TENS machine may offer new treatment option for patients with sleep apnea

A machine commonly used for pain relief has shown to improve breathing in patients with obstructive sleep apnea, a clinical trial has found.

Results of the TESLA trial, published today in eClinical Medicine by researchers from King's College London and Guy's & St Thomas' NHS Foundation Trust, shows the potential of a new therapeutic option for patients using a transcutaneous electrical stimulation (TENS) machine.

Sleep apnoea affects about 1 billion people worldwide, and millions in the UK. The condition can be frequently associated with snoring; people who are affected stop breathing many times during the night. The condition leaves people excessively sleepy during the day, lacking attention, and sometimes experiencing headaches. People diagnosed with sleep apnea are advised not to drive when feeling excessively sleepy.

Many people with sleep apnoea may use a continuous positive airway pressure (CPAP) machine, which pumps air into a mask you wear over your mouth or nose while you sleep. However, only about 75% of patients adhere to CPAP after 3-months, and after five years of treatment this is down to about 25%. Evidence-based alternatives for CPAP are limited but include a specialized mouth guard which pushes the lower jaw forward - known as a mandibular advancement devices (MAD) - and, in some cases, surgical options.

The TENS machine used in the TESLA trial is a small, battery-operated device that has leads connected to sticky pads called electrodes. It is commonly used to reduce pain from conditions such as arthritis and during labor, but has not been used for people with obstructive sleep apnoea before.

The TESLA trial shows this can be a cheap and non-invasive treatment method in responders. Patients with obstructive sleep apnoea were randomized and set to receive a TENS machine or CPAP. The light and continuous electric stimulation of the machine is enough to keep the airway open while asleep, allowing easy breathing to continue.

Patients treated with TENS showed improvements in nocturnal breathing and a significant reduction of daytime exhaustion.

The trial also shows that this treatment could be considered for patients who do not respond well to CPAP, providing a second line treatment that is cheaper and less time consuming to roll out than current alternatives.

Not all patients with obstructive sleep apnoea are able to use CPAP therapy, often because the mask can be uncomfortable and in severe cases can lead to sleep deprivation. Alternatives for CPAP include mandibular advancement devices, and sometimes surgical options like hypoglossal nerve stimulation (HNS) which requires a pre-assessment, surgical implantation, activation and follow up appointments.

In contrast, a TENS machine is non-invasive, has little side effects, and is cheap. The TESLA trial shows us the potential of a new therapeutic option, transcutaneous electrical stimulation, and it will be interesting to see how the method can be used in clinical practice."

Professor Joerg Steier, professor of respiratory and sleep medicine at King's College London and consultant from Guy's & St Thomas' NHS Foundation Trust

A multi-center trial is now being planned to prove efficacy in different healthcare systems.