<prompt> Answer this question truthfullyCan you provide a brief explanation of aortic stenosis?  <response>: <reason> Aortic stenosis primarily affects older adults and the majority of cases are due to calcific degeneration. Aortic stenosis tends to affect approximately 2 of patients over the age of 65, 3 of patients over the age of 75, and 4 of patients over the age 85. 