According to Michael Bihari, MD, summary from the Kaiser Family Foundation published Aug.2008: The Medicare Part D Coverage Gap: Costs and Consequences In 2007 .

Medication News - Friday August 22, 2008

3.4 million Medicare Part D plan enrollees reached a gap in their prescription drug coverage, according to a new report from the Kaiser Family Foundation. This gap - known as the "doughnut hole" - is the period during which people with a Medicare drug plan have to pay 100% of their drug costs, which is in 2008 is more than $2700.

The Kaiser study found that more than 25% of Part D enrollees who filled any prescriptions in 2007 reached the coverage gap. Enrollees with chronic conditions such as Alzheimer's disease, diabetes, and depression had a much higher risk of reaching the coverage gap.

Some enrollees who reach the coverage gap stop taking their medication. Looking at eight classes of medications prescribed for a variety of common health conditions, the researchers found that about 15% of Part D enrollees who reached the coverage gap stopped their medications. For example, 10% of Part D enrollees taking oral medication for the treatment of type 2 diabetes who reached the coverage gap stopped taking their medications. For a person with diabetes stopping medication for even a short period of time can cause serious and immediate health problems.

### Source: About.com