Fig. 3

The sex-stratified relationship between plasma testosterone levels and CSF p-Tau levels overall (a, b) and by APOE4 status (c, d). Using multivariable linear regression, we found negative associations between testosterone and p-Tau levels in both women and men. Although the testosterone X APOE4 status interactions were not significant in either sex, the significant testosterone X APOE4 interaction in the overall sample appeared to be driven by women. When analyses were stratified by sex, we found that the testosterone X APOE4 status interaction on p-Tau levels was driven by women. CSF cerebrospinal fluid, p-Tau phosphorylated Tau, APOE4 apolipoprotein E ε4 allele. Analyses adjusted for age, education, BMI, and self-reported history of cardiovascular events