It's mad to be found in the thick of things (6)
I believe the answer is:
amidst
'in the thick of things' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.
'it's mad to be' is the wordplay.
'to be' indicates anagramming the letters.
'its'+'mad'='itsmad'
'itsmad' is an anagram of 'AMIDST'.
'found' is the link.
Can you help me to learn more?
(Other definitions for amidst that I've seen before include "In the thick of" , "contained" , "In the middle of the morning I would have a piece of crust" , "Surrounded by" , "In the centre of" .)