P005 - Progression from radiologically isolated syndrome to multiple sclerosis

Abstract

Background The aim of this study was to estimate the progression rate from radiologically isolated syndrome (RIS) to clinically definite multiple sclerosis (MS). Methods During the mean (SD) follow-up period of 17.4 (5.4) (range 8–29) months, 25 subjects with RIS and without neurological symptom aged 22–45 years have been examined for the occurrence of clinically definite MS. The mean (SD) age of participants was 35.1 (6.2) years at first brain MRI. The criteria for definite MS were based on the revised McDonald's criteria (2010). Results Six among 25 patients developed clinical symptom consistent with criteria for definite MS. The progression rate from RIS to definite MS was 1.5 (95% confidence interval (CI) 0.54, 3.17) per 100 person-months based on 480 person-months of follow-up. Multivariate analysis revealed that the presence of contrast-enhancing lesions on the initial MRI was marginally significantly associated with MS (hazard ratio 1.83, 95% CI 0.98, 3.45, p=0.060). Conclusions This is the first estimate of progression rate from RIS to definite MS in Iran. The progression rates from RIS to definite MS in these participants are high and intensive follow-up and intervention strategies are recommended for these high risk individuals. A larger study is warranted to assess this risk in greater detail. The aim of this study was to estimate the progression rate from radiologically isolated syndrome (RIS) to clinically definite multiple sclerosis (MS). During the mean (SD) follow-up period of 17.4 (5.4) (range 8–29) months, 25 subjects with RIS and without neurological symptom aged 22–45 years have been examined for the occurrence of clinically definite MS. The mean (SD) age of participants was 35.1 (6.2) years at first brain MRI. The criteria for definite MS were based on the revised McDonald's criteria (2010). Six among 25 patients developed clinical symptom consistent with criteria for definite MS. The progression rate from RIS to definite MS was 1.5 (95% confidence interval (CI) 0.54, 3.17) per 100 person-months based on 480 person-months of follow-up. Multivariate analysis revealed that the presence of contrast-enhancing lesions on the initial MRI was marginally significantly associated with MS (hazard ratio 1.83, 95% CI 0.98, 3.45, p=0.060). This is the first estimate of progression rate from RIS to definite MS in Iran. The progression rates from RIS to definite MS in these participants are high and intensive follow-up and intervention strategies are recommended for these high risk individuals. A larger study is warranted to assess this risk in greater detail.