2022 Alzheimer's Association Research Grant to Promote Diversity (AARG-D)

OSA Treatment Impact on Brain Injury Biomarkers and Functional Connectivity

How can treating obstructive sleep apnea impact biological markers associated with Alzheimer’s?

Korey Kam, Ph.D.
Icahn School of Medicine at Mount Sinai
New York City, NY - United States

Background

More than 50% of individuals with dementia experience sleep disruptions or poor sleep patterns that precede cognitive impairment by several years. Studies also suggest that sleep deprivation may increase Alzheimer’s risk by promoting the accumulation of abnormal beta-amyloid and tau proteins which form plaques and tangles respectively, both hallmark brain changes associated with Alzheimer’s.

Past studies suggest that sleep loss may impact brain function by reducing the ability of brain cells to communicate with each other or by damaging certain brain structures. The locus coeruleus is a brain region known to be important for regulating sleep. Studies show that the locus coeruleus is one the brain regions vulnerable to change in the early stages of Alzheimer’s.

Obstructive sleep apnea (OSA) is a sleep disorder that is increasingly prevalent as people age. Studies show chronically untreated OSA can lead to accumulation of beta-amyloid plaques as well as subsequent memory impairment. The most common treatment for OSA is continuous positive airway pressure (CPAP) therapy, in which a machine increases air pressure in the throat to help a person breathe more easily during sleep. However, little is known about how CPAP treatment impacts biological markers (biomarkers) and brain changes associated with Alzheimer’s.

Research Plan

Dr. Korey Kam and colleagues will study the impact of CPAP treatment on biomarkers of Alzheimer’s in the blood and brains of older individuals with OSA. The researchers believe that differences in CPAP treatment adherence may allow them to evaluate treatment effects on the concentrations of Alzheimer’s biomarkers in the blood and on the function and structure of the locus coeruleus.

The research team will recruit 50 older adults newly diagnosed with OSA. After the first visit, participants will undergo 15 days of at home sleep measurements prior to starting CPAP treatments. During a second visit, participants will have blood drawn for biomarker analysis and undergo a brain scan to study the structure and function of the locus coeruleus prior CPAP treatment. In a final visit, after CPAP treatment has begun, participants will provide blood again. They will also undergo another brain scan as well as record an additional night of at home sleep on the CPAP treatment.
 

Impact

This study may provide a better understanding of how obstructive sleep apnea impacts the brain and impacts Alzheimer’s risk. These results may also inform sleep-related interventions that may slow or prevent the onset or progression of Alzheimer’s.