A new study by the Johns Hopkins Bloomberg School of Public Health and the University of Illinois at Chicago finds that Medicare Part D prescription coverage significantly reduced hospital admissions and program expenditures totaling $1.5 billion annually. In the largest and most rigorous impact analysis of Medicare Part D to date, researchers found that gaining prescription drug insurance through Medicare Part D reduced hospitalizations by 8 percent, decreased annual Medicare expenditures for hospitalization by 7 percent and reduced hospital charges associated with hospitalization by 12 percent during the program’s first four years.