decrepitude vs impairment

decrepitude and impairment both are nouns.

Word	Noun	Adjective	Verb	Adverb
decrepitude	Yes	No	No	No
impairment	Yes	No	No	No

As nouns, impairment is a hypernym of decrepitude; that is, impairment is a word with a broader meaning than decrepitude:

Other hypernyms of decrepitude include deterioration.

decrepitude (noun)	impairment (noun)
a state of deterioration due to old age or long use	damage that results in a reduction of strength or quality
The quality or state of being wasted and weakened by or as if by the infirmities of old age.	the act of making something futile and useless (as by routine)
	the occurrence of a change for the worse
	the condition of being unable to perform as a consequence of physical or mental unfitness
	a symptom of reduced quality or strength