Carolina de Medeiros Rimkus1, Isabella Maria Bello Avolio2, Eliane Correa Miotto3, Samira Apostolos Pereira4, Maria Fernanda Mendes5, Dagoberto Callegaro6, Claudia da Costa Leite7. 1. Department of Radiology and Oncology, Laboratory of Medical Investigation (LIM-44), Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, Brazil. Electronic address: carolina.rimkus@usp.br. 2. Department of Neurology, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, SP, Brazil. Electronic address: Isabellaavolio335@gmail.com. 3. Department of Neurology, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, SP, Brazil. Electronic address: ecmiotto@usp.br. 4. Department of Neurology, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, SP, Brazil. Electronic address: samira.apostolos.neuro@gmail.com. 5. Department of Neurology, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, SP, Brazil. Electronic address: dra.mfmendes@gmail.com. 6. Department of Neurology, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, SP, Brazil. Electronic address: dgcallegaro@yahoo.com. 7. Department of Radiology and Oncology, Laboratory of Medical Investigation (LIM-44), Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, Brazil. Electronic address: claudia.leite@hc.fm.usp.br.
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.
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 MSpatients 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 MSpatients 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 impairedpatients was observed in MSpatients 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 MSpatients 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 MSpatients. 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.
Authors: Andreas Johnen; Paul-Christian Bürkner; Nils C Landmeyer; Björn Ambrosius; Pasquale Calabrese; Jeremias Motte; Nicole Hessler; Gisela Antony; Inke R König; Luisa Klotz; Muna-Miriam Hoshi; Lilian Aly; Sergiu Groppa; Felix Luessi; Friedemann Paul; Björn Tackenberg; Florian Then Bergh; Tania Kümpfel; Hayrettin Tumani; Martin Stangel; Frank Weber; Antonios Bayas; Brigitte Wildemann; Christoph Heesen; Uwe K Zettl; Frauke Zipp; Bernhard Hemmer; Sven G Meuth; Ralf Gold; Heinz Wiendl; Anke Salmen Journal: J Neurol Date: 2018-12-04 Impact factor: 4.849