3 ms·I'd say the most common pre-existing condition is being a heavy (ex-)smoker.by waps 13y agoI'd say the most common pre-existing condition is being a heavy (ex-)smoker.smsm42 13y agoBeing a smoker is not a disease, AFAIK. But again, HIPAA Title I as far as I know provides for uninterrupted coverage regardless of health conditions, doesn't it?waps 13y agoThat's probably why they call it a "pre-existing condition", not a disease.