Similarly to what was observed for serum levels of gp130/sIL-6Rb, important results were obtained analyzing the values of sTNF-R1 and sTNF-R2 versus disease duration: in particular a positive strong correlation was found between sTNF-R1 circulating levels and disease duration in MO-BD subgroup, thus suggesting as previously reported that BD appears to have a less aggressive clinical course over time related to disease duration (60). This evidence concerns the gene IL6ST and Behcet disease.