APOE and dementia: We subsequently tested for interaction between SBP and APOE ɛ4 in multivariable analyses, and found association with increased risk of recurrent ICH, small vessel ischaemic stroke, incident dementia and incident gait impairment (Supplementary Table 6, interaction P < 0.05 for ICH recurrence, small vessel ischaemic stroke, dementia and gait impairment).