There’s no doubt that managing high blood pressure is an important step in lowering an individual’s risk of developing cardiovascular disease. However, new research published in the American Journal of Preventive Medicine suggests that patients taking prescription drugs to treat hypertension may experience periods of low blood pressure which raises their risk of injury as a result of falling or fainting.
Unusually low blood pressure is characterized as a systolic blood pressure below 110mmHg. Since the American Heart Association and the American College of Cardiology recently lowered the definition of hypertension from a systolic blood pressure of 140 down to 130, the findings from the current study have even more important implications on how patients are treated.
“Efforts to reduce blood pressures for patients with hypertension are an important factor in reducing the risk of heart attack and stroke,” said Dr. John J. Sim, a nephrologist with the Kaiser Permanente Los Angeles Medical Center, and lead author on the study. “But our study shows that attaining a lower blood pressure could create a subpopulation of patients whose blood pressures may go too low, which can pose risk for serious falls and fainting.
In analyzing the electronic health records of over 475,000 patients on hypertension medication who visited Southern California care centers that are part of the Kaiser Permanente health network over a one-year period, the researchers found that patients who experienced blood pressures of less than 110mmHg were more likely to suffer fainting spells and serious falls. These events resulted in patients visiting the emergency department or being admitted to the hospital as an inpatient.
Sim and his team found that 27 percent of patients who were being treated for hypertension had a systolic blood pressure that was below 110mmHg during at least one doctor’s visit. For three percent of patients, their average blood pressure reading over the 12-month study period was considered to be unusually low. These low blood pressure readings translated to a two-fold higher risk of fainting and falls for these patients.
“Physicians considering lower blood pressure targets for their patients should weigh the risks and benefits of aggressive blood-pressure lowering on an individual basis, especially in older patients,” said Sim.
Since older patients are more likely to experience sudden drops in blood pressure, often when they stand up, Sim recommends looking out for these symptoms before they’re put on hypertension medications. In addition, physicians should pay attention to signs of acute illness which could make a patient unsuitable for therapies which lower blood pressure.
In a statement regarding the change in the definition of hypertension, Dr. Paul K. Whelton, lead author of the guidelines, defended the decision by highlighting how it will benefit patients at risk of cardiovascular disease.
“You’ve already doubled your risk of cardiovascular complications compared to those with a normal level of blood pressure,” said Whelton. “We want to be straight with people – if you already have a doubling of risk, you need to know about it. It doesn’t mean you need medication, but it’s a yellow light that you need to be lowering your blood pressure, mainly with non-drug approaches.”