Could Sleep Apnea Be Raising Your Dementia Risk? What Researchers Found About the Connection

Roughly 29 million Americans have sleep apnea, and many have no idea the condition may be quietly reshaping their brain while they sleep. Here is what researchers now say about the link to dementia and what you can do about it.

What is sleep apnea and why does it matter for your health?

Sleep apnea is a condition in which breathing stops or becomes very shallow during sleep because the airway is partially blocked, with each pause lasting at least 10 seconds. The brain then signals the body to wake and resume breathing, a cycle that can repeat five to more than 100 times an hour.

“When a normal person falls asleep who doesn’t have sleep apnea, the airway stays open. But in someone who has sleep apnea, the airway does not stay open and an individual stops breathing,” Dr. Aatif Husain, professor of neurology and chief of the Division of Epilepsy, Sleep and Clinical Neurophysiology at Duke University Medical Center, told GQ. An estimated 29 million Americans live with the condition. Nearly one in five women have it, though nine out of 10 remain undiagnosed.

How does untreated sleep apnea affect the brain?

Repeated pauses in breathing drop oxygen levels in the brain, setting off a stress response that raises blood pressure and heart rate and, over time, damages blood vessels and brain tissue.

“Repeated apnea episodes cause drops in oxygen levels in the brain. This triggers a panic response, raising blood pressure and heart rate. Over time, this accumulated stress damages blood vessels and the brain itself,” said Dr. Alberto Ramos, professor in the Sleep Medicine Division at the University of Miami Miller School of Medicine. His most recent study, involving more than 3,000 participants, found that sleep apnea can reduce the size of important brain areas including the hippocampus.

“The hippocampus is key for consolidating memory. We also observed changes in small blood vessels, which increase the risk of dementia and Alzheimer’s over time,” Ramos said.

Can treating sleep apnea lower your dementia risk?

Growing evidence suggests it can, and the window for prevention appears to open in midlife. A meta-analysis of nine observational studies found that obstructive sleep apnea may more than double the risk of cognitive decline or Alzheimer’s disease.

Researchers point to several overlapping mechanisms. Breathing interruptions reduce blood oxygen and damage brain cells. Sleep apnea is also linked to hypertension, cardiovascular disease and depression, each of which independently raises Alzheimer’s risk. Fragmented sleep further impairs memory consolidation. Cognitively healthy older adults with the condition may already show altered Alzheimer’s biomarkers, and those markers can worsen over time.

“The ideal time to identify and treat these breathing problems is between 40 and 50 years old, when it’s still possible to prevent brain changes linked to years of poor-quality sleep,” Ramos said.

How do you get diagnosed with sleep apnea?

Most patients start with a referral from a primary care doctor to a sleep specialist, who reviews symptoms and orders a sleep study. That study can happen in a lab or at home through a Home Sleep Apnea Test (HSAT), which patients pick up, use overnight and return.

Warning signs include loud snoring, daytime sleepiness, obesity, older age and being male, though you can snore heavily without having sleep apnea and have sleep apnea without much snoring, according to Johns Hopkins. A newer at-home option, the Happy Ring by Happy Health, bundles an FDA-cleared sleep test, a board-certified sleep doctor consultation and personalized care that can be handled from home.

“What makes this so profound is that untreated sleep apnea has so many links to chronic medical conditions that we see, such as heart disease, heart failure, stroke, hypertension, diabetes, obesity,” Dr. Heidi Doss Riney, chief medical officer at Nox Health and medical director at Fusion Sleep Center in Georgia, told Nox Medical.

What are the treatment options, and is a sleep apnea pill on the way?

The current standard is a CPAP (Continuous Positive Airway Pressure) machine, which uses a mask to push air through the nose and mouth to keep the airway open overnight. An oral appliance that pulls the jaw forward to keep the tongue from blocking the airway is another option.

A once-nightly pill is also in development. A Phase 3 clinical trial published in May 2026 in the American Journal of Respiratory and Critical Care Medicine tested AD109, a combination of aroxybutynin, a novel antimuscarinic, and atomoxetine, a selective norepinephrine reuptake inhibitor. Researchers reported marked improvement in airway obstruction and oxygenation compared with placebo. The drug could have “utility across all levels of disease severity and a wide range of weight classes,” the authors wrote, adding that “AD109 may fill a large unmet need in providing patients with a pharmacologic therapy targeting the neuromuscular dysfunction underlying OSA pathogenesis.” Developer Apnimed is seeking FDA approval and hopes for a green light next year.