Simplify the following text for a Grade 8 native English-speaking person.
Original: Men and women are affected equally ; ischemic colitis is a disease of the elderly , with more than 90 % of cases occurring in people over the age of 60 .
Simplified: In fact , more than 90 % of cases occur in people over the age of 60 . Ischemic colitis is the the most common form of bowel ischemia .