Although significant differences were found between the groups for age [F(1,183) = 7.01; p = 0.008], we did not find significant differences in age among the three different COMT genotypes for fibromyalgia patients [F(2,105) = 0.254, p = 0.776] or for the HC group [F(2,74) = 1.982, p = 0.158]. Here, COMT is linked to fibromyalgia.