KLK6 and Alzheimer disease: BDNF (hazard ratio (HR) = 0.84, p = 2.47×10−2), KLK6 (HR = 0.45, p = 2.47×10−2), NPTXR (HR = 0.44, p = 2.47×10−2), TAFA5 (HR = 0.68, p = 2.92×10−2), and FLT1 (HR = 0.57, p = 3.07×10−2, Fig. 5A–B, Supplementary Table 11) exhibited significant protective associations, indicating their potential roles in reducing the risk of developing symptomatic AD when accumulated.