Association of APOE genotype with CT markers of cerebral amyloid angiopathy in spontaneous intracerebral haemorrhage.

Background and objective: We investigated the association of APOE alleles with CT-based cerebral amyloid angiopathy (CAA) markers including subarachnoid extension (SAE) and finger-like projection (FLP).

Methods: We included patients with acute primary supratentorial intracerebral haemorrhage (ICH) from a multicentre cohort in China. First, the association of APOE with ICH location (lobar vs non-lobar) was evaluated. Next, the relationships of APOE with SAE, FLP, and the coexistence of the two (SAE+FLP) were evaluated.

Results: 533 patients with supratentorial ICH were enrolled. Among them were 138 patients with lobar ICH and 395 with non-lobar ICH. Compared with the non-lobar group, APOE ε4 (OR 1.894, 95% CI 1.138 to 3.154, p=0.014) and ε2/ε4 (OR 6.098, 95% CI 1.414 to 26.293, p=0.015) were associated with lobar ICH. With regard to CAA markers, APOE ε2 was associated with SAE (OR 2.109, 95% CI 1.167 to 3.810, p=0.013), ε4 was associated with FLP and SAE+FLP (OR 3.026, 95% CI 1.353 to 6.767, p=0.007; OR 3.514, 95% CI 1.485 to 8.316, p=0.004, respectively) and ε2/ε4 was associated with all three factors (SAH: OR 7.599, 95% CI 1.764 to 32.734, p=0.006; FLP: OR 20.333, 95% CI 3.278 to 126.137, p=0.001; SAE+FLP: OR 30.568, 95% CI 4.460 to 209.503, p<0.001) after adjusting for age, and remained significant after adjusting for age and ICH volume.

Conclusion: In patients with spontaneous supratentorial ICH, APOE ε2 and ε4 alleles were associated with SAE and FLP, respectively, suggesting APOE allele-specific effects on CT markers of CAA and their potential mechanisms.