coma usually have big risks that comes with it. i dont think humans are capable hibernation like squirrels or some insects. the more extreme ones can go into cryptobiosis.

Coma has body functions still working, so blood pumping, ceels dying and regenerating, which means if you had cancer it would grow, if you had kidney failure, your blood cleanup would fail. Only thing AFAIK medically induced coma does is help with anything that the brain might be doing to itself like swelling or other complications.

Hibernation supposedly would slow down all metabolical functions, so less to no, blood flow and so on.