In the subgroup with DFNB1-related deafness and CI activation after1 year, hereafter referred to as older, no correlation between MMP-9_0 and LEAQ_0was found, a positive correlation between BDNF_0 and LEAQ_0 score (p = 0.03,Rho = 0.4) and a negative correlation between pro-BDNF_0/BDNF_0 ratio and LEAQ_0score (p = 0.01, Rho = –0.5) were found.Testing between MMP-9_0, BDNF_0, and pro-BDNF_0/BDNF_0 ratio with LEAQ_8 did notshow any correlation. This evidence concerns the gene MMP9 and deafness.