MMP9 and migraine disorder: It should be noted that the relationship between MMP-9 and BMI could be one of the molecular features to distinguish patients with migraine without aura from migraine with aura, and is maintained by the different correlation direction and the significant differences in the slopes of the regression curves (p = 0.0321), as well as by the high value of the correlation difference index (∆rS = 0.9430) (Figure 3).