A small device that delivers gentle electrical pulses through the ear could offer a new approach to treating stubborn high blood pressure. In a clinical trial led by researchers at Queen Mary University of London, the technology was found to be safe, well-tolerated and convenient for patients to use at home.
Although the treatment did not significantly reduce blood pressure compared to a placebo device in all participants, researchers observed encouraging results in patients with more severe hypertension. The findings suggest that stimulating nerves in the ear could potentially help some people whose blood pressure remains high despite taking medication.
Results are from the SCRATCH-HTN trial, published in Hypertensiona journal of the American Heart Association. The researchers emphasize that larger studies are needed to determine whether the approach can provide significant benefits and which patients might respond best to it.
How Auricular Nerve Stimulation Could Lower Blood Pressure
The experimental treatment uses a technique called transcutaneous autonomic neuromodulation (tAN), which aims to influence the autonomic nervous system. This network of nerves automatically controls essential bodily functions, including heart rate, digestion, and blood pressure.
By transmitting mild electrical signals to nerves in the ear, researchers hope to influence the body’s natural blood pressure regulation mechanisms without requiring an invasive procedure.
The portable device, developed by Afferent Medical Solutions, uses two small clips positioned on the tragus, the small flap of cartilage located just in front of the ear canal. These clips deliver gentle electrical stimulation, allowing patients to administer the treatment themselves without visiting a clinic.
A clinical trial tests the device in 63 patients
The clinical trial, funded by the National Institute for Health and Care Research (NIHR), involved 63 people with uncontrolled hypertension. All participants were already taking at least one medication to lower their blood pressure, but their results remained above recommended levels.
The researchers randomly divided the participants into two groups. One received active nerve stimulation, while the other used a dummy device designed to serve as a comparison. This approach helped investigators assess whether electrical stimulation produced benefits beyond those associated with use of the device itself.
Participants used their assigned devices for 30 minutes per day during the first two weeks. For the next 10 weeks, they reduced their sessions to once a week.
Results showed the treatment was safe and generally comfortable for participants. Most also followed the prescribed schedule, suggesting the technology could be practical for regular use at home.
However, when the researchers compared blood pressure changes across the entire study population, they found no statistically significant differences between patients receiving active stimulation and those using the sham device.
Promising results in patients with severe hypertension
Despite the lack of a significant overall benefit, the researchers identified a potentially important outcome among participants who started the trial with more severe hypertension.
An analysis of prespecified subgroups, meaning the researchers planned this comparison before examining the results, found a greater reduction in blood pressure in these patients when they received active nerve stimulation rather than the dummy treatment.
This finding raises the possibility that this technique might work better in people whose blood pressure is particularly difficult to control. However, the trial was relatively small and subgroup results need to be confirmed in larger studies before conclusions can be drawn about its effectiveness.
Dr Ajay Gupta, Chief Researcher, Clinical Reader at Queen Mary University of London and Consultant Physician at Barts Health NHS Trust, said:
“This is an exciting technology, highly acceptable to patients, which could ultimately provide a low-cost, scalable solution for millions of people.” Although the trial did not reach significance in the large unselected group, those with more severe hypertension showed a marked reduction in blood pressure in the active group compared to the sham group.
“As the first and most in-depth study of its kind, it opens the door to important new research directions that could help us understand whether non-invasive neuromodulation can benefit particular groups of patients with uncontrolled hypertension.”
A potential new option for hard-to-control blood pressure
High blood pressure, also known as hypertension, is a major contributor to cardiovascular disease and increases the risk of heart attacks and strokes. This puts additional pressure on the blood vessels and heart, potentially causing serious damage over time.
Although medications help many patients manage their condition, a significant number continue to have blood pressure values above recommended goals even while receiving treatment.
This ongoing challenge has encouraged scientists to explore additional approaches that could complement existing therapies.
Stimulation of the auditory nerve is one of these possibilities. Because the device is small, does not require surgery and can be used at home, it could be a practical option if future research establishes that it reliably lowers blood pressure in some patients.
For now, the results represent a first step rather than proof of an effective new treatment. Researchers say larger clinical trials will be essential to confirm the encouraging results in patients with severe hypertension and identify which groups, if any, might benefit most from this approach.
Gn Health
