclerosis: association with emotional status, personality, and cognition.J. Behav. Med. 2010; 33: 219-227
- Age, education, and changes in the Mini-Mental State Exam scores of older women: findings from the Nun Study.J. Am. Geriatr. Soc. 1996; 44: 675-681
- Late-onset multiple sclerosis presenting with cognitive dysfunction and severe cortical/infratentorial atrophy.Mult. Scler. 2015; 21: 580-589
- Education and decline in cognitive performance: compensatory but not protective.Int J. Geriatr. Psychiatry. 1997; 12: 323-330
- Self-reported levels of education and disability progression in multiple sclerosis.Acta Neurol. Scand. 2016; 134: 414-419
- Sub-threshold cognitive impairment in multiple sclerosis: the association with cognitive reserve.J. Neurol. 2013; 260: 2256-2261
- Association of socioeconomic status with inflammatory markers: a two cohort comparison.Prev. Med. 2015; 71: 12-19
- Modifiable environmental factors in multiple sclerosis.Arq. Neuropsiquiatr. 2014; 72: 889-894
- Basal serum levels and reactivity of nerve growth factor and brain-derived neurotrophic factor to standardized acute exercise in multiple sclerosis and controls.J. Neuroimmunol. 2003; 138: 99-105
- Mayo older americans normative studies: factor analysis of an expanded neuropsychological battery.Clin. Neuropsychol. 2009; 23: 7-20
- Association of inflammatory markers with socioeconomic status.J. Gerontol. A Biol. Sci. Med Sci. 2006; 61: 284-290
- Acute axonal damage in multiple sclerosis is most extensive in early disease stages and decreases over time.Brain. 2002; 125: 2202-2212
- Recommendations for a Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS).Mult. Scler. 2012; 18: 891-898
- Brain atrophy and lesion load as explaining parameters for cognitive impairment in multiple sclerosis.Mult. Scler. 2005; 11: 524-531
- The association between cognitive impairment and physical disability in multiple sclerosis.Mult. Scler. 2005; 11: 469-476
- Cognitive reserve in multiple sclerosis: Protective effects of education.Mult. Scler. 2015; 21: 1312-1321
- Hopkins verbal learning test-revised and brief visuospatial memory test-revised: preliminary normative data for the Brazilian population.Arq. Neuropsiquiatr. 2012; 70: 962-965
- Independent effects of income and education on the risk of obesity in the Brazilian adult population.J. Nutr. 2001; 131: 881S-886S
- Effects of education level and employment status on HRQoL in early relapsing-remitting multiple sclerosis.Mult. Scler. 2007; 13: 783-791
- Higher education moderates the effect of T2 lesion load and third ventricle width on cognition in multiple sclerosis.PLoS One. 2014; 9: e87567
- An automated tool for detection of FLAIR-hyperintense white-matter lesions in Multiple Sclerosis.Neuroimage. 2012; 59: 3774-3783
- Subcortical atrophy and cognition: sex effects in multiple sclerosis.Neurology. 2012; 79: 1754-1761
- Sex-specific extent and severity of white matter damage in multiple sclerosis: implications for cognitive decline.Hum. Brain Mapp. 2014; 35: 2348-2358
- Symbol Digit Modalities Test: Manual.Western Psychological Services, Los Angeles, CA1991
- Education, survival, and independence in elderly Catholic sisters, 1936–1988.Am. J. Epidemiol. 1989; 130: 999-1012
- (ed)A compendium of Neuropsychological tests. 2nd ed. Oxford University Press, New York1998
- What is cognitive reserve? Theory and research application of the reserve concept.J. Int Neuropsychol. Soc. 2002; 8: 448-460
- Cognitive reserve.Neuropsychologia. 2009; 47: 2015-2028
- Brain networks associated with cognitive reserve in healthy young and old adults.Cereb. Cortex. 2005; 15: 394-402
- (ed)A compendium of neuropsychological tests. Administration, norms and commentary. 3rd ed. Oxford University Press, New York2006
- Sensitivity of conventional memory tests in multiple sclerosis: comparing the Rao Brief Repeatable Neuropsychological Battery and the Minimal Assessment of Cognitive Function in MS.Mult. Scler. 2009; 15: 1077-1084
- Cognitive Reserve as a Useful Concept for Early Intervention Research in Multiple Sclerosis.Front Neurol. 2015; 6: 176
- Cognitive reserve moderates the negative effect of brain atrophy on cognitive efficiency in multiple sclerosis.J. Int Neuropsychol. Soc. 2009; 15: 606-612
- Brain reserve and cognitive reserve protect against cognitive decline over 4.5 years in MS.Neurology. 2014; 82: 1776-1783
- Reading, writing, and reserve: literacy activities are linked to hippocampal volume and memory in multiple sclerosis.Mult. Scler. 2016; 22: 1621-1625
- Intellectual enrichment lessens the effect of brain atrophy on learning and memory in multiple sclerosis.Neurology. 2010; 74: 1942-1945
- Intellectual enrichment is linked to cerebral efficiency in multiple sclerosis: functional magnetic resonance imaging evidence for cognitive reserve.Brain. 2010; 133: 362-374
- Premorbid cognitive leisure independently contributes to cognitive reserve in multiple sclerosis.Neurology. 2010; 75: 1428-1431
- Normative data stratified by age and education for two measures of verbal fluency: FAS and animal naming.Arch. Clin. Neuropsychol. 1999; 14: 167-177
- The Symbol Digit Modalities Test as sentinel test for cognitive impairment in multiple sclerosis.Eur. J. Neurol. 2014; 21 (e1271-1212): 1219-1225
- WAIS-III: escala de Inteligência Wechsler para adultos: manual de administração e avaliação.Casa do Psicólogo, 2014
- Magnetic resonance imaging characteristics of children and adults with paediatric-onset multiple sclerosis.Brain. 2009; 132: 3392-3400
- Brazilian preliminary norms and investigation of age and education effects on the Modified Wisconsin Card Sorting Test, Stroop Color and Word test and Digit Span test in adults.Dement Neuropsychol. 2015; 9: 120-127
Article info
Publication history
Published online: March 06, 2018
Accepted:
March 1,
2018
Received in revised form:
February 15,
2018
Received:
August 4,
2017
Identification
Copyright
© 2018 Elsevier B.V. All rights reserved.
