APOE and Cognitive impairment: We did find evidence for sex differences across associations with both Lifetime incarceration (IRR = 0.76, 95% CI = [0.59, 0.97], P = 0.025) and possessing a single APOE-ε4 allele (IRR = 0.84, 95% CI = [0.72, 0.98], P = 0.024), suggesting that males who were previously incarcerated or had a single APOE-ε4 allele experienced a lower risk level for cognitive impairment relative to females with the same status/background (Models 3.3–4).