Table 2.

Associations between APOE e4 presence and brain MRI variables (uncorrected for type-1 error)

	Partially adjusted				Fully adjusted
	b	Lower 95% CI	Upper 95% CI	p	b	Lower 95% CI	Upper 95% CI	p
Association with APOE e4 presence
gFA	−0.034	−0.092	0.024	0.255	−0.034	−0.092	0.025	0.259
gMD	0.027	−0.030	0.085	0.352	0.026	−0.031	0.084	0.369
Left hippocampus	−0.005	−0.058	0.049	0.861	−0.003	−0.057	0.051	0.911
Right hippocampus	−0.005	−0.058	0.048	0.858	0.002	−0.052	0.055	0.954
Total GM (normalised)	0.012	−0.031	0.055	0.585	0.010	−0.033	0.053	0.645
Total WM (normalised)	0.029	−0.025	0.082	0.294	0.019	−0.035	0.072	0.496
Total WM hyperintensities	0.093	0.041	0.145	4 × 10−4	0.088	0.036	0.139	0.001
APOE e4*age interaction
gFA	<0.001	−0.008	0.008	0.985	<0.001	−0.008	0.009	0.924
gMD	0.002	−0.006	0.010	0.661	0.001	−0.007	0.009	0.768
Left hippocampus	−0.004	−0.012	0.003	0.252	−0.004	−0.012	0.004	0.291
Right hippocampus	−0.004	−0.012	0.004	0.308	−0.004	−0.011	0.004	0.342
Total GM (normalised)	0.001	−0.005	0.007	0.842	0.001	−0.005	0.007	0.638
Total WM (normalised)	−0.004	−0.011	0.004	0.340	−0.004	−0.012	0.003	0.258
Total WM hyperintensities	−0.001	−0.008	0.006	0.816	−0.002	−0.009	0.005	0.614

Partially adjusted: APOE e4 presence vs. absence plus 8 genetic principal components, assessment centre, genetic array, age in years and sex. Bold typeface denotes p < 0.05. Fully adjusted: (also) Townsend deprivation scores, self-reported diagnosed diabetes; hypertension; coronary heart disease, ever vs. never smoking.

GM grey matter; WM white matter; FA fractional anisotropy; MD mean diffusivity; b standardised beta; CI confidence interval; APOE apolipoprotein e; MRI magnetic resonance imaging