The Revitalize Study in Older Adults at Risk for Alzheimer's Disease

Résumé succinct

The goal of this multi-site double blinded randomized sham-controlled Phase II clinical trial is to test a novel, relatively low cost, low risk, and potentially high impact therapeutic intervention in older adults who are at increased risk for Alzheimer's disease. The intervention involves transcranial and intranasal delivery of near infrared (NIR) light via light emitting diodes, aka photobiomodulation (PBM). The overall hypothesis, based on animal and pilot studies, is that exposure to NIR stimulation will have beneficial effects on brain health via influence on mitochondrial function as measured by changes in 31Phosphorous (31P) MRS-based markers of ATP, neural network changes in functional connectivity (rs-fMRI), and improved cognitive performance. To test this hypothesis, 168 older adults with subjective cognitive complaints, and a first-degree family history of Alzheimer's disease will be randomized to sham or real treatment groups. Neuroimaging and cognitive outcome measures will be obtained, before and after a 12-week intervention involving transcranial and intranasal NIR-PBM. The intervention protocol will involve "lab" and "home" sessions, and a 3 month post-intervention follow-up. This trial will determine: 1) whether NIR stimulation, relative to sham, improves performance on memory and executive tasks sensitive to hippocampal and frontal brain function in older adults with increased risk for Alzheimer's disease; 2) whether NIR stimulation, relative to sham, enhances brain function and connectivity measured by changes in MRS phosphorous ATP and resting state functional connectivity; and 3) how differences in demographic, neuroimaging, and Alzheimer-related risk factors influence the brain response to NIR stimulation versus sham in older adults with increased risk for Alzheimer's disease. Results will provide key insights into whether this novel NIR intervention can enhance cognition in older adults with increased risk for Alzheimer's disease and will provide the necessary data for a future Phase III randomized clinical trial.