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September 13, 2015- By Steven E. Greer, MD
The mainstream press did its usual thing this week and covered in a sensational manner the NIH-conducted SPRINT study which supposedly discovered that aggressively lowering blood pressure to below 120 mm Hg systolic reduces stroke and death risks. The TV doctors, such as CBS’ John LaPook and Tara Narula, made no attempt to critically analyze the data. One wonders where they read anything but the press release.
The mainstream press called SPRINT a “lifesaving trial”. If healthy patients over 50 years of age took aggressive ant hypertension medications to lower their systolic blood pressure to 120 or below, then they reduced the risk of heart disease and death.
Wow. That does indeed seem like a landmark study.
The problem is that the study has not yet been published, and all we know about the results are what has been released by the NIH in the form of a press release. However, we do know that the study was stopped three years prematurely.
This is a show stopper. Once a study is stopped early, it makes the results highly unreliable. Kaplan curves almost always converge back together as time goes by. Stopping a study early artificially inflates efficacy, and has been a ploy used by the drug industry for decades to generate junk data to help with drug approvals.
The New York Times quoted Dr. Gary H. Gibbons, director of the NIH institute that conducted SPRINT, “This study provides potentially lifesaving information (so we stopped it early).”.
Also, the efficacy of the aggressive hypertension therapy was only expressed in the news in terms of relative risk. One article wrote, “In the Systolic Blood Pressure Intervention Trial (SPRINT), investigators report that treating high-risk hypertensive adults 50 years of age and older to a target of 120 mm Hg significantly reduced cardiovascular events by 30% and reduced all-cause mortality by nearly 25% when compared with patients treated to a target of 140 mm Hg.”
Relative risk is another classic statistical ploy used by investigators to hype the results of trials in press releases. Reducing mortality by 25% sounds impressive, but given the low absolute rate of death in this healthy population, the real clinical impact could be very small, or less than one percent of actual risk reduction.
What’s the harm in lowering blood pressure too much? Hypotension and syncope are the main risk. This increases the risk of fatal falls and hip fractures. It is also costly to senior citizens to take these medications.
Contradicting this new SPRINT study, a group of doctors appointed by the NIH performed a meta-analysis and concluded that western medicine was over treating hypertension. In a 2014 JAMA paper, they recommended raising the blood pressure targets, not lowering them to 120 as SPRINT does. They wrote, “There is strong evidence to support treating hypertensive persons aged 60 years or older to a BP goal of less than 150/90 mm Hg and hypertensive persons 30 through 59 years of age to a diastolic goal of less than 90 mm Hg; however, there is insufficient evidence in hypertensive persons younger than 60 years for a systolic goal, or in those younger than 30 years for a diastolic goal, so the panel recommends a BP of less than 140/90 mm Hg for those groups based on expert opinion.”
The American Heart Association, which is mostly a lobbyist group for the cardiologists, disagreed with this 2014 JAMA article by the NIH team. The AHA wrote on September 11th, 2015, “Millions of Americans between the age of 60 and 80 could be confused over which blood pressure target to follow. A relaxed target for this age group (aiming only at bringing BP down to <150/90) would create a dangerous false-sense of security and take focus away from hypertension as a significant risk factor for heart disease and stroke. Although we recognize the enormous contribution of the NHLBI writing group that conducted a review of scientific evidence on hypertension, we don’t know why they decided to publish their report independently.”
This same ACC/AHA lobbyist group has issued other controversial “guidelines” that recommend aggressive medical therapy of disease. The 2013 ACC/AHA Guideline on the Assessment of Cardiovascular Risk developed a black-box “calculator” to spit out a formulaic one-size-fits-all guideline on who should be taking cholesterol-lowering drugs. It basically expanded the treatment population to most Americans, and ignored totally the controversy that chasing LDL cholesterol is a futile endeavor.
To be sure, there are tens of billions of dollars at stake to the pharmaceutical industry from this new SPRINT study, and the guidelines that it will shape. The drug companies directly fund the ACC and AHA and are also the largest advertisers to the mainstream press. The strong financial bias of “guidelines” cannot be ignored.