Older Americans may be getting used to the new Medicare Part D prescription drug program.

About 29% of the heaviest prescription users who belong to the program say they have had “major problems” with the Medicare drug program, but 59% say the program is working well or could work well with minor changes, according to researchers at the Henry J. Kaiser Family Foundation, Menlo Park, Calif.

Researchers at the foundation published those results in a summary of a June survey of 1,585 U.S. adults ages 65 and over.

Sicker patients with more complicated health problems may run into problems with a new program faster than individuals who have little need for program benefits.

But 49% of Medicare program members who take 6 or more prescriptions daily said they have had no problems with the program, and 17% have had only minor problems, researchers report.

Although 29% of those heavy prescription users have had major problems, only 18% of the program members who are taking 4 or 5 prescriptions daily said they have had major problems, the researchers say.

Only 12% of participants said they had left pharmacies without a prescription because the drug was not covered or they could not afford the drug, but 15% of participants said they had paid unexpected costs, and 6% said they had run into billing mistakes.

About 27% of participants said the drug program is not working and needs major changes, but 24% said the program is working well and 35% said the program could work well with minor changes.

A trend line chart shows that older Americans’ favorable impressions of the drug program are now close to the high they reached in August 2005, while unfavorable impressions have dropped to the lowest level since Kaiser Foundation researchers began tracking consumer attitudes toward the program in February 2004.

About 9% of seniors interviewed said “health care overall” will be the single most important issue in their vote for Congress this fall, and 8% said “prescription drug benefits for the elderly” will be the single most important issue, researchers report.

Pluralities of 12% to 14% identified “the situation in Iraq,” the “U.S. campaign against terrorism,” or “gas prices” as the single most important issue.