SV2A and Alzheimer disease: To reveal the relationship between CSF SV2A and cognitive ability in the AD group, a correlation analysis was also performed between CSF SV2A and cognitive scores, which showed a significant positive correlation between CSF SV2A levels and MMSE (r = 0.3928, p = 0.0002) and MOCA (r = 0.3905, p = 0.0002) (Fig. 2b-c).