Hypertension or high blood pressure, is one of the major global causes of death. It can lead to strokes, as well as heart, brain, and kidney disease. It is often referred to as the “silent killer,” as an estimated 46% of people who have hypertension do not know they have it.
Healthy lifestyle and diet changes can help manage the condition and may be aided by numerous hypertension drugs that are sometimes prescribed in combination. For many people, this is sufficient. For some, however, blood pressure remains persistently high.
A new meta-analysis finds that using therapeutic ultrasound to calm kidney-nerve hyperactivity significantly lowered blood pressure among the 506 people with hypertension in three randomized clinical trials.
It is not entirely clear what causes hypertension, though experts suspect it may be a combination of genetic and lifestyle factors, as well as aging and other mechanisms.
Hypertension in middle age is frequently associated with overactive nerves in the kidneys, which may promote high blood pressure in several ways. It may trigger water and salt retention, and release hormones that increase blood pressure.
While there are various types of drugs that treat hypertension, none specifically target this renal overactivity. The “renal denervation” ultrasound technique explored in the new study, which calms overactive nerves in the kidneys, therefore offers physicians an additional tool with which to help patients remain healthy.
The study was conducted by researchers from Columbia University, New York City, and Université de Paris, France. It appears in JAMA Cardiology.
How blood pressure is measured
Blood pressure is measured in millimeters of mercury, or mmHG. This is because the first accurate blood pressure gauges relied on mercury, as do some modern devices.
Blood pressure is reported as two values, often shown one above the other, or one to the left of the other. The first value is systolic blood pressure, the pressure the heart exerts when it is pumping blood. The second, diastolic, value indicates the pressure in arteries between heartbeats.
The American Heart Association considers a systolic blood pressure of less than 120 mmHG over a diastolic pressure of less than 80 mmHG to be healthy. Stage 1 hypertension occurs with a reading of 130-139/ 80-89 mmHG. Higher readings signify stage 2 hypertension.
Overall, the new study found that renal denervation lowered participants’ blood pressure significantly, by 5 to 10 mmHG, with an average reduction of 8.5 mmHG.
Written By: Robby Berman – Fact Checked by Hannah Flynn
Medical News Today: Hypertension: Ultrasound device could lower blood pressure significantly
