APOE and dementia: APOE ɛ4 carriership only predicted dementia in the low‐risk tertile of the AD‐PRSs (39‐SNPs AD‐PRS: HR 1.72; 95% CI 1.01–2.92, P = .05, 1e–5 AD‐PRS: HR 3.66; 95% CI 1.99–6.73, P = 3 × 10–5; Table 3).