"I don't give a fig" degrees of comparison

It's absolutely OK to say something like
"My liver pain bothers me more than my nose bleeding"

right?
But what about the opposite attitude. If I don't really care about something, can I compare it with not taking care about something else, for example:
"I don't give a fig about my HIV even more than about my caries"?
Is it correct from the language usage point of view? or "I don't give a fig" has the constant value which is not comparable?