What ailment is associated with the hardening of the arteries? I used to think it was code word for dementia.

Atherosclerosis. Hardening of the arteries, atherosclerosis, occurs when fat, cholesterol, and other substances build up in the bloodstream and causes arteries to narrow and harden. Over time, these plaques can block the arteries and cause symptoms and problems throughout the body, including a stroke. However depending on the extent and location, hardening of the arteries may or may not result in dementia.
Circulatory problems. In the brain can lead to dementia, but hardening of the arteries can occur in any part of the body.