Digital medicine is far from a new concept. In 1745, the Leyden phial, a jar used to store electric charge, passed an “electrical fire” through the body and jump-started a revolution of using electricity in medicine. More recent milestones include the discovery of X-rays in 1895, the invention of the modern defibrillator in 1930, and the portable defibrillator which was invented in Belfast in 1965. The steady march of progress is apparent in medicine, and the ever-increasing lifespan of the world’s population is credited to this. But, today, are electric pharmaceuticals, devices that treat ailments with electrical impulses, practical for long-term use?
The history of electric pharmaceuticals, known as electroceuticals, shows how once technology becomes available, people seek to apply it in healthcare. The first electric hearing aid in 1898 used the technology which was made available by the invention of the telephone and the microphone to help those with impaired hearing. The science behind the implanted pacemaker developed so quickly that the first person to have it fitted in 1958 ended up outliving his doctor.
Medicine has moved to the forefront of technological advances as the twentieth century progressed. Deep-brain stimulation is a procedure that involves implanting a neurostimulator in the patient that sends electrical impulses to the brain. Deep-brain stimulation as a treatment for Parkinson’s Disease dates back to 1987 and its success has led to its application across a spectrum of other conditions.
“The science behind the implanted pacemaker developed so quickly that the first person to have it fitted in 1958 ended up outliving his doctor.”
Vagus nerve stimulation (VNS) has been at the centre of huge developments in recent years due to the broad functions of the vagus nerve and the brain regions it can reach. VNS is a procedure that involves implanting a device to stimulate the vagus nerve with electrical impulses.
The vagus nerve is the longest nerve in the autonomic nerve system, and it is largely responsible for the primitive “fight-or-flight” response in humans. Many of the emotional responses in people stem from the vagus or somewhere along its loop. It acts as a feedback mechanism from our gut to our brain and it is also strongly linked to the heart and lungs. Time-tested stress-busting techniques such as meditation, breathing techniques and yoga have a direct effect on the vagus nerve which explains, in part, their effectiveness.
The VNS implant is currently just under 4 cm in diameter, but the goal for the future is to make it smaller and more finely programmable. Devices are usually placed beneath the skin under the clavicle and they deliver impulses at prescribed regular intervals. Some devices can be controlled by an external “wand” which delivers the impulse to the vagus when the wand is held near the implant.
There has been a focus on treating autoimmune and inflammatory disorders with VNS since the late twentieth century. In studies, sufferers of ailments from Crohn’s disease to rheumatoid arthritis generally noted a reduction in the severity of their conditions thanks to VNS. Not only were physical symptoms reported to have subsided, but psychological research shows stress relief and alleviation of depression in subjects following a VNS implant. When the activity of the vagus nerve is strengthened, one’s ability to deal with stress becomes greater. In clinical tests, 86% of patients noted some improvement in their stress tolerance after just ten minutes of VNS a day over six weeks.
The advantages of VNS over traditional drugs and over-the-counter medications are numerous. Since only the vagus is targeted, as opposed to the whole body, the risk of side effects is dramatically lowered. The success of the treatment in clinical trials has lead to much more investment and research into VNS as a medicinal solution. Pharmaceutical company GlaxoSmithKline recently invested $715 million with research organisation Verily into developing bioelectronic medicines. The Defense Advanced Research Projects Agency (a subsidiary of the US Department of Defense) is investing in it for military personnel.
“Psychological research shows stress relief and alleviation of depression in subjects following a vagus nerve stimulation implant.”
Based on the results being returned by electroceuticals and VNS, the future is bright. Non-invasive treatments are also being examined, such as the ActiPatch, which minimises pain in targeted areas of the body. Electrical bandages like this prove to be much more effective than ordinary sticking plasters, as wounds heal faster when a small current is added.
There are also drawbacks owing to the novelty of this treatment method. Cost is a significant challenge faced by VNS, as it does not have the benefits brought by mass production that established medicines experience. Directly related to this is the tailor-made nature of the technology at present. The devices are surgically placed below the clavicle and an ideal amplitude and frequency are found for individual patients. While small, the peripheral nerves surrounding the vagus nerve still have some chance of being impacted by its stimulation.
In terms of practicality, electroceuticals are a mixed bag. The results are promising, and the technology is feasible, as illustrated by the VNS tests that have been carried out. On the other hand, it is a costly venture that relies on growing investment to continue. It is estimated that chronic conditions affecting two billion people in the next 20 years are treatable with VNS, which would make the widespread production of the technology much more viable. The industry is relatively new and, having accomplished so much already, the future looks promising.