Doctors influenced to prescribe pricier, riskier blood pressure meds

Even though research has shown inexpensive treatments for high blood pressure are just as effective as pricey new drugs – and have fewer and less dangerous side effects – many doctors continue to prescribe the new drugs, according to a new study by a University of Michigan Health System physician.

Part of the reason is that they are influenced by drug sale reps who bombard them with marketing literature, samples, and other incentives.

“These new, more expensive medications are being more heavily promoted by the drug companies, and one way or another that information influences how people perceive the drug’s effectiveness,” said study author Peter A. Ubel, M.D., associate professor of internal medicine at the U-M Medical School and director of the U-M Health System’s Program for Improving Health Care Decisions.

The study, published in the December issue of the Journal of General Internal Medicine, presented a hypothetical patient whose blood pressure was 170/105 (anything higher than 140/90 is considered abnormal). The patient had tried to control his blood pressure for a year using diet and exercise but it remained high. He has no other medical problems. Doctors were asked to estimate the effectiveness in this situation of ACE inhibitors, beta-blockers, calcium channel blockers and diuretics. They were also asked what medication they would initially prescribe for this patient.

Despite numerous clinical trials that have shown diuretics and beta-blockers to be equally effective in treating uncomplicated high blood pressure, the doctors surveyed rated diuretics significantly less effective than the other three drugs and felt beta-blockers were more likely to cause side effects.

Doctors were most likely to recommend ACE inhibitors as their first treatment choice.

ACE inhibitors are recommended only when diabetes or heart disease accompanies hypertension, Ubel noted. For the hypothetical patient, there would be no advantage to taking ACE inhibitors over diuretics or beta-blockers. In fact, ACE inhibitors tend to have more side effects than diuretics or beta-blockers. They’re also more expensive, which could drive up the patient’s bill at the drug store – or ultimately drive up insurance costs.

Doctors who recommended ACE inhibitors or calcium channel blockers were much more likely to have been given free drug samples by the pharmaceutical companies.  Pharmaceutical representatives often visit doctors’ offices to introduce them to the latest drugs and provide free samples. Many drug companies also sponsor continuing medical education courses, which are required for doctors to maintain their certification.

“The industry influence is pervasive,” said Ubel, who is also a research investigator at the Ann Arbor Veterans Administration Health Center. “I think a lot of physicians do rely on sales representatives to tell them about the latest medications out there. How else do you find this out? It is very hard to keep up on the medical literature. Doctors feel it’s an educational visit, but the sales reps hand out samples.”

The University of Michigan Hospitals and Health Centers prohibits distributing drug samples to patients. “It may seem like the doctor’s helping patients get more affordable medicine, but it’s not a lifetime supply. After the free samples run out, the patient is left to pay for a more expensive drug,” Ubel added.

SOURCE: “Misperceptions About -Blockers and Diuretics. A National Survey of Primary Care Physicians,” by Peter A. Ubel, Christopher Jepson, David A. Asch. Journal of General Internal Medicine, Dec. 2003.