Sleep Disorders Offer a Potential Target for Alzheimer’s Disease Prevention

The relationship between Alzheimer’s disease risk and age-related sleep changes—and how barriers to sleep health possibly drive Alzheimer’s disease–related disparities—is the focus of ongoing research led by Omonigho M. Bubu, MD, PhD, MPH, an associate professor of psychiatry at NYU Langone Health and member of the Brain Aging and Sleep Center.

Dr. Bubu’s investigations offer a window into potential opportunities to target sleep disorders such as obstructive sleep apnea (OSA) before the onset of Alzheimer’s disease, potentially narrowing the disproportionate risk of Alzheimer’s disease in minority populations.

“We now know that around 15 percent of Alzheimer’s disease cases can be attributed to specific sleep problems,” says Dr. Bubu. “Clinically, that tells us that if we can eliminate sleep problems before major cognitive decline, we may be able to significantly reduce the Alzheimer’s disease risk burden—particularly among Black patients, who are twice as likely to experience sleep problems.”

Sleep Apnea as a Risk Factor

A retrospective analysis led by Dr. Bubu found a dose–response relationship in incident Alzheimer’s disease risk as OSA increased, driven specifically by underlying factors involved in OSA: hypoxia, sleep fragmentation, and sleep duration. He notes, though, that the precise causal relationship between OSA and Alzheimer’s disease onset remains under investigation.

While the study indicated that patients with OSA were significantly more likely to develop Alzheimer’s disease compared to those without OSA, the risk was notably more pronounced in Black and Hispanic patients.

Specifically, White patients with OSA were 1.7 times more likely to develop Alzheimer’s disease compared to their counterparts without OSA. In contrast, Black individuals with OSA were 2.2 times more likely and Hispanic patients with OSA were 1.8 times more likely to develop Alzheimer’s disease compared to their counterparts without OSA.

Early intervention could potentially head off the development of the progressive disease. Suggesting opportunities for such intervention, additional research from Dr. Bubu and colleagues has demonstrated a greater presence of Alzheimer’s disease biomarkers in cognitively healthy older patients with OSA, including amyloid burden and tau protein aggregation. Concurrent vascular risk factors, including hypertension, were found to further promote amyloid burden and global cognitive decline.

Research into Disparities and Interventions

Now, with over $8.5 million in funding from the National Institute on Aging, Dr. Bubu is applying a health disparities research framework to further investigate the effects of race on the relationship between OSA and Alzheimer’s disease pathology.

The five-year study will involve 300 race-, age-, and sex-matched participants—half with newly diagnosed OSA. Data on social determinants of health from the study could support prospective investigations of novel prevention strategies for Alzheimer’s disease that target stress management, inflammation, hypertension, and sleep quality.

“By prioritizing sleep in patient education and promoting adherence to effective treatments for sleep problems, physicians may be able to help their patients effectively slow the onset and progression of cognitive decline.”

Dr. Bubu’s ongoing research has also found that plasma strongly mirrors brain scans in revealing the presence of certain Alzheimer’s disease biomarkers. These biomarkers, including tau, point to a future role for blood-based screening, which could provide a simple tool to assess Alzheimer’s disease risk.

In the meantime, his findings to date suggest an immediate clinical benefit to prioritizing sleep in the evaluation and management of patients—particularly Black patients.

“The effects of social determinants on sleep—and the connection between sleep problems and neurodegeneration—are a critical piece of the whole health outcomes puzzle,” said Dr. Bubu. “By prioritizing sleep in patient education and promoting adherence to effective treatments for sleep problems, physicians may be able to help their patients effectively slow the onset and progression of cognitive decline.”