Obesity and Disease Activity in Pediatric-Onset Multiple Sclerosis

OBJECTIVE: To determine whether body mass index (BMI) at diagnosis of pediatric-onset multiple sclerosis (MS) predicts disease activity, including annualized relapse rate (ARR) and new MRI lesions.BACKGROUND: Obesity in childhood and adolescence has been shown to be a risk factor for developing MS, particularly amongst females. It is not known whether obesity modifies disease course in established MS. Animal studies suggest an association between obesity and inflammation, with leptin promoting pro-inflammatory T cells and attenuating Treg responses.DESIGN/METHODS: This was a multi-center retrospective observational study, with preliminary analysis of 50 adults with pediatric-onset MS, 74[percnt] female, mean age 22.8+/-3.5 years, mean follow up 8+/-3.9 years. BMI at MS diagnosis was standardized for age and sex based on WHO data. We investigated the relationship between BMI and number of relapses using a quasi-Poisson model corrected for age, sex, and disease modifying therapy use, and an offset log of disease duration. In secondary analyses, the association between BMI and new T2 or T1 gadolinium-enhancing lesions annually was modelled using a repeated measures analysis.RESULTS: Mean BMI z-score adjusted for age and sex at MS diagnosis was 0.93, with 30[percnt] overweight and 22[percnt] obese. Mean ARR was 0.88+/-0.63 and median EDSS at last follow up was 1 (range 0-6.5). 77[percnt] developed new lesions on MRI brain at 1 year. The model constructed to predict number of relapses (p-value 0.18) and the model constructed to predict MRI lesions (p-value 0.78) did not have sufficient data to show evidence of a difference based on BMI at MS diagnosis.CONCLUSIONS: About half of participants were overweight or obese at diagnosis in this pediatric-onset MS cohort of 50, but no association was found between BMI at MS diagnosis and disease activity. Larger studies are needed to confirm this finding. Disclosure: Dr. Krysko has nothing to disclose. Dr. Yeh has nothing to disclose. Dr. Hanwell has nothing to disclose. Dr. Cohen has nothing to disclose. Dr. Rotstein has received personal compensation for activities with Sanofi-Aventis, Novartis, and EMD Serono.