Out with the old drugs and in with the new! How is your doctor prescribing for you?
Imagine that you are a physician and your patient is a 55-year-old white male with high blood pressure. He has no other medical problems, is on no medications, and has completed a 1-year program of diet and exercise to control his condition, but his blood pressure remains elevated at 170/105 (140/90 is the definition of high blood pressure).
As his physician, you have to decide on a medication to prescribe him in order to lower his blood pressure. You have the following options to choose from:
Diuretics: Diuretics are medications that lower blood pressure by getting rid of excess fluid in your body, making it easier for your heart to pump. They were first introduced in the 1950s.
Beta-blockers: Beta-blockers are medications that lower blood pressure by helping the heart to relax and pump more effectively, and by also reducing heart rate. They were first introduced in the 1960s.
ACE inhibitors: Angiotensin converting enzyme (ACE) inhibitors are medications that lower blood pressure by widening blood vessels and increasing blood flow. They were first introduced in 1981.
Calcium channel blockers: Calcium channel blockers are medications that lower blood pressure by relaxing blood vessels, reducing the heart's workload, and increasing the amount of blood and oxygen that reach the heart. They were also first introduced in 1981.
What type of medication would you prescribe this patient?
- A diuretic
- A beta-blocker
- An ACE inhibitor
- A calcium channel blocker
How do you compare to the physicians surveyed?
Of the physicians surveyed, 18% chose the same medication as you did. 38% chose an ACE inhibitor, 29% chose a beta-blocker, and 11% chose a calcium channel blocker. Most physicians chose an ACE inhibitor, a newer type of medication, rather than beta-blockers or diuretics, which are older types of medication.
Why is this important? When asked how they made their decision, the majority of physicians believed that diuretics were less effective and that beta-blockers were less likely to be tolerated by a patient's body than the other medications. However, a number of important studies have shown that beta-blockers and diuretics are as effective at lowering blood pressure as newer medications like ACE inhibitors and calcium channel blockers. Studies have also shown that beta-blockers and diuretics are equally or even better tolerated than the newer types of medications. Yet, the use of beta-blockers and diuretics has declined steadily in the past 15 years in favor of the newer and more expensive types of medications.
Why do physicians believe these things when the studies say otherwise?
The answer to this question is not fully known. One possibility is that physicians may be prescribing newer medications because these are the medications actively promoted by pharmaceutical companies. By providing free samples of the newer medications for physicians to give to patients, these companies may be influencing which medications physicians actually decide to prescribe. To test this possibility, after physicians had decided between diuretics, beta-blockers, ACE inhibitors, and calcium channel blockers, they were asked if they ever provide their patients with free medication samples from these companies to treat their high blood pressure. It was found that physicians who used free samples were more likely to believe that ACE inhibitors are more effective. This isn't proof that physicians are influenced by pharmaceutical companies when prescribing medication for high blood pressure, but it does urge us to seriously consider if physicians may need to be re-educated about the effectiveness and tolerability of beta-blockers and diuretics.
For more information see:
Ubel, PA, Jepson, C, Asch, DA. Misperceptions about beta-blockers and diuretics. Journal of General Internal Medicine, 18, 977-983. 2003.