Kaiser analysis of impact of Part D "doughnut hole": An analysis from the Kaiser Foundation has quantified for the first time the number of Medicare Part D plan enrollees in 2007 who reached a gap in their medication coverage known as the "doughnut hole," when they must pay full prescription costs. Claims data for about 50% of all U.S. retail prescriptions were analyzed, with a focus on Part D enrollees taking drugs in eight classes to treat chronic conditions: Alzheimer's disease, high cholesterol, depression, diabetes, gastroesophageal reflux disease, heart failure, hypertension, and osteoporosis. The analysis found that one in four (26%) Part D enrollees who filled any prescriptions in 2007 reached the coverage gap; only 15% of those reaching the gap had sufficient additional drug spending to receive catastrophic coverage, at which point the plan pays 95% of drug costs. Among all Part D enrollees, 18% filled prescriptions for antidepressants, and 35% of this group reached the gap; 10% later qualified for catastrophic coverage. Antidepressants ranked fourth—behind Alzheimer's treatments, oral antidiabetic drugs, and proton pump inhibitors—in terms of the percentage of users who reached the coverage gap. Of those taking antidepressants who reached the gap, 15% stopped taking the medication, 1% reduced medication use, and 6% switched medications. Among enrollees who reached the gap but not catastrophic coverage, average out-of-pocket spending increased from $104 per month before the gap to $196 per month during the gap. The 37-page report, The Medicare Part D Coverage Gap: Costs and Consequences in 2007, is available on the Kaiser Web site at www.kff.org/medicare.