The presence of a NOTCH3 variant was associated with at least 2-fold higher odds of any stroke (odds ratio [OR], 2.16; 95% CI, 1.67-2.74; P = 3.2 × 10−8), ischemic stroke (OR, 2.65; 95% CI, 1.96-3.50, P = 5.9 × 10−9), and intracerebral hemorrhage (OR, 2.42; 95% CI, 1.23-4.22; P = .01). Here, NOTCH3 is linked to ischemic stroke.