Obesity associated with risk of pediatric MS

New research has linked obesity in adolescent girls with an increased risk of pediatric multiple sclerosis (MS) or clinically isolated syndrome (CIS), a precursor to MS. Weight did not appear to heighten risk among adolescent boys.

Researchers analyzed data for 75 children aged 2 to 18 years who were diagnosed with demyelinating diseases and 913,097 healthy controls from the Kaiser Permanente Southern California Pediatric Acquired Demyelinating Diseases Cohort from 2004 through 2010. Diagnosis of MS was based on 2 or more episodes of demyelination in the central nervous system. Body mass index before onset of symptoms was used to classify the children as normal weight, overweight, moderately obese, or extremely obese.

Nearly 51% of the children with MS or CIS were overweight or obese compared with 37% of controls. Findings showed that the girls who were extremely obese were nearly 4 times more likely to be diagnosed with MS or CIS and the girls who were moderately obese were almost twice as likely to be diagnosed compared with girls of normal weight. There was no association between obesity and MS or CIS for adolescent boys.

The researchers suggest that fluctuations in estrogen in obese, peripubescent girls combined with the low-level systemic inflammation associated with obesity may accelerate the onset of MS or CIS into adolescence from young adulthood, although they say it is unclear why obesity and hormones do not appear to affect adolescent boys in a similar way.

They caution that although MS is rare among children and does not warrant screening of all obese teenagers for the disease, the childhood obesity epidemic is likely to lead to increased morbidity from MS and CIS, especially among adolescent girls.