OCD is a mental disability so it affects the brain.
Sometimes depression can be a part of it, I have borderline OCD. Usually axiety is the number one cause of OCD.
Quite significantly as that body part is no longer there.
Every part of the body is vulnerable
Eye
Lung
eyes
the head
Tongue
Bones
the left side of your head
Depressants slow (or depress) the functioning of the entire body.
It affects the kidney.