Moreover, after adjusting for the prespecified predictors and variables with p < 0.1 in the univariable analysis, including age, sex, hypertension, diabetes mellitus, previous ICH, ICH volume and time to CT, the presence of the APOE ε4 allele (OR 3.605, 95% CI 1.152–11.279, p = 0.028), but not that of the APOE ε2 allele (OR 0.320, 95% CI 0.070–1.463, p = 0.142), was associated with the island sign (Table 3). Here, APOE is linked to diabetes mellitus.