Next to cancer, Alzheimer’s Disease (AD) and dementia is probably the most worrying health problem facing the western world today.
A large number of clinical trials have failed to show any benefit of the tested drugs in stabilizing or reversing the steady decline in cognitive function that is suffered by dementia patients.
Although the pathological features of Alzheimer's Disease (AD) consisting of beta-amyloid plaques and tau tangles are well established, considerable debate exists concerning the genetic or lifestyle factors that predispose individuals to developing dementia.
Photobiomodulation (PBM) describes the therapeutic use of red or near-infrared light to stimulate healing, relieve pain and inflammation, and prevent tissue from dying. In recent years, photobiomodulation (PBM) has been applied for a diverse range of brain disorders, frequently applied in a non-invasive manner by shining light on the head (transcranial photobiomodulation (tPBM)).
The present review discusses the mechanisms of action of transcranial photobiomodulation (tPBM) in the brain, and summarizes studies that have used tPBM to treat animal models of Alzheimer's Disease (AD).
The results of a limited number of clinical trials that have used transcranial photobiomodulation (tPBM) to treat patients with Alzheimer's Disease (AD) and dementia are discussed.
The fact that transcranial photobiomodulation (tPBM) may produce a large range of beneficial changes in the brain, and is without any major side-effects, suggests it should be more widely tested for Alzheimer's Disease (AD) and dementia in large controlled trials. Exposing the head to light at power levels less than that received in direct sunlight (but without harmful ultraviolet wavelengths) is intrinsically safe. Any side-effects reported have been rare, mild and transient, consisting of slight headache, difficult sleeping and mild itching on the scalp. It is likely that transcranial photobiomodulation (tPBM) for Alzheimer's Disease (AD) will need to be continued indefinitely, as regressions have been observed when photobiomodulation (PBM) treatments have ceased.
Home use transcranial photobiomodulation (tPBM) devices can be applied by the caregivers, who consistently report improvements in their own quality of life.