Conversion of clinically isolated syndrome to multiple sclerosis: a prospective multi-center study in Eastern India

Abstract

Background In White populations more than 60% of clinically isolated syndrome (CIS) convert to multiple sclerosis (MS) on a long-term follow-up; several predictors for conversion have been identified. Objective This study aimed to determine the conversion rate and the predictors of conversion from CIS to MS (McDonald 2010) among Indians. The other objective was to evaluate the diagnostic accuracy of the new McDonald 2017 criteria in prediction of a second clinical attack. Methods Clinical and demographic data of CIS cohorts were collected. Baseline investigations included cerebrospinal magnetic resonance imaging (MRI) with contrast and cerebrospinal fluid (CSF) testing for oligoclonal band (OCB). Follow-up clinical and MRI examinations were performed annually for at least 24 months. Results Of the 82 subjects (age range 15–58 years), 36 (43.9%) converted to MS; 31/82 (37.8%) converted in 24 months. The predictors for conversion were earlier age of onset, CSF-OCB, cerebral MRI T2 lesion count, and periventricular and juxtacortical location of lesions. Twenty-two (26.83%) CIS fulfilled the McDonald MS 2017 criteria at baseline. Conclusion In this first prospective study of CIS in India, the risk factors for conversion are similar but the conversion rate to MS is lower than that in the western nations.

Ankstyvos išsėtinės sklerozės klinikiniai požymiai

“…That said, the 35.5% rate of con ver sion to MS found in our study could have increased if the study had as sessed a lon ger fol low-up pe riod. There is con flict ing ev i dence in the lit er a ture whether sociodemographic fac tors af fect con ver sion to MS. Accord ing to some stud ies, an early dis ease on set is re lated to a higher risk of de vel op ing MS [8,[11][12][13]. How ever, there is ev i dence that age does not af fect con ver sion to MS [7].…”

“…Ac cord ing to our re sults, 35.5% of pa tients con verted to MS, and di min ished sense of vi bra tion and proprioception was sta tis ti cally more likely to oc cur in the MS group. However, dif fer ent con ver sion rates have been shown worldwide: in Brazil it was found that 87.3% of clin i cally iso lated syn drome (CIS) pa tients con verted to MS dur ing 5-year follow-up pe riod [7], 43.9% con verted in an In dian study [8], and 85.4% in Tur key [9], re spec tively. How ever, ac cord ing to the study by Liao et al, only 11% of pa tients with acute dis sem i nated encephalomyelitis (ADEM) con vert to MS dur ing lon ger fol low-up pe ri ods [10].…”

Epidemiology and clinical features of demyelinating disorders in India

“…The latter were often referred to as optico spinal/Asian form of MS. 14,15 In hindsight, these were more likely to have been NMOSD as currently defined. Table 1 summarizes the studies [16][17][18][19][20][21][22][23][24][25][26][27][28] done since 1999 that describes clinical and demographic features of MS in India. The earlier studies published between 1999 and 2005 used Poser's criteria 29 for diagnosis, but the majority of studies employed Mc Donald 2010 30 or 2017 31 criteria.…”

Predictors of progression from a first demyelinating event to clinically definite multiple sclerosis

“…Many previous studies have examined a typically narrow set of predictors of progression from a first demyelinating event to clinically definite multiple sclerosis in a wide range of populations (recent examples include other studies 6–11 ). Such studies have highlighted that older age at first demyelinating event, optic neuritis, isolated sensory symptoms, any exposure to a disease-modifying drug, and normal MRI impart a more favourable prognosis.…”

“…Alternatively, first symptom location in the brainstem or the supratentorial region (compared to the optic pathways), 12 having at least one gadolinium-enhancing MRI lesion, and three or more periventricular lesions were factors associated with worse prognosis. 6 , 9 , 12 , 13 …”