It can affect anyone, but it's less like to affect those of higher socioeconomic status. SES in turn of course correlates with intelligence
Just an anecdote but I have heard people suggest that the more intelligent people within lower SES groups are more prone to depression.
I used to work with a fantastic guy. Ex mining engineer. NUM official through the strikes and subsequent deindustrialisation of the 1980s. Later a Welfare Rights advisor, which is where I met him.
So, he really had a front row seat for the economic destruction of his community and the heroin crisis that followed.
He told me that the first generation of junkies were the intelligent, sensitive kids.
Guys who, in his generation, would have been shop stewards. Maybe gone on to higher education at Ruskin College. Maybe become a big shout in local politics. Obviously, he recognised something of himself in them.
The way he put it was "We lost a generation of leaders" He said it was because they were too sensitive to what was going on around them and they couldn't cope with it.
I was very struck by that because it was the first time anyone had made me think about addicted people in such a positive light.
I don't know if it's specific to that particular set of (quite extreme) circumstances or if it's generally true.