Oct. 30 (UPI) — A study in Britain found no benefits to prescribing drugs for patients with low-risk mild hypertension, contrary to U.S. medical groups’ new guidelines.
Researchers from the University of Oxford, Cambridge University and the University of Birmingham came to that conclusion after studying the records of 38,286 patients collected over 15 years. The findings were published Monday in Journal of the American Medical Association Internal Medicine.
Blood pressure is the force of blood pushing against blood vessel walls. High blood pressure, or hypertension, is a major risk factor for cardiovascular disease and is the leading cause of mortality worldwide.
It is measured in millimeters of mercury, based on the systolic pressure, or the pressure when ventricular contraction occurs — this is the top number — and diastolic pressure, which is the pressure in blood vessels between heart beats — which is the lower number.
A normal blood pressure is considered a systolic of less than 120 and diastolic of less than 80. The considering for high blood pressure, however, was lowered in 2017.
Last November, researchers at the American College of Cardiology and American Heart Association jointly recommend that pharmacologic treatment to be initiated in high-risk patients with a blood pressure of 130/80 mm Hg or higher. This lowered the former recommendation that patients with pressure at 140/90 start treatment.
“We found that, contrary to the latest guideline recommendations, there was no evidence of any benefit to treating patients with low-risk mild hypertension,” study leader James Sheppard, from Oxford University’s Nuffield Department of Primary Care Health Sciences, said in an Oxford press release. “This suggests that doctors should be cautious when considering hypertension treatment in this group and we would therefore encourage a conversation between a patient and their doctor to decide the best way to treat the condition.”
He noted that younger patients may prefer to change their lifestyle to reduce their blood pressure, rather than taking antihypertensive drugs.
“Given that we found tangible evidence of the potential harm of treating people with mild hypertension, and no evidence of benefit, this study does raise questions over the value of initiating drug treatment in such patients,” said Dr. Jonathan Mant, head of the Primary Care Unit at the University of Cambridge.
Researchers analyzed data on 19,143 people aged 18-74 that was collected between 1998 and 2015. None of the patients had yet been treated for high blood pressure. These people were compared with an equal number of patients who went on to be treated with antihypertensive medication. The median follow-up was 5.8 years.
Researchers report that they found no benefit of drug use and no lower risk of heart attack or stroke.
But researchers found evidence of an increased risk of adverse events over the follow-up period of five to six years, including hypotension, which is low blood pressure, as well as fainting or kidney damage.
There were 1,641 deaths during the follow-up period, including 4.08 percent among the control group and 4.49 percent in the treatment group.
“Being an observational study, our data should be interpreted with caution since these studies can sometimes give biased results,” Sheppard said. “To ensure future guideline recommendations for treating low-risk mild hypertension are based on the best-quality evidence, large-scale clinical trials are now needed.”