Study tracks regional variation in medication use

ST. LOUIS, Missouri (CNN) -- Prescription drug use patterns varied widely in 2000 depending on which region of the country a person lived in, according to a study released Tuesday.

Some of the most populous states -- including California, New York, Florida, and New Jersey -- have some of the lowest per capita rates of prescription drug use in the nation, according to a study by Express Scripts, a pharmacy benefits management company.

The rate in New York and California, for example, was 7.7 prescriptions a year for those served by the company's pharmacy benefit plans. Topping the list of per capita prescription drug use were Kentucky, West Virginia, and Ohio, where the rate was more than 11 prescriptions per year.

"Such wide regional variation adds an entirely new dimension to an already complex pharmacy landscape. We suspect the explanation lies in physician prescribing habits and the health status of a state's population, but consumer preferences may also play a role, said Barrett Toan, chief executive of Express Scripts.

The study was based on a randomly selected sample of 8.8 million of the 45 million Americans whose pharmaceutical needs the company manages. The findings were expected to be announced at a medical conference Tuesday in St. Louis.

Researchers were surprised by the findings, said Express Scripts researcher Brenda Motheral. "There were significant variations in the use of prescriptions across the country. More than anticipated," she said.

Other findings include:

* Higher rates of antidepressant use in Utah, Maine, Oregon and Washington.

* Higher rates of cardiovascular medication use in West Virginia, Kentucky, Tennessee, South Carolina, Mississippi and Louisiana.

* Higher rates of antidiabetic medication use in West Virginia, Texas, North Carolina, Utah and Ohio.

*Lower rates of antihyperlipidemic drug use in New Mexico, Colorado, Idaho, Alabama, Montana and California.

*Lower rates of asthma medication use in Mississippi, Arkansas, Louisiana and South Carolina.

* Lower rates of estrogen use among women in New Jersey, New York and Massachusetts.

Among children in the 5 to 14 age group, use of medications to treat attention deficit disorder varied by a factor of 3.3 across states in 2000. Louisiana had the highest prevalence of use, with South Carolina and Alabama rounding out the top three. Colorado, California and Nevada demonstrated the lowest prevalence of use.

"Our findings regarding ADHD medications highlight the controversy and uncertainty surrounding both the diagnosis and the use of psychostimulants in the treatment of ADHD in children," Motheral said.

The average wholesale price per prescription drug spending increased 16.2 percent over 2000 to $449.74 per members, the study found.

The average prescription cost increase was highest for children under age 10. Factors contributing to the cost increase -- from $28.25 to $33.23 -- were higher prices for existing products, use of more expensive products, stronger dosages and more units per prescription.