Pediatric Multiple Sclerosis in Rio de Janeiro: Secondary Progression and Disability.

BACKGROUND: The onset of multiple sclerosis (MS) in 2% to 10% of cases occurs prior to 18 years of age. Early age onset appears to affect some aspects of multiple sclerosis. The objective of our study was to evaluate the prevalence, the clinical and demographic characteristics, and the disease progression in a sample of pediatric multiple sclerosis patients from a mixed population. METHODS: In a cross-sectional design, the prevalence, demographic characteristics, and initial clinical forms were compared between 75 cases of pediatric multiple sclerosis (PMS) and 689 adults with MS. Sixty-five PMS patients with complete data and 260 randomly selected adults with relapsing-remitting multiple sclerosis were compared. A Kaplan-Meier analysis was conducted to compare the age at and time to Expanded Disability Status Scale (EDSS) 3, EDSS 6, and secondary progressive multiple sclerosis (SPMS). RESULTS: A total of 9.8% of all MS cases with available data were PMS. All cases of PMS consisted of relapsing-remitting multiple sclerosis. Brazilians of African descent comprised 34.6% of the sample, and the female-to-male ratio was 2.4:1. At the first attack, motor alterations were more common. Benign forms were more common in PMS (84.6% versus 62.2%). Fewer PMS patients reached EDSS 6 (11.6% versus 25.4%) (P = 0.0017) and SPMS (11.1% versus 28.1%) (P = 0.005). PMS patients took longer to reach EDSS 3 (P = 0.017), EDSS 6 (P = 0.001), and SPMS (P < 0.001); however, they reached EDSS 3 earlier (P < 0.001). CONCLUSIONS: In this mixed cohort, the prevalence of PMS was similar to that reported in other studies, and the pediatric patients had a more benign course than adults with MS.

African ancestry is a predictor factor to secondary progression in clinical course of multiple sclerosis.

Background. Studies on the clinical course of multiple sclerosis have indicated that certain initial clinical factors are predictive of disease progression. Regions with a low prevalence for disease, which have environmental and genetic factors that differ from areas of high prevalence, lack studies on the progressive course and disabling characteristics of the disease. Objective. To analyse the long-term evolution to the progressive phase of the relapsing-remitting multiple sclerosis and its prognosis factors in mixed population. Methods. We performed a survival study and logistic regression to examine the influence of demographic and initial clinical factors on disease progression. Among 553 relapsing-remitting patients assisted at a Brazilian reference centre for multiple sclerosis, we reviewed the medical records of 150 patients who had a disease for ten or more years. Results. African ancestry was a factor that conferred more risk for secondary progression followed by age at the onset of the disease and the number of relapses in the year after diagnosis. A greater understanding of the influence of ancestry on prognosis serves to stimulate genetics and pharmacogenomics research and may clarify the poorly understood neurodegenerative progression of MS.

Differences in the progression of primary progressive multiple sclerosis in Brazilians of African descent versus white Brazilian patients.

Recent studies have suggested faster clinical progression and greater disability in multiple sclerosis patients of African descent. This study analysed the effect of ethnicity on progression and disability. Sixty-five patients with primary progressive multiple sclerosis were selected and classified as being of African descent or white. Time from onset of the disease until reaching Expanded Disability Status Scale grades 3, 6, and 8 was assessed, as well as irreversible disability (Expanded Disability Status Scale grade maintained for >or=6 months). In the African descent group, the median time to reach Expanded Disability Status Scale 3 was 1 year shorter (1 year vs 2 years, p= 0.02), and to reach Expanded Disability Status Scale 6 was 2 years shorter (3 years vs 5 years, p= 0.01) than in the group of white patients. According to the Kaplan-Meier survival curves, patients of African descent reached every disability stage faster than white patients (p= 0.03, p = 0.04, and p = 0.03, respectively, for Expanded Disability Status Scale grades 3, 6, and 8). As in United States and European patients of African descent, the more severe and faster progression of multiple sclerosis seen in Brazilian primary progressive multiple sclerosis patients of African descent suggests a possibly greater effect of ethnicity rather than environment on the progression of multiple sclerosis.

The reliability of specific primary progressive MS criteria in an ethnically diverse population.

UNLABELLED: Three different diagnostic criteria for primary progressive MS were recently proposed for Caucasian population of Western European region. OBJECTIVE: The objective of the study was to apply these criteria to a series of Brazilian patients with high ethnic diversity background to evaluate reproducibility and reliability. METHODS: 52 patients classified as form of the disease that is progressive from onset and followed between 2000 and 2006 were included. Thompson, McDonald and Polman criteria were applied based in clinical date and complementary exams. RESULTS: 72% fulfilled all three criteria with moderate agreement (p<0.001). Ten patients fulfilled at least one criterion and four failed to fulfill any of the three criteria. Strong agreement was found between Thompson and McDonald criteria (p<0.001), agreement was moderate between Thompson and Polman criteria (p<0.001) and weak agreement occurred between McDonald and Polman criteria (p=0.042). CONCLUSION: The main difference between these criteria is the change in the role of CSF, previously a prerequisite for diagnosis. Rigid diagnostic criteria as Thompson have higher specificity, should be used in clinical research protocols, while more flexible criteria as Polman facilitate the diagnosis of PPMS in neurological practice, particularly in initial stages of the disease, because of their potentially higher sensitivity.