Abstract
BACKGROUND: Hepatitis B infection and vaccination against it have been implicated in the potential triggering or flare of some autoimmune diseases, including rheumatoid arthritis (RA). However, the safety of hepatitis B vaccination in patients with pre-existing RA is not known. OBJECTIVES: To assess the safety and antibody response of immunisation with a recombinant DNA hepatitis B vaccine in patients with RA. PATIENTS AND METHODS: The study comprised 44 patients with RA, of whom 22 received three doses (the second and third dose being given after one and six months) of a recombinant DNA hepatitis B vaccine (study group) and 22 did not receive the vaccine (control group). Both groups had comparable proportions of women and similar mean age (51 years). Clinical assessment before and two and seven months after the first immunisation included evaluation of daytime pain with a 10 cm visual analogue scale, duration of morning stiffness, and number of tender and swollen joints. Erythrocyte sedimentation rate (ESR) and C reactive protein (CRP) were measured at each visit. Antibodies to hepatitis B surface antigen (HBsAg) were determined by a commercial enzyme linked immunosorbent assay (ELISA) test kit. RESULTS: Hepatitis B vaccination was not associated with an appreciable deterioration in any clinical or laboratory measure of disease. The measures of disease activity of the patients and controls during the study period did not differ significantly: p=0.76 for daytime pain, p=0.1 for morning stiffness, p=0.24 and p=0.3 for tender and swollen joints respectively, p=0.08 for CRP, and p=0.12 for ESR. Fifteen of the 22 patients responded to vaccination, with an antibody level against HBsAg of 10 IU/l after seven months. Lack of response was associated with older age and higher scores of daytime pain. CONCLUSIONS: Hepatitis B vaccination is safe in RA and produces antibodies in 68% of the patients.