FRIDAY, March 5, 2004 (HealthDayNews) -- Many Americans pay too much for the drugs they take to control high blood pressure, in part because doctors prescribe higher-priced brand name products rather than generics that could do the job just as well, a new study finds.
"We looked at the total cost of drugs for treatment of hypertension," the formal medical name for high blood pressure, says Dr. Randall Scott Stafford, who reported the results of his study March 4 at the American Heart Association's Annual Conference on Cardiovascular Disease, Epidemiology and Prevention in San Francisco. "We were interested in what played into the increase in cost of this form of therapy."
In 2002, Americans spent $12 billion on prescription drugs for high blood pressure, says Stafford, who is an assistant professor of medicine at the Stanford University Prevention Research Center. While precise cost comparisons are difficult to make, that appears to be slightly more than double what was spent in 1990, he says.
His study includes information on 17,318 visits to doctors' offices for treatment of high blood pressure in 1990, 21,885 visits in 2002, and cost information from 20,000 pharmacies.
Four factors contributed to the increase in total cost, Stafford says. Many more people are taking drugs (although the heart association estimates that only a third of people with high blood pressure are getting adequate treatment), many patients are taking more than one drug, drug prices in general have gone up, and doctors are selecting more expensive drugs.
"When we analyzed the data, we found that the degree to which selection impacted on cost was the biggest factor," Stafford says.
Use of more than one drug for blood pressure -- a tactic recommended by hypertension experts -- accounts for 8 percent of the cost increase, he says. Growth in the number of people taking the drugs -- a welcome phenomenon -- accounts for 17 percent. Overall drug price increases accounts for 29 percent of the increase.
But more than a third of the increase was due to physicians prescribing higher-price drugs over cheaper alternatives, he says.
Specifically, Stafford pinpoints three classes of drugs. Two are angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), newer and higher-cost medications. The third is diuretics, older drugs that are available in cheaper generic versions.
A month's supply of a diuretic costs about $9, compared to $44 for an ACE inhibitor and $56 for an ARB, Stafford says. And while current guidelines call for use of a diuretic as first-line treatment, prescriptions for these drugs decreased by 50 percent between 1990 and 2002, while use of both ARBs and ACE inhibitors increased.
It's entirely possible that the increased usd of the more expensive dugs is justified because of the needs of individual patients, Stafford says. "The data we looked at do not enable us to say if the right ones or wrong ones are being prescribed based on clinical characteristics of patients," he says.
But there are nonmedical reasons for the choices being made, Stafford says. One is that the newer, more expensive drugs get more publicity because they are used in trials whose results are heralded in medical journals.
Marketing tactics of drug companies also are a factor, he says: "Pharmaceutical promotion clearly has an impact on medical practice."
Anyone taking medication for high blood pressure should be aware of the guidelines, which support use of drugs such as diuretics that are available in inexpensive versions, Stafford says.
"If a diuretic is not being prescribed, there should be a good reason for it," he says.
To which Dr. Daniel Jones, vice chancellor for health affairs at the University of Mississippi and a spokesman for the American Heart Association, adds a footnote: "For most patients, the type of drug selected is not as important as getting the blood pressure lowered to the right level."