Silver Book Fact
The prevalence of silent cerebral infarction in those ages 55-64 is about 11%. Prevalence increases to 22% for those 65-69, 28% for those 70-74, 32% for those 75-79, 40% for those 80-85, and 43% for those above age 85.
Rosamond W, Flegal K, Furie K, Go A, et al. Heart Disease and Stroke Statistics- 2008 Update. Circulation. 2008; 117. http://circ.ahajournals.org/cgi/content/short/117/4/e25