He was the youngest winner, at 24, of the Perrier Award for comedy, and his 1990 show at the Edinburgh Festival fringe was influential in the development of stand-up from an extended list of pre-prepared jokes to a narrative performance.
London-born but very much Irish, Hughes was perhaps best known as a panellist on the BBC’s Never Mind The Buzzcocks, and for writing and starring in his own sitcom, Sean’s Show in the early 1990s.
In it he broke the fourth wall and addressed the audience directly, a device that had been used in the 1950s by George Burns and in the 1980s by Garry Shandling. But Hughes made it his own, with a distinctly surreal take on his surroundings.
He had written in recent years of his long battle with alcohol.
He had once stopped for a while because he was “drinking too much”, he said in the Irish Times, only to take it up again.
He wrote: “The other night, pretty drunk at the end of the evening, my friend asked if I wanted to go for a ‘proper’ drink.
“Thank God those days are over for me now. I quit drinking totally for a couple of years because I was having too many ‘proper’ drinks. I knew I was drinking too much when I had to be put out at a party.
“I don’t mean I was asked to leave. My jacket was on fire.”
He continued: “When I started drinking again, I thought my friends would be concerned, but they welcomed my return with a ‘great to have you back’ attitude.
“Apparently I’m tedious when sober. People were uncomfortable when I wasn’t drinking. It made them question their own habits.”
In another piece in the newspaper from the same year, Hughes said he had pushed his body “to extreme hedonistic limits”.
Hughes’ later career included appearances on Coronation Street and The Last Detective. He returned to Edinburgh in 2007 after a seven-year break, with a show called The Right Side Of Wrong.
He was also a writer and had completed two collections of prose and poetry, including Sean’s Book. He wrote the best-selling novels The Detainees and It’s What He Would Have Wanted.
Hughes is survived by his two brothers, Alan and Martin.