Hepatitis B vaccination and the risk of childhood-onset multiple sclerosis.

OBJECTIVE To investigate whether vaccination against hepatitis B (HB) increases the risk of incident multiple sclerosis (MS) in childhood in the short and long terms. DESIGN Case-control study. SETTING Population-based study conducted in France from January 1, 1994, to December 31, 2003. PARTICIPANTS The case patients had incident MS with onset before age 16 years. Each case was individually matched for age, sex, and geographic location (current place of residence) to 12 control participants randomly selected from the general population of France. EXPOSURE Hepatitis B vaccine. MAIN OUTCOME MEASURE The risk of MS associated with HB vaccine exposure. RESULTS One hundred forty-three case patients with MS were matched to 1122 control participants. The rate of HB vaccination in the 3 years before the index date was approximately 32% for both cases and controls. Vaccination against HB within the 3-year study period was not associated with an increased rate of a first episode of MS (adjusted odds ratio, 1.03; 95% confidence interval, 0.62-1.69). The rate was also not increased for HB vaccination within 6 months of the index date or at any time since birth or as a function of the number of injections or the brand of HB vaccine. CONCLUSION Vaccination against HB does not seem to increase the risk of a first episode of MS in childhood.