comparing anti-hepatitis b antibody level in iranian obese or overweight with non-obese cases

background: there is a controversy about the relation between anti-hepatitis b (anti-hbs) antibody level and obesity. we designed this study to compare the vaccine efficacy in obese/overweight and non-obese cases. methods: in this cross-sectional study, 242 obese/overweight and 85 non-obese individuals were participated. cases were selected from a referral clinic for obesity and a referral hepatology clinic, both in tehran, iran. results: obese cases had lower percentage of liver diseases (66.9% vs. 100%, p<0.001) but higher hepatitis b vaccination history (74.9% vs. 51.2%, p<0.001). median±inter-quartile range of anti-hbs titer in obese cases was significantly lower than controls (48.5±194.5 vs. 100±557.6, p=0.012). conclusion: the level of anti-hbs surface antigen antibody’s titer in obese cases without liver disease is lower than control group. therefore, a suitable strategy is needed to overcome this problem, which can be the use of longer needles for vaccination.