https://www.statnews.com/2020/03/03/who-is-getting-sick-and-how-sick-a-breakdown-of-coronavirus-risk-by-demographic-factors/ I'm trying to find the exact article, this isn't it, but there have been studies of co-morbidity with other conditions. (50% of men in China still smoke) and chronic respiratory issues add an additional 6%-7% chance of needing intensive care or dying.