Are you taking drugs for mild hypertension, yet you’ve not had a heart attack, stroke, or a diagnosis of heart disease? A new review of all studies that followed people who fit this description could not find a benefit to drug treatment. Astounding — when you consider that half the people currently on blood pressure-lowering drugs have only mild hypertension. Not incidentally, the threshold for mild hypertension has been lowered considerably over the years, thus making more and more of us into drug customers.
The review was published this week by the Cochrane Collaboration, an international organization that evaluates medical research. It’s the first hard look that any independent team of researchers has directed at the evidence for prescribing drug for mild hypertension. The best of all available research boiled down to four clinical trials with a combined total of nearly 9,000 participants who had mild hypertension. It should be noted here that these are old studies … from an era when mild hypertension was 140-159/ 90-99 mmHg. All were randomly assigned to take a drug or a placebo every day for five years. While these four studies may be the best available, the reviewers found that they left a lot to be desired. Only one, for example, kept track of the number of participants who dropped out of the study due to adverse effects.
Here’s the Cochrane review conclusion: “Available data from the limited number of available trials and participants showed no difference between treated and untreated individuals in heart attack, stroke, and death. About 9% of patients treated with drugs discontinued treatment due to adverse effects. Therefore, the benefits and harms of antihypertensive drug therapy in this population need to be investigated by further research.” The reviewers acknowledged that withdrawals may not be this high with today’s lower doses of thiazides and beta-blockers (two most common anti-hypertensive drug classes).
“We just assumed that there must be benefits to treating most people with mild hypertension and that the benefits were greater than the harms,” said James Wright, MD, co-author of the Cochrane review, referring to conventional medical wisdom. In a telephone interview, Dr. Wright described his own reaction to what he and his co-authors found. “It was shocking to me, and it changes the way I approach my patients with mild hypertension,” he said. “I tell them that there is no proven benefit to continuing treatment. Some say, ‘Fine I’ll go off the drugs.’ Others say, ‘I’ll stay on the drugs anyway.’” What? Some of your patients would actually stay on a drug after hearing that it provides no benefit! What about the unanswered questions about harm? “For sure, there will be harm,” he responded. “The idea that any drug is without serious adverse effects is just wrong.”
Dr. Wright, who is a professor of Medicine at the University of British Columbia, Vancouver, explained that the four trials in this review looked only for effectiveness and not serious adverse effects, and none were funded by drug companies. Today, most drug trials are funded by industry, and all are now required to collect information about serious adverse effects. Unfortunately, he said, many of these industry-funded clinical trials withhold findings that are unfavorable to their products. Too often, only some—-but not all—serious adverse effects are reported.
The conclusion of the Cochrane review calls into question the hypertension guideline recommendations in the US, Canada and Europe. These guideline groups have recommended treatment of all adults with a blood pressure of more than 140/90 mmHg, yet the reviewers found no proven benefit to treating people with blood pressures under 159/99. The time is right for a rethink, as the reviewers observed, “The decision to treat people with mild hypertension has important consequences for both the patients (e.g. adverse drug effects, lifetime of drug therapy, cost of treatment, etc.) and any third party payer (e.g. high cost of drugs, physician services, laboratory tests, etc.).”
-Despite the title of the new Cochrane review — ”Benefits of drugs for mild hypertension are unclear” — all the study participants actually had what is considered to be moderate hypertension by today’s definition (140-159/90-99). If this describes you and you are currently taking anti-hypertenisve drugs, print out this abstract and discuss it with your doctor. Disclosure: I am an unpaid contributor to the Cochrane Collaboration, which describes itself as ”an international, independent, not-for-profit organisation of over 28,000 contributors from more than 100 countries, dedicated to making up-to-date, accurate information about the effects of health care readily available worldwide.”
-There are non-drug treatments for hypertension (e.g. diet, exercise, stress management, etc.). The Cochrane reviewers say that many people with mild hypertension might give them a try, if they knew the uncertainties of drug therapy.
-Dr. Wright is a co-author of an earlier Cochrane review that found no benefit for drug treatment that lowers blood pressure below 140/90. Read this 2009 interview with him.
-Here’s a 2009 post that presents a case for taking anti-hypertensive drugs whether or not you have high blood pressure. Small doses are key to minimizing adverse effects. Learn your chances of having a stroke, heart attack or heart failure, as well as the drug treatment’s reduction of each.
- Read “Treatment guidelines and conflict of interest“ which describes the drug industry connections of experts who set treatment standards.
-This is a trip-down-memory-lane historical post “Prehypertension—How real is this new “disease?” from 2003, when 120-139/80-89 was declared prehypertension. This new information about the lack of proven benefit for treating mild hypertension makes the concept and treatment of prehypertension even more absurd.
Maryann Napoli, Center for Medical Consumers©