Patients with obesity not only have a higher risk of pediatric multiple sclerosis (MS), but they also do not respond as well to first-line medications.
Rising rates of overweight and obesity have been linked to greater prevalence of poor health outcomes. Among those weight-related health issues is a greater susceptibility to inflammatory and autoimmune diseases. However, there has been little research on the association between weight and risk of pediatric multiple sclerosis (MS).
A new study published in JAMA Neurology has found that patients with obesity not only have a higher risk of pediatric MS, but they also did not respond as well to first-line medications. The researchers analyzed 453 patients with pediatric MS using records at the Center for MS in Childhood and Adolescence in Göttingen, Germany. The patients all had body mass index (BMI) measurements taken within 6 months of their diagnosis and had MS onset before 18 years of age.
Among the patients with MS, 27.8% had a BMI greater than the 90th percentile, which would make them be considered overweight or obese. Of these patients, 13.0% were in the 90th to 97th percentile (overweight) and 14.8% had a BMI greater than the 97th percentile (obese). In both boys and girls, high BMI was associated with a significantly increased risk of pediatric MS.
In addition to the correlation between weight and MS risk, the researchers also found an association between BMI and outcomes. Prior to treatment, the relapse rate was similar between patients who were considered nonoverweight, overweight, and obese. However, patients who were obese had more relapses during first-line treatment with the disease-modifying therapies interferon b and glatiramer acetate. Patients whose BMI was greater than the 99.5th percentile (extremely obese) had the worst response to these therapies (annual relapse rate, 1.37; 95% CI, 1.0-1.9; P  <.001). The switch rate to a second-line treatment was approximately 50% higher, as well.
The researchers also assessed magnetic resonance imaging activity at diagnosis, the interval between first and second MS attacks, relapse pretreatment, and disability progression, and they found that there was no evidence that a high BMI was associated with a more active inflammatory process.
They did note that because the center where the patients were studied is a tertiary referral center, the patients included in the study might have had less benign disease. Also, the BMI measurements taken within the first 6 months of diagnosis might not have reflected predisease BMI.
“The findings do not indicate that obesity promotes greater disease activity, but pharmacokinetic factors are more likely associated with treatment response,” the authors concluded. “This suggestion may have relevant management implications given that a healthy weight may potentially optimize treatment outcomes and reduce disease-related burden and health care costs.”
Huppke B, Ellenberger D, Hummel H, et al. Association of obesity with multiple sclerosis risk and response to first-line disease modifying drugs in children [published online July 15, 2019]. JAMA Neurol. doi: 10.1001/jamaneurol.2019.1997.