Peripheral nerve stimulation can reduce tremor symptoms

 

LOS ANGELES – A noninvasive peripheral nerve stimulation device has been shown to reduce symptoms of hand tremor among people with essential tremor, offering a possible alternative to invasive treatments such as deep-brain stimulation.

The neuromodulation device is worn on the wrist and uses electrodes to stimulate the radial and median nerves at a frequency that interrupts tremor. It contains sensors that measure tremor and adjust stimulation accordingly.

In two small, randomized, controlled studies presented at the annual meeting of the at the American Academy of Neurology, investigator Rajesh Pahwa, MD, of the University of Kansas in Kansas City, said that treatment with the device significantly reduced tremor symptoms, compared with sham treatment.

On April 26, the device’s manufacturer, Cala Health, announced in a news release that the U.S. Food and Drug Administration had granted marketing clearance for the device, based on this evidence.

For the first study, conducted in-clinic, 77 patients were randomized to either treatment (n = 40) or sham stimulation (n = 37) of the tremor-dominant hand. Tremor was measured before and immediately after a single 40-minute session of stimulation, and patients were asked to perform tasks in accordance with the Essential Tremor Rating Assessment Scale or TETRAS, a severity measure.

Subjects in the intervention group had about a 65% improvement in their upper-limb TETRAS scores, compared with those receiving sham treatment (P less than .01) and in total TETRAS performance (P less than .05).

Subjects also were tested in-clinic with props simulating common daily tasks such as unlocking a door with a key, holding a cup of tea, picking up loose change, or dialing a phone. Patients in the treatment group self-reported greater ease with all of these tasks after treatment, compared with the sham-treated group. Differences for some tasks reached statistical significance.

 

For the second study, conducted for 4 weeks, 61 patients were randomized to at-home treatment sessions with the neuromodulator or sham treatment for 40 minutes at least twice daily. Those receiving treatment (n = 31) saw greater reduction in tremor measured by the devices’ built-in sensors, compared with those assigned sham treatment (n = 15) or no treatment (n = 15). Nearly all sessions completed resulted in a measurable reduction of tremor.

In an interview at AAN, Manish Gupta of Cala Health, the device manufacturer, said that further studies are underway to assess the durability of the treatment.

“What we seem to be looking at is an on-demand therapy that delivers a transient relief,” Mr. Gupta said, adding that the devices could be used by patients at times when their tremor is most bothersome, or in anticipation of a task – such as dressing oneself or eating – that a tremor would affect the ability to perform.

“One thing we’re learning from clinicians is that tremor is variable within the patient, and it’s variable across patients,” Mr. Gupta said. “The same patient may find that they have less tremor a certain day or at certain times of the day. We don’t think this would replace deep-brain stimulation, which is a constant treatment effect, but it could serve for some patients as a step before it.”

Cala Health, the manufacturer, sponsored the study. One coauthor is an employee of Cala Health.

SOURCE: Pahwa R et al. AAN 2018, Abstract P4.474.

 

LOS ANGELES – A noninvasive peripheral nerve stimulation device has been shown to reduce symptoms of hand tremor among people with essential tremor, offering a possible alternative to invasive treatments such as deep-brain stimulation.

The neuromodulation device is worn on the wrist and uses electrodes to stimulate the radial and median nerves at a frequency that interrupts tremor. It contains sensors that measure tremor and adjust stimulation accordingly.

In two small, randomized, controlled studies presented at the annual meeting of the at the American Academy of Neurology, investigator Rajesh Pahwa, MD, of the University of Kansas in Kansas City, said that treatment with the device significantly reduced tremor symptoms, compared with sham treatment.

On April 26, the device’s manufacturer, Cala Health, announced in a news release that the U.S. Food and Drug Administration had granted marketing clearance for the device, based on this evidence.

For the first study, conducted in-clinic, 77 patients were randomized to either treatment (n = 40) or sham stimulation (n = 37) of the tremor-dominant hand. Tremor was measured before and immediately after a single 40-minute session of stimulation, and patients were asked to perform tasks in accordance with the Essential Tremor Rating Assessment Scale or TETRAS, a severity measure.

Subjects in the intervention group had about a 65% improvement in their upper-limb TETRAS scores, compared with those receiving sham treatment (P less than .01) and in total TETRAS performance (P less than .05).

Subjects also were tested in-clinic with props simulating common daily tasks such as unlocking a door with a key, holding a cup of tea, picking up loose change, or dialing a phone. Patients in the treatment group self-reported greater ease with all of these tasks after treatment, compared with the sham-treated group. Differences for some tasks reached statistical significance.

 

For the second study, conducted for 4 weeks, 61 patients were randomized to at-home treatment sessions with the neuromodulator or sham treatment for 40 minutes at least twice daily. Those receiving treatment (n = 31) saw greater reduction in tremor measured by the devices’ built-in sensors, compared with those assigned sham treatment (n = 15) or no treatment (n = 15). Nearly all sessions completed resulted in a measurable reduction of tremor.

In an interview at AAN, Manish Gupta of Cala Health, the device manufacturer, said that further studies are underway to assess the durability of the treatment.

“What we seem to be looking at is an on-demand therapy that delivers a transient relief,” Mr. Gupta said, adding that the devices could be used by patients at times when their tremor is most bothersome, or in anticipation of a task – such as dressing oneself or eating – that a tremor would affect the ability to perform.

“One thing we’re learning from clinicians is that tremor is variable within the patient, and it’s variable across patients,” Mr. Gupta said. “The same patient may find that they have less tremor a certain day or at certain times of the day. We don’t think this would replace deep-brain stimulation, which is a constant treatment effect, but it could serve for some patients as a step before it.”

Cala Health, the manufacturer, sponsored the study. One coauthor is an employee of Cala Health.

SOURCE: Pahwa R et al. AAN 2018, Abstract P4.474.

 

LOS ANGELES – A noninvasive peripheral nerve stimulation device has been shown to reduce symptoms of hand tremor among people with essential tremor, offering a possible alternative to invasive treatments such as deep-brain stimulation.

The neuromodulation device is worn on the wrist and uses electrodes to stimulate the radial and median nerves at a frequency that interrupts tremor. It contains sensors that measure tremor and adjust stimulation accordingly.

In two small, randomized, controlled studies presented at the annual meeting of the at the American Academy of Neurology, investigator Rajesh Pahwa, MD, of the University of Kansas in Kansas City, said that treatment with the device significantly reduced tremor symptoms, compared with sham treatment.

On April 26, the device’s manufacturer, Cala Health, announced in a news release that the U.S. Food and Drug Administration had granted marketing clearance for the device, based on this evidence.

For the first study, conducted in-clinic, 77 patients were randomized to either treatment (n = 40) or sham stimulation (n = 37) of the tremor-dominant hand. Tremor was measured before and immediately after a single 40-minute session of stimulation, and patients were asked to perform tasks in accordance with the Essential Tremor Rating Assessment Scale or TETRAS, a severity measure.

Subjects in the intervention group had about a 65% improvement in their upper-limb TETRAS scores, compared with those receiving sham treatment (P less than .01) and in total TETRAS performance (P less than .05).

Subjects also were tested in-clinic with props simulating common daily tasks such as unlocking a door with a key, holding a cup of tea, picking up loose change, or dialing a phone. Patients in the treatment group self-reported greater ease with all of these tasks after treatment, compared with the sham-treated group. Differences for some tasks reached statistical significance.

 

For the second study, conducted for 4 weeks, 61 patients were randomized to at-home treatment sessions with the neuromodulator or sham treatment for 40 minutes at least twice daily. Those receiving treatment (n = 31) saw greater reduction in tremor measured by the devices’ built-in sensors, compared with those assigned sham treatment (n = 15) or no treatment (n = 15). Nearly all sessions completed resulted in a measurable reduction of tremor.

In an interview at AAN, Manish Gupta of Cala Health, the device manufacturer, said that further studies are underway to assess the durability of the treatment.

“What we seem to be looking at is an on-demand therapy that delivers a transient relief,” Mr. Gupta said, adding that the devices could be used by patients at times when their tremor is most bothersome, or in anticipation of a task – such as dressing oneself or eating – that a tremor would affect the ability to perform.

“One thing we’re learning from clinicians is that tremor is variable within the patient, and it’s variable across patients,” Mr. Gupta said. “The same patient may find that they have less tremor a certain day or at certain times of the day. We don’t think this would replace deep-brain stimulation, which is a constant treatment effect, but it could serve for some patients as a step before it.”

Cala Health, the manufacturer, sponsored the study. One coauthor is an employee of Cala Health.

SOURCE: Pahwa R et al. AAN 2018, Abstract P4.474.