One in seven nonelderly Americans skipped a prescription drug in 2007 because of costs, a jump from one in 10 in 2003, according to a study by the Center for Studying Health System Change (HSC). That translates into roughly 36.1 million working-age people and children, an increase of 11.7 million people from 2003.

Both the rising cost of medications and less generous drug coverage in insurance plans (meaning more out-of-pocket expenses) likely contributed to the increase, and as might be expected, the greatest unmet needs were among low-income people, those with chronic diseases, and the uninsured. In fact slightly more than a third of uninsured working age Americans, reported trouble getting prescription drugs, up from 26 percent in 2003.

But the problem is growing even among the insured, rising from 8.7 to 10.7 percent of Americans under age 65 with employer-sponsored insurance.

"The number of Americans who cannot afford prescription medications is likely to grow as the economy continues to decline and the ranks of the uninsured grow," said Laurie E. Felland, M.S. an HSC senior health researcher and coauthor of the study, More Nonelderly Americans Face Problems Affording Prescription Drugs.

Nor is the outlook particularly rosy. Even though more generics are coming on the market, the HSC report cited predictions by pharmaceutical industry analysts that spending growth for speciality drugs will increase about 20 percent a year in the near future. Those drugs are gaining importance in treatment regimens (although we hope that with comparative effectiveness research, we get better insight into which of these new drugs are really better than older ones.) The economic decline of course also makes it harder for people to afford their medications.

The data came from HSC's 2007 Health Tracking Household Survey, a nationally representative survey containing information on 10,400 working-age adults (ages 19-64) and 2,600 children. The survey had a 43 percent response rate. The study was funded by the Robert Wood Johnson Foundation.