I am in Canada right now as an international student and I have a 7 year gap between now and my prior study period. So I don't think gap in years matter at all.
What CIC is quite concerned about is how your new program of study will fit into your present career and what you intend to do after you finish. Also, they will look into your funding. And of course your present ties to your home country.
If it is just years gap that you worry about, it's a non-issue.
Good luck.