The mean (SD) age at symptom onset for the 10 NOTCH3 mutation carriers was 80.5 (6.7) years, which was similar to that for the entire sample of ADSP EA cases (80.9 [9.1] years) and greater than age at onset of cognitive impairment among individuals with CADASIL (usually <50 years). Here, NOTCH3 is linked to Cognitive impairment.