Since their initial release, the 2017 American College of Cardiology/American Heart Association guidelines have caused controversy. The guidelines recommended a lower threshold for diagnosis of hypertension, to a blood pressure of 130/80 mm Hg, down from 140/90 mm Hg. Under the new standard, 45.4% of American adults are estimated to have hypertension, an increase of 31 million currently with the diagnosis. Therefore, more than one-third (35.9%) of adults would require treatment for hypertension under the new guidelines.
An analysis in JAMA Cardiology estimated that if those diagnosed with hypertension under the new standard brought their blood pressure down to 130/80 mm Hg, roughly 610,000 cardiovascular events and 334,000 total deaths could be avoided.
Physician checks patient's blood pressure. (Source: 59th Medical Wing)
The benefit to the individual patients is not as clear. The analysis found that the new guidelines will also cause 6,000 new cases of hypotension and 79,000 acute kidney injury or failure events each year.
An accompanying editorial pointed out that 80% of individuals newly diagnosed with hypertension based on the changed guidelines would have no expected reduction in cardiovascular disease risk associated with lowering their blood pressure. Another 11% would reduce their five-year risk of a cardiovascular event by 1.4%.
For the four out of five patients newly considered hypertensive who would not benefit, the diagnosis is not a neutral event, as it poses some clear harms, according to the editorialists. A diagnosis of hypertension increases a patient’s risk of anxiety and depression compared to those with the same blood pressure who do not have the diagnosis, and may increase challenges associated with obtaining insurance. Those newly prescribed pharmacotherapy for hypertension or who have intensified treatment to reach the lower goals face other risks, the authors wrote. In the SPRINT trial, intensively treated patients had a 2% increase in serious adverse events such as hypotension, syncope, electrolyte abnormalities, acute kidney injury or acute renal failure.
The HOPE-3 trial found that a higher percentage of intensively treated patients permanently discontinued all blood pressure medications than in the placebo group. In addition, for every 125 patients treated with blood pressure lowering medications over the 5.6 years of the study, one person experienced a serious adverse drug effect, including symptomatic hypotension, dizziness or light-headedness.The authors advised physician not to label the approximately 25 million patients at low risk of cardiovascular disease as hypertensives, and not to recommend drug treatment for those who would be classified as having hypertension under the new guidelines. Instead, the authors recommended “physicians should continue to support healthy choices with regard to diet and physical activity regardless of whether the patient’s systolic [blood pressure] is above or below 130 mm Hg.” For the 3 million at higher risk of cardiovascular disease, the authors agreed that the treatment and better blood pressure control would provide benefit, while patients in between the two categories should be actively engaged in discussion of the incremental harms and benefits of beginning or intensifying therapy.