In addition, data indicate that BMI is directly proportional to the risk for pediatric MS. Vigorous activity, however, is associated with decreased risk of pediatric MS, a decreased number of T2 lesions, and a decreased relapse rate, according to a Canadian study.
Role of Risk Genes and Genetic Ancestry in Pediatric MS
Genetics may play a key role in the development of early-onset pediatric MS. Researchers are analyzing data in the United States for people of multiple genetic ancestries. Of 110 nonhuman leukocyte antigen (HLA) risk variants for adult MS, 36 may increase the risk of pediatric MS, either at the level of single-nucleotide polymorphisms (SNPs) or as an aggregate genetic risk factor. The effect size of each SNP is greater in children than in adults; each SNP may increase the risk of MS by twofold or more.
Imaging Efforts
Imaging could improve understanding of pediatric MS. National and international efforts to standardize protocols for 3-T imaging, volumetric scans, and diffusion tensor imaging (DTI) are under way. DTI already has revealed abnormal fractional anisotropy in pediatric MS, and this abnormality is associated with cognitive difficulty. MRI and optical coherence tomography (OCT) help to distinguish between MS, neuromyelitis optica (NMO), and acute disseminated encephalomyelitis (ADEM).
OCT imaging in children indicates similar levels of neuronal and axonal injury as in adults, despite better visual recovery in children. In a study published in the Multiple Sclerosis Journal, boys with pediatric MS were found to have greater axonal loss than girls with pediatric MS.
Testing DMTs’ Efficacy
Several studies of DMTs in pediatric MS are under way. PARADIGMS is an ongoing, 24-month, double-blind, double-randomized trial investigating the effect of fingolimod on relapse rate in pediatric MS. The control group is receiving interferons, and 3% of patients to date are prepubertal. Enrollment remains open, and the investigators hope to recruit more prepubertal patients. Studies were also launched for the two other oral disease-modifying agents, teriflunomide and dimethyl fumarate.
Observational registries are studying the safety and clinical experience with disease modifying agents in children. Investigators recently published data for 100 children in an Italian registry of patients with MS treated with natalizumab. The treatment decreased relapse rate to 0.1. Approximately 28% of the population had no evidence of disease activity. The drug appeared to be well tolerated in children and to be efficacious.
—Erica Tricarico
Suggested Reading
Belman AL, Krupp LB, Olsen CS, et al. Characteristics of children and adolescents with multiple sclerosis. Pediatrics. 2016;138(1).