Volume 5 • Issue 2 • 1000220 J Mult Scler (Foster City), an open access journal ISSN: 2376-0389 Drakulic et al., J Mult Scler (Foster City) 2018, 5:2 DOI: 10.4172/2376-0389.1000220 Research Article Open Access J o u r n a l o f M u lti p l e S c l e r o s i s ISSN: 2376-0389 Journal of Multiple Sclerosis *Corresponding author: Aleksic DZ, Department of neurology, Faculty of Medical Sciences, University of Kragujevac, Serbia, Tel: 381642287184; E-mail: drdeal1987@gmail.com Received May 13, 2018; Accepted June 12, 2018; Published June 19, 2018 Citation: Drakulic SM, Vujic A, Arsic AA, Lazarevic S, Jevdjic J, et al. (2018) Event Related Brain Potentials (ERP) Could Not Assess the Risk of Cognitive Impairment in Relapse-Remitting Multiple Sclerosis (RRMS). J Mult Scler (Foster City) 5: 220. doi: 10.4172/2376-0389.1000220 Copyright: © 2018 Drakulic SM, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited Keywords: Event related brain potentials; Cognitive impairment; Multiple sclerosis; PASAT; SDMT; INFβ Introduction Cognitive problems in patients with multiple sclerosis (MS) occur widely in up to 62% of cases, especially concerning executive functions, processing speed, attention, short-term memory and verbal fuency [1]. Te use of disease modifying therapies (DMTs), such as interferon beta-1a (INFβ-1a) and interferon beta-1b (INFβ-1b) is considered to afect the cognitive performance of patients with relapsing- remitting multiple sclerosis (RRMS) [2-4], although there are opposite opinions [5]. Cognitive assessment is performed using a battery of neuropsychological tests, such as the Paced Auditory Serial Addition Test 3 (PASAT-3) [6], and Symbol Digit Modalities Test (SDMT) [7-11]. In some studies with a small number of patients, p300 event-related brain potentials (ERP) are considered to be an indicator of objective neuropsychological cognitive functioning for measuring cognitive function in patients with MS [12]. Te frst objective of our study was to determine whether there are diferences between groups of patients receiving therapy, patients without therapy and a control group, in terms of neuropsychological test results and ERP. Te second objective was to determine factors that may serve to assess the risk of cognitive impairment in patients with RRMS. Materials and Methods Participants In the period from 01.05.2016 to 01.07.2016 in the Department of Neurology of the Clinical Center Kragujevac and the Faculty of medical Sciences, University of Kragujevac, Kragujevac, Serbia, we examined a total of 81 patients with RRMS (71.7%) and 32 healthy controls (28.3%). We tested all patients from our center with RRMS who were on DMTs. Te aims of our study were explained to them and informed consent was signed by all participants and approved by the Ethics Committee of the Clinical Center, Kragujevac. Diagnosis of defnitive RRMS was made using the 2010 revisions to the McDonald criteria [13]. All patients fulflled the inclusion criteria, i.e. they had RRMS without disability in a functional system that would prevent testing. Te exclusion criteria for the group of patients were presence of other neurological diseases and psychiatric disorders, use of neuroleptics, anticholinergics, antidepressants and antiepileptic drugs, relapse and use of corticosteroid therapy in the last month before the tests. Te inclusion criteria for the control group were absence of: neurological disease, psychiatric diagnoses, use of any drugs. Te RRMS group and the control group were matched by age, gender and education. Patients were divided into three subgroups: those who were not receiving DMTs, patients on INF β-1a and patients on INFβ-1b. Some patients were not receiving DMTs for economic (fnancial) reasons in Serbia. Tey had not been given other types of DMTs earlier. Event Related Brain Potentials (ERP) Could Not Assess the Risk of Cognitive Impairment in Relapse-Remitting Multiple Sclerosis (RRMS) Svetlana Miletic Drakulic 1 , Ana Vujic 2 , Ana Azanjac Arsic 1 , Snezana Lazarevic 1 , Jasna Jevdjic 3 , Dejan Z. Aleksic 1 * 1 Department of neurology, Faculty of Medical Sciences, University of Kragujevac, Serbia 2 Department of Pediatrics, Faculty of Medical Sciences, University of Kragujevac, Serbia 3 Department of Surgery, Faculty of Medical Sciences, University of Kragujevac, Serbia Abstract Objectives: The frst objective of our study was to determine differences between groups of patients receiving disease modifying therapy (DMTs) (INFβ-1a and INFβ-1b), patients without DMTs and a control group, in terms of neuropsychological tests and event-related brain potentials (ERP). The second objective was to determine factors that may serve to assess the risk of cognitive impairment in patients with relapsing remitting multiple sclerosis (RRMS). Methods: A total of 81 RRMS patients (mean age 41.09 ± 8.71 years old, 51 women, mean disease duration 133.05 ± 76.56 months) and 32 healthy controls participated in the study. Cognitive functions were evaluated using a standard PASAT-3, the symbol digit modality test (SDMT) and ERP. Results: There were statistically signifcant differences between the mean values for parietal (Pz) (p ≤ 0.05) and central (Cz) latency (p<0.05) between the four groups of study participants. RRMS increased the risk of cognitive impairment approximately 3.5 fold. Each year of age raised the risk of cognitive impairment by 6.0%. Each unit increase in level of education reduced the risk of cognitive impairment approximately 2.5 fold. Increase in reaction time (RT) Cz by 1 ms elevated the risk of cognitive impairment by 0.5%. Conclusions: There were statistically signifcant differences between the mean values of Pz and Cz latency between the four groups of study participants. Factors that may be used to assess the risk of developing cognitive impairment in patients with RRMS include age, education level, and RT Cz. However, ERP (latency and amplitude) did not independently assess the risk of cognitive impairment in RRMS patients.