substance abuser vs worker

substance abuser and worker both are nouns.

Word	Noun	Adjective	Verb	Adverb
substance abuser	Yes	No	No	No
worker	Yes	No	No	No

As nouns, worker is a hypernym of substance abuser; that is, worker is a word with a broader meaning than substance abuser:

Other hypernyms of substance abuser include actor, doer.

substance abuser (noun)	worker (noun)
a person who takes drugs	sterile member of a colony of social insects that forages for food and cares for the larvae
	a person who works at a specific occupation
	a member of the working class (not necessarily employed)
	a person who acts and gets things done