I've heard that 20% of people account for 80% of health care costs.
I'd like current information about this.
What percentage of people spend the majority of health care costs?  
For the small percentage of people who spend the majority of health
care costs, what is the breakdown of those costs?
What are the demographic and disease characteristics of the people who
spend the majority of health care costs.

Partial Answer for you.  Health care costs are exponentially related
to age.  For example: To live an average lifespan of 55 years old-
individuals would spend about $10,000 on health care for their entire
life.  65 years old- $100,000.  75 years old- $1,000,000.  85 years
old- $10,000,000.

Earth shattering news: it costs more to live longer.