Ear-nerve stimulation trial finds no significant overall blood-pressure benefit

A noninvasive device that stimulates nerves through the ear did not significantly improve blood-pressure reduction compared with sham treatment across the overall population of a small randomized trial, according to a September 28 update from Queen Mary University of London. The finding limits claims that the approach is ready to help patients whose hypertension remains uncontrolled despite medication.

The university highlighted encouraging tolerability and a possible benefit among participants with more severe hypertension. Those observations support further investigation, but they leave the central clinical question unresolved: whether the device reliably improves blood-pressure control beyond the effects seen with a sham procedure.

### What the trial tested

SCRATCH-HTN enrolled 63 people with elevated blood pressure despite antihypertensive treatment. Its published protocol describes a phase 2a, double-blind, randomized trial assigning participants to active stimulation or sham treatment in a two-to-one ratio.

The technique, called transcutaneous autonomic neuromodulation, aims to influence the nervous system’s regulation of blood pressure. The handheld device delivers electrical stimulation through clips attached to the tragus, the small cartilage projection at the front of the ear. Participants used the equipment at home during a 12-week treatment period.

The protocol specified change in daytime systolic blood pressure measured by ambulatory monitoring at three months as the primary endpoint. Systolic pressure is the upper number in a blood-pressure reading. Other planned measures included around-the-clock and clinic blood pressure, heart-rate variability, sleep and quality of life.

This design matters because a randomized sham comparison tests whether an intervention adds benefit beyond changes associated with participating in a study. A reduction from a participant’s starting blood pressure alone cannot establish that the device caused the improvement.

### A subgroup signal needs confirmation

Queen Mary reported no significant overall difference between active and sham treatment, while describing a greater reduction in a prespecified subgroup with more severe hypertension at baseline.

Earlier conference coverage on the German cardiology portal Herzmedizin provides useful context. Its account of the March 2026 American College of Cardiology presentation likewise reported no significant overall blood-pressure advantage. It noted that the subgroup with baseline systolic pressure of at least 160 mmHg contained only 16 participants: 10 receiving active treatment and six receiving sham treatment.

That small comparison cannot establish a dependable treatment effect for the wider population with severe hypertension. Prespecifying an analysis strengthens its interpretability, but does not remove uncertainty from a small sample. Confirmation would require a larger trial designed to test that population directly.

The conference account also reported that blinding was imperfect, with participants’ perceptions of their treatment assignment differing between groups. That complicates interpretation of subjective outcomes and reinforces the value of objective measurements.

### What this means for prevention

Hypertension is relevant to healthspan because it contributes to cardiovascular disease, including heart attack and stroke. A practical intervention that improves sustained control could therefore matter well beyond a blood-pressure reading. This trial, however, does not establish fewer cardiovascular events, longer survival or preserved independence.

The university’s description of good tolerability is an early feasibility finding. A study of 63 participants over three months cannot settle uncommon adverse effects or long-term safety.

The chronology also matters: the September 28 announcement discusses publication in Hypertension, while results had already been presented at a March conference. The latest update brings renewed attention to an existing clinical signal; it does not represent the first disclosure of benefit. The evidence currently supports additional targeted research, with no established overall efficacy advantage in this trial.