Social security expenditures will grow from 4% of gdp to 6% of gdp from 2000-2035. By 2035 Medicare will grow to 8% of GDP. So in a bit over a decade, one out of every six dollars produced in the economy will be going to take care of retired people.
All health care costs in the US are going up. The US government has to pay HMO corporation profits, Americans have to pay higher drug prices unlike other countries. The government can continue paying current Medicare rates, or it can hand more money to health companies if it wants to. As the government is still handing extra money to health companies apparently no one thinks it is a problem as of yet.