Cognitive dysfunction is common in pediatric-onset multiple sclerosis, but long-term data on cognitive maturation in these patients are sparse. We report the clinical features and cognitive trajectories in 4 pediatric-onset multiple sclerosis patients who were 10 years or younger at first attack and were followed between 1998 and 2010. Relapses in all 4 patients were frequent early in the disease and became infrequent or absent over time. Declines on neuropsychological testing were most pronounced on measures of processing speed, specifically visuomotor speed, and executive control requiring mental sequencing and set shifting, whereas global intellectual ability and phonemic fluency remained stable or improved over time. These case studies demonstrate a negative impact of multiple sclerosis on cognitive development in the long term and suggest that continued observation into adulthood is required to appreciate the vocational consequences of pediatric-onset multiple sclerosis.
Keywords: cognitive trajectories; longitudinal study; multiple sclerosis.