New York City, August 12, 2003—Gaining access to Medicare coverage substantially improved uninsured older adults' use of clinical preventive measures such as cholesterol testing, mammography, and prostate exams, compared with a similar group of insured adults, according to a new study in the August 13 issue of the Journal of the American Medical Association (JAMA). "Many older uninsured Americans have great difficulty finding affordable health insurance coverage, or even any coverage at all," said Karen Davis, president of The Commonwealth Fund, which supported the study. "An early Medicare buy-in option for these adults would ensure greater access to potentially life-saving preventive tests, which makes sense both medically and economically." Prior to Medicare eligibility, only 41 percent of uninsured adults examined in the study received cholesterol testing, compared with 76 percent of insured adults—a difference of 35 percentage points—according to the article, "Impact of Medicare Coverage on Basic Clinical Services for Previously Uninsured Adults," by J. Michael McWilliams, M.D., Alan M. Zaslavsky, Ph.D., Ellen Meara, Ph.D., and John Ayanian, M.D., of Brigham and Women's Hospital and Harvard Medical School in Boston. Meanwhile, 46 percent of uninsured adults received mammograms, versus 76 percent of insured adults (a 30 percentage point difference). For prostate cancer screening, the disparity was even greater: 29 percent of the uninsured were given this test, compared with 74 percent of the insured (a 45 percentage point difference). Once uninsured adults became eligible for Medicare coverage, the differences in preventive testing rates between the two groups were dramatically reduced. Differences in cholesterol testing rates between previously uninsured and insured patients fell from 35 percentage points before Medicare eligibility to 18 percentage points after Medicare eligibility; differences in mammography testing rates dropped from 30 percentage points to 15 percentage points; and differences in prostate cancer screening rates fell from 45 percentage points to 20 percentage points. With one exception, the results did not differ for uninsured adults by sex, race/ethnicity, income, employment status, or presence of diabetes or hypertension. For cholesterol testing, the gap between the continuously uninsured and the insured groups was reduced significantly more among those with hypertension or diabetes, from 37 percentage points to 8 percentage points (a 29 percentage point difference), than among adults without either condition, who experienced a drop of only 8 percentage points. Patients with hypertension or diabetes face an increased risk of heart disease or stroke, so they are most likely to benefit from cholesterol testing and treatment. “The marked increases in the use of mammography and cholesterol testing show distinct benefits for previously uninsured adults who gain Medicare coverage,” said Dr. Ayanian, one of the authors of the study and a researcher at Harvard Medical School. "Extending Medicare coverage to these adults before age 65 has the potential to save many lives through prevention or earlier detection and treatment of major medical conditions such as cancer or heart disease."