Troubled by the worst conclusion that followed (6)
I believe the answer is:
tailed
'that followed' is the definition.
(I've seen this before)
'troubled by the' is the wordplay.
'troubled' becomes 'ailed' ('ail' can be a synonym of 'trouble').
'by' means one lot of letters go next to another.
'the' becomes 't' (the is pronounced as a 't' sound in some dialects).
'ailed' after 't' is 'TAILED'.
'worst conclusion' acts as a link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for tailed that I've seen before include "Dogged" , "Followed like rear appendage" , "Followed, tracked" , "as a dog at the end" , "Followed by private detective, having rear appendage" .)