Oh, why health costs increase? The basic reason why health costs increased is that health care is a good thing! Because today there is a lot more you can do! Consider all these expenses that are diagnostic. Cat scans, X-rays, MRIs and now the proton-powered whatever-it-is. Something that is the size of a football field, cost $50 million, and has all sorts of diagnostic powers. A lot of these technologies clearly reveal things that would not be revealed otherwise. There's no question about it. Diagnostics have improved. Technology has improved. You know, sending things through your blood stream to help in operations, instead of cutting you open. It's incredible. But these things are costly. But for older people longevity is increasing by a month each year. Now, whether that creates other problems with retirement and social security is another question. But, nevertheless, preserving life is a good thing.
Arrow also argues that the erosion of "professional standards" has been a driving force in the rapid inflation of health care costs. I have not seen any evidence of this other than the observational fact that different states have different standards, and different states have different per capita health care costs. But the one does not necessarily point to the other. Do readers know of any rigorous treatments of the question?