Sunday, March 11, 2007

Hypertension 41: The Therapeutics Initiative

My wife, a women’s health advocate, brought the Therapeutics Initiative, from the University of British Columbia, to my attention. The current issue of the “Therapeutics Letter” ( addresses how physicians should make decisions, with their patients, about using prescription medications to treat mild Hypertension.

The Therapeutics Initiative believes that “health care professionals should try to practice evidence based medicine and shared-informed decision making whenever possible.” Who would disagree with that?

Read on, though it does get a bit technical.

The specific question the Therapeutics Initiative addressed: “How much does antihypertensive drug therapy as compared to placebo or no treatment change mortality and morbidity in randomized controlled trials of men with BP in the range of 140-160/90-100 mmHg?”

It quotes the results of five randomized clinical trials of people with mild hypertension, comparing regular medical treatments versus placebos. “In these trials 23,000 people were studied, 54% male, average age 51 years, the average baseline BP was 160/98 mmHg and most subjects had no evidence of cardiovascular disease. The first-line drugs studied were thiazides in all 5 RCTs, the only exception being one RCT which also had a beta blocker arm. The average duration of follow-up was 5 years.”

The results from the five trials? “Removing the first-line beta blocker arm did not materially change the estimates…. In the 5 trials there was no benefit in terms of total mortality, but there was a reduction in total strokes and heart attacks from 4% to 3.2%. [not a huge difference, eh?] The magnitude of the absolute reduction was 0.8%, meaning that 125 people like [the patient in question] would have to be treated for 5 years to prevent one heart attack or stroke. On the harm side there was a 9% absolute increase in withdrawals due to adverse effects with drug treatment as compared to placebo. That means that for every 11 people treated one would stop the drug because of a side effect. That side effect would resolve after the drug was stopped.”


Of course, the study did not cover everything. For example, there are other harmful effects of Hypertension than strokes and heart attacks. The studies covered only people with mild Hypertension. And there was no indication whether the damaging effects of Hypertension would increase over time—maybe there was no reduction at a lower age, but after ten years of non-treatment, perhaps the statistics would change.

But as a person who only has “mild” Hypertension after taking three strong prescription medications each morning, the information in the Therapeutics Initiative certainly had resonance for me. I had always wondered whether these prescription medications, which had strong negative side effects and which cost around $250 per month, actually did any good. “Common” or “mainstream” medical practice says yes.

Actual facts appear to say, at the very least, not really.

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