The Hungarian validation of the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) battery and the correlation of cognitive impairment with fatigue and quality of life.

BACKGROUND Multiple Sclerosis (MS) causes not only somatic, but also cognitive impairment regardless of the patients׳ age or the course of the disease. The Brief International Cognitive Assessment for MS (BICAMS) test, published in 2011, is a short cognitive questionnaire: a fast, reliable, sensitive and specific tool for the evaluation of the patients׳ cognitive state. OBJECTIVES Our primary objective was to assess the validity of the Hungarian version of the BICAMS test. Our secondary objective was to evaluate the impact of the cognitive impairment on the patient׳s quality of life and fatigue׳s impact on the patients׳ cognitive state. METHODS 65 RR-MS patients and 65 age, sex and education matched healthy control (HC) subjects completed the test and were retested after 3 weeks. The patients also completed the MS Quality of Life 54 (MSQoL54) and the Fatigue Impact Scale (FIS) assessments. Group differences were calculated by paired sample T-tests. The test-retest reliability was measured by intraclass correlation coefficients. To analyze the difference between the test-retest performances of the two groups we used two-way repeated measures ANOVA where the BICAMS battery was the single composite outcome and one-way repeated measures ANOVA. To assess the impact of the cognitive decline on the patients׳ quality of life and fatigue׳s impact on the cognitive state, we examined the correlations between results in the BICAMS and the MSQoL54 and FIS. RESULTS We found significant difference (p ≤ 0.001, p = 0.017 in the first CVLT-II assessment) between MS patients and members of the HC group in all four evaluated parameters of BICAMS test in both sessions. The correlation coefficients were very strong between the tests and retests (r > 0.8; p < 0.001; r = 0.678, p < 0.001 between the CVLT-II assessments). We found that the HC group performed significantly (p = 0.020) better in the retest sessions as compared to their original performance than the patients did and this difference is solely due to the difference between the CVLT-II performances. We have found significant negative correlation between the patients׳ cognitive function and the fatigue score (r < -0.3, p < 0.05). Seven of the MSQoL-54 subscales correlated with the BICAMS performance (r > 0.3; < 0 .05). CONCLUSIONS The Hungarian version of the BICAMS test is a valid and reliable method for the evaluation of MS patients׳ cognitive function. It seems that because of the short retest period, the members of the HC group remembered the CVLT-II words thus performed better than the patients did. Also apparently fatigue can have a negative impact on the patients׳ cognitive state, and cognitive impairment could worsen the patients׳ quality of life.