The S100B levels were significantly lower in the MDD group than in the HC group (H = 18.93, p = 0.021, η2 = 0.047), and the difference between genders was also significant, with significantly higher S100B levels in males than in females with MDD (H = 10.06, p < 0.001, η2 = 0.025) (Table 2). Here, S100B is linked to major depressive disorder.