APOE and dementia: Participants with persistent SCC had twofold increased odds of developing all-cause dementia over the 17-year follow-up (OR 2.15; 95%CI 1.52–3.06; p-value < 0.0001), but if participants with persistent SCC were also APOE ε4 carriers (APOE ε4 +), the odds increased to 5.35 (95%CI 3.25–8.81, p-value < 0.0001; Table 2).