"leading to death" isn't exact enough for "suicidal" I don't think; I think suicidal people are actively trying to die with their act.

But taking an overdose, for example, is not going to be seen as just self-harm since no one is going to know the person "didn't mean it" until they recover and is going to be an emergency situation to those around one.

Anything "messy" (loss of blood, for example) or medical (needing stitches or any worry about infection, etc.) is probably going to be seen in the same light if you're not "there"/are "out" when someone notices.

Mostly, if the people around you can't "deal" with you, they'll probably declare an "emergency" and that will determine how "serious" the situation is.

But harming yourself is harming yourself, whether you are a 3 pack a day smoker, or anorexic, or doing other forms of SI in any way/shape/form. None of them is "better" or "worse" than feeling like you should die.