Kaidence is a newly-introduced variation of musical, rhythmic Cadence. Kaidence entered the Top 1000 in 2013, the same year it was rumored to be the frontrunner for Kim and Kanye's daughter. (It was wrong, of course - Kim and Kanye named their daughter North.)
The trouble with the Kaidence spelling -- or should we say, one of the troubles -- is that it introduces pronunciation confusion. Does the first syllable rhyme with may or my? The advantage of Kaidence is that the short form can more plausibly be Kai, fresher than Kady or Kay.