Research study shows that people who were previously uninsured, have higher Medicare expenses. Study of 4,567 adults who didn’t have insurance prior to enrolling in Medicare. Once acquiring coverage, those with diabetes, heart disease or joint replacements had 21% higher medical expenditures through Medicare, than those who were previously insured. Article by McWilliams, Meara et al. Pubmed abstract in December 2009 Annals of Internal Medicine.