Table 2.

Risk of late-life dementia with plasma Aβ levels 15 years prior to dementia diagnosis: HAAS Aβ sub-study

	β Amyloid quartiles (from low to high)				β Amyloid
Dementia sub-type	Q1 (n=166)	Q2 (n=167)	Q3 (n=167)	Q4 (n=167)	Per -1 S.D.
Aβ1-40
All AD	4.3 (1.9–9.8)*	3.0 (1.3–7.1)	1.8 (0.8–4.2)	1 (ref)†	2.1 (1.4–3.1)
Pure AD	4.0 (1.5–10.7)	2.8 (1.0–7.6)	1.1 (0.4–3.5)	1 (ref)†	2.1 (1.3–3.5)
Vascular dementia	1.5 (0.4–5.2)	1.1 (0.3–3.4)	1.2 (0.4–3.4)	1 (ref)	1.0 (0.6–1.8)
Aβ1-42
All AD	3.1 (1.2–8.0)	3.5 (1.4–8.7)	2.5 (1.0–6.3)	1 (ref)†	1.6 (1.1–2.3)
Pure AD	4.3 (1.2–15.9)	4.3 (1.2–15.3)	3.5 (1.0–12.6)	1 (ref)†	1.7 (1.1–2.6)
Vascular dementia	0.8 (0.2–2.9)	1.4 (0.5–4.3)	1.2 (0.4–3.6)	1 (ref)	0.9 (0.6–1.4)
Aβ1-40/Aβ1-42 ratio
All AD	0.5 (0.2–1.2)	0.7 (0.3–1.6)	1.0 (0.5–2.1)	1 (ref)	0.8 (0.6–1.0)
Pure AD	0.5 (0.2–1.4)	0.6 (0.2–1.6)	0.9 (0.4–2.1)	1 (ref)	0.7 (0.6–1.0)
Vascular dementia	1.2 (0.4–3.7)	1.1 (0.3–3.6)	1.4 (0.4–5.1)	1 (ref)	1.1 (0.7–1.7)

^*Hazard ratio (95% CI) adjusted for apolipoprotein E genotype, education and time from blood draw to censoring event;

^†p_{linear trend} < 0.05