Speaking to Ian Branning for Real Radio Yorkshire, McFadden suggested that Horan would follow in his footsteps and leave his bandmates to go solo.
Of what boyband members might quit their current acts, McFadden said: "I reckon from One Direction, probably Niall.
"He comes across as the guy who'll probably follow in my steps and Robbie [Williams]'s steps and be the first to leave.
"All the ones that leave first always have that same kind of twinkle in their eye; they're a bit bold, a bit naughty!"
He continued: "I reckon Niall's the naughty one. Maybe because he's Irish I suppose and the rest of the boys are from England, but he does remind me of the boys from Westlife quite a bit.
"I don't know what it is, maybe it's his accent. He has a twinkle in his eye though and I've seen that twinkle before in the mirror! He's gonna cause trouble."
After suggesting that Harry Styles is "too chilled" to quit the boyband, McFadden added: "[Niall will say,] 'I'm out of here'.
"He'll be full of whiskey and Guinness and he'll do something. Just have that feeling, just a gut feeling."
McFadden quit Westlife in 2004 and releases his fourth solo album The Irish Connection via BMF Records/EMI on March 4.
Earlier this month a One Direction spokesman denied rumours that Zayn Malik would be quitting the band because he had become disillusioned with fame.
Hear Ian Brannan's full interview with Brian McFadden on Friday afternoon (February 15) from 4pm on 106-108 FM Real Radio Yorkshire and online at Real Radio Yorkshire.
One Direction perform at Madison Square Garden - photo gallery: