Light therapy provides new hope for Alzheimer’s patients

Researchers have developed a new light technology that appears to improve cognitive function in Alzheimer’s patients in clinical trials. The hope is that the idea can be developed into ordinary lamps that people can install to prevent the disease.

Researchers at DTU and UC Berkeley, together with spin-out company OptoCeutics, have invented a non-medical form of therapy that can improve brain activity: light-based deep brain stimulation that induces a specific type of brain wave that Alzheimer’s patients benefit from. An article on the technology is published in the journal PLOS One.

Clinical trials conducted by doctors at Zealand University Hospital in Roskilde have shown a beneficial effect in preliminary studies on people with Alzheimer’s where these gamma brain waves were induced: The results suggest that patients with mild to moderate Alzheimer’s experienced improved cognitive abilities in relation to, e.g., speech and memory. A study involving more participants is underway to confirm the results.

DTU Professor Paul Michael Petersen, one of the inventors of the technology, says that the idea for the device is based on research from MIT. Nearly 10 years ago, their research showed that when mice with Alzheimer’s were exposed to blinking lights, gamma brain waves were induced, which in turn reduced plaque caused by beta-amyloid proteins in the brain.

The brains of Alzheimer’s patients are often characterized by the presence of plaque, which is harmful to nerve cells and can cause inflammatory changes in brain tissue.

“However, blinking lights are not particularly sound because they can cause discomfort and, in the worst case, epileptic seizures, so we wanted to investigate whether we could achieve the same effect but in a gentler way,” Petersen explains.

The professor, who is an expert in light, came up with the idea of developing a device that had the same effect as blinking lights, but where users would not detect that the light was blinking. The technology they developed achieves a beneficial effect on the brain while avoiding several negative side effects.

Good results

The device was first tested on healthy individuals to confirm that it could induce the desired brain waves, and then in trials where people with mild to moderate Alzheimer’s disease spent 30 minutes daily over a period of either six or 12 weeks in front of one of the new light devices or a placebo lamp. In the double-blind clinical trials, neither patients nor doctors knew what type of treatment the Alzheimer’s patients were getting.

At the conclusion of both the short and long trials, doctors were able to detect an improvement in cognitive function—i.e., the ability to perform tests that indicate brain problems—among patients who used the newly developed light technology. Scans also revealed that the brains of those who received the active treatment in the longer trial showed signs of improvement.

“In the patients who were given the placebo lamp, that part of the brain deteriorated, while we actually saw a small increase in volume in those who used an active lamp,” Petersen says.

Many factors can affect the cognitive abilities of Alzheimer’s patients. OptoCeutics is therefore now conducting a much larger study to document the effect of using the device on patients. Stronger clinical evidence could pave the way for the devices, which are already on the market, to be marketed and sold to more hospitals and clinics working with Alzheimer’s disease.

Great potential

The professor is eagerly awaiting the results of the ongoing trial.

“If we can stimulate patients’ brains so they avoid secondary diseases and see an improvement in their daily lives by reducing the consequences of losing their memory and not being able to orient themselves or speak, then that’s huge!” he says.

In the long term, Petersen envisions that the idea behind the device could be further developed and become an alternative to ordinary light sources that people can use as a preventive measure in their homes. “And perhaps it could be particularly relevant in retirement homes, where dementia is so prevalent.”

Inclusive innovation

The Danish-American partnership was established during DTU Professor Jes Broeng’s stay at UC Berkeley in 2017, where the innovation expert established a connection between brain researchers there and light experts at DTU.

“Jes Broeng contacted me, and we quickly developed the idea together and decided to submit a joint patent application and quickly verify whether the idea was viable,” Petersen says.

The first electrical circuit using new LED technology, from which the light device originated, was developed that same year during a three-week course by Marcus Carstensen, who was a master’s student at the time. He has since helped to further develop the light device—initially in his master’s project and then as a Ph.D. student at DTU Electro. Today, he is Chief Technology Officer at OptoCeutics.

“Marcus was an incredibly talented DTU student, and he quickly advanced the technology. In fact, this is a really good example of how DTU’s technical knowledge can be of benefit to society and why young engineers and students are so important and can make such a big difference,” Petersen says.

About Alzheimer’s

Dementia is the fourth leading cause of death in Denmark and Alzheimer’s disease is by far the most common form of dementia. Yet there are still only a few drugs available to treat Alzheimer’s, and they only have a temporary stabilizing effect on the disease.

The Danish Dementia Research Center estimates the number of elderly people in Denmark diagnosed with Alzheimer’s disease to be about 25,000. In most cases, the disease is not hereditary but occurs without any known cause.