Gets old leaders to acknowledge ghastly economic situation (4)
I believe the answer is:
ages
'gets old' is the definition.
('age' can be a synonym of 'get old')
'leaders to acknowledge ghastly economic situation' is the wordplay.
'leaders to' indicates taking the first letters (I've seen 'leader to' mean this (the letter which leads the word)).
The initial letters of 'acknowledge ghastly economic situation' is 'AGES'.
(Other definitions for ages that I've seen before include "A long time (colloq.)" , "Yonks" , "Historic periods or prolonged time" , "Sage (anag)" , "Long periods" .)