In my opinion, the fact you got sober is a sign of strength, not weakness. You should be proud of yourself and present your story with confidence in an interview if you are asked about your medical leave. I would much rather accept someone into a residency program that has learned to manage a chronic disease than someone who has not faced a tough challenge. That's my 2 cents (but I would get some other opinions as I am not on an admissions board). You would get my vote though!
