Medicare and Medicaid remain the nation’s largest fiscal challenge. If we needed any reminder of that the nonpartisan Congressional Budget Office has weighed in with long-term estimates of the unfounded liabilities of these programs. CBO estimates under reasonable assumptions that these programs will grow from the current 4% of GDP to 19% of GDP by the year 2082. This, along with maintaining existing Social Security benefits and financing will cause the size of the Federal government to double.
http://cbo.gov/ftpdocs/88xx/doc8877/12-13-LTBO.pdf