Sleep Apnea and Diabetes Management

Approximately 6 million Americans have been diagnosed with sleep apnea, but that number only scratches the surface: The condition is thought to affect 39 million in total. 

Why should those of us with diabetes be concerned about that? Well, it turns out that sleep quality is deeply connected to how we manage diabetes and insulin. And, according to one study, up to 90 percent of people with type 2 diabetes have obstructive sleep apnea. The condition is also more prevalent in type 1 diabetes.

What Is Sleep Apnea?

Sleep apnea is a potentially serious health condition in which one’s breathing repeatedly stops and starts while sleeping. According to the Mayo Clinic, there are three main types of sleep apnea:

Obstructive sleep apnea (OSA): This is the most common form. Here throat muscles relax, which blocks the flow of air into the lungs.
Central sleep apnea (CSA): This is when the brain doesn’t send the right signals to the muscles that control breathing.
Treatment-emergent central sleep apnea: This is also known as complex sleep apnea. It emerges when someone with diagnosed OSA experiences a conversion to CSA while receiving OSA treatment.

Typically, the symptoms of sleep apnea include loud snoring, gasping for air while sleeping, waking up with a dry mouth, waking with a headache, insomnia, hypersomnia (excessive daytime sleepiness), difficulty focusing while awake, and irritability.

If you have any of these symptoms, it’s a good idea to see a doctor, who can arrange a sleep study to diagnose the condition and determine which type it is. Typically, the testing involves a referral to a sleep disorder center, where a sleep specialist can conduct tests using nocturnal polysomnography, equipment that monitors heart, lung, and brain activity, breathing patterns, arm and leg movements, and blood oxygen levels during sleep. Testing can sometimes be done at home using a simplified test that measures heart rate, blood oxygen level, airflow, and breathing patterns. But, noted the Mayo Clinic, it’s more likely that polysomnography in a sleep center will be recommended if CSA is considered likely. 

The causes may be genetic, but sleep apnea is most commonly found in people who are overweight or obese, who smoke, and who are older than 40. 

Why Is Quality Sleep So Important?

Sleep is not just a period of rest. Many physiological events take place while experiencing good-quality sleep. According to the National Heart, Lung, and Blood Institute, sleep:

Heals and repairs heart and blood vessels
Helps support a healthy balance of the hormones that make you feel hungry (ghrelin) or full (leptin). When you don’t get enough rest, levels of ghrelin go up and leptin go down, making you feel hungrier than if you have enough sleep.
Supports healthy growth and development in children and teens, including boosting muscle mass, and cell and tissue repair. It even has a role in puberty and fertility.
Affects the body’s ability to fight germs and sickness by promoting the body’s natural defenses against common infections
Decreases the risk of health problems, including heart disease, high blood pressure, obesity, and stroke

But one of the most significant impacts of sleep — and this is crucial for people with diabetes — is its influence on metabolic health: how it helps the body regulate blood sugar. 

Matthew Walker, a professor of neuroscience and psychology at the University of California, Berkeley, explained in a recent interview that deep sleep is critical for resetting the body’s ability to regulate insulin and therefore regulate glucose:

… deep sleep helps you better control your blood sugar response, and it helps the body and the cells of the body. Firstly, you receive more insulin signaling to say, hey, there’s more blood sugar around, it’s time for you to sort of take out the spike in glucose in your blood. And it helps the cells essentially stick the straws into the bloodstream and start sucking up the blood sugar, so you don’t get that dangerous spike.

Walker and other researchers at UC Berkeley released research in 2023 that points to a potential mechanism in humans that explains how and why deep-sleep brain waves can regulate the body’s sensitivity to insulin, which, in turn, improves blood sugar the next day.

These synchronized brain waves act like a finger that flicks the first domino to start an associated chain reaction from the brain, down to the heart, and then out to alter the body’s regulation of blood sugar … In particular, the combination of two brain waves, called sleep spindles and slow waves, predict an increase in the body’s sensitivity to the hormone called insulin, which consequentially and beneficially lowers blood glucose levels.

What that means is that sleep could in the future be used as part of a therapeutic treatment for people with type 2 diabetes and could map and predict someone’s blood sugar control. 

How Are Sleep Apnea and Diabetes Related?

If you have diabetes and sleep apnea, it can be more difficult to manage diabetes. According to the Cleveland Clinic, that pause in breathing can increase carbon dioxide in the blood, leading to insulin resistance that causes more sugar in the bloodstream and therefore high blood sugars. 

A 2016 study published by the American Diabetes Association (ADA) found that obstructive sleep apnea has been shown to increase the risk and severity of type 2 diabetes independent of age and obesity, which the researchers said was notable because age and obesity are risk factors for both OSA and type 2 diabetes.

But that’s not all: Sleep apnea can also cause chronic elevated blood pressure and a higher incidence of heart problems or cardiovascular disease.

There’s also behavioral fallout that comes from sleep apnea, which impacts people with type 2 diabetes among other diseases. If you haven’t had enough sleep you’re less motivated to exercise or plan healthy meals. It may lead to forgetting to take medications, which can contribute to other health complications.

Sleep Apnea Treatments

The most common treatment for sleep apnea is a continuous positive airway pressure machine, known commonly as a CPAP. It is geared for moderate to severe obstructive sleep apnea and delivers air pressure through a mask that’s worn during sleep. The air pressure it delivers keeps upper airway passages open to prevent apnea and snoring. Some people find it challenging to comfortably wear the mask, but there is more than one type of mask and ways to adjust it, so it’s worth experimenting with different styles.

For those who have difficulty adjusting to a conventional CPAP machine because it’s not providing air pressure correctly for them, there are also options. One is the auto-CPAP, which automatically adjusts air pressure during sleep. The other is a BPAP, which supplies bilevel positive airway pressure. In other words, it provides more pressure when you inhale and less while exhaling. 

A less effective, but easier to use option is an oral appliance designed to keep the throat open. 

According to the Mayo Clinic, surgery might be an option. The authority identifies six types of surgery that can help address sleep apnea: removing tissues from the rear of the mouth and top of the throat, along with tonsils and adenoids; shrinking tissues; repositioning the jaw; implanting soft rods to the roof of the mouth; and implantation of nerve stimulation device. In the most extreme, life-threatening cases, surgeons can use a tracheotomy to create a new air passageway. And, given the impact of obesity on both sleep apnea and diabetes, bariatric surgery is another option.

Then there are other nonmedical treatments beyond CPAPs identified by the Cleveland Clinic. These approaches aren’t cures but they could reduce sleep apnea to the point where it’s either not happening or isn’t severe enough to cause symptoms. These include:

Weight loss
Sleep position changes or sleep aid items like special support pillows to keep you off your back and prevent soft tissue from pressing on the windpipe
Nasal sprays and adhesive tapes that can help snoring and mild sleep apnea
Treating underlying conditions such as heart failure
Medication changes, including stopping or decreasing opioid pain medications

There are also some medications that may help with central sleep apnea, such as hypnotic medications and respiratory-stimulating drugs, although the Cleveland Clinic noted that they aren’t formally approved or definitely accepted for addressing sleep apnea.

Does Treating Sleep Apnea Improve Blood Sugar Management?

If obesity is contributing to sleep apnea, major weight reduction can reduce the severity of OSA and, according to Harvard Medical School’s Division of Sleep Medicine, could eliminate it. And, as we know, weight loss can help improve blood sugar management. Regular moderate to vigorous exercise can also improve OSA, along with blood sugar management. 

To be honest, it’s unclear if long-term treatment of sleep apnea with CPAP actually improves glycemia or prevents type 2 diabetes. A 2020 research paper published by the ADA reviewed the work of other researchers and concluded that CPAP, which it refers to as the gold standard treatment of OSA, “has not been consistently shown to improve glycemic control or reduce insulin resistance in clinical trials in which CPAP was used for 1-6 months.” 

One issue was CPAP adherence — study participants didn’t always use their devices. But in more controlled lab experiments researchers did find evidence that short-term CPAP did result in improved glucose metabolism. But, they noted, “Despite the evidence that OSA is linked to incident type 2 diabetes and dysglycemia [abnormal fluctuation of blood sugar levels], no long-term data exist as to whether CPAP treatment improves glucose metabolism in people with OSA and type 2 diabetes or whether it lowers conversion rate from prediabetes to type 2 diabetes.” 

Another literature review, conducted in 2023 by the University of California, San Diego Department of Medicine, also acknowledged mixed results on the impact of OSA treatment with CPAP, noting its possible relationship to poor CPAP adherence as well as “dietary indiscretion after symptomatic improvement with CPAP therapy”— or patient selection in the studies. 

Nevertheless, these researchers emphasized that “sleep health is often ignored despite its potential contributions to the treatment of OSA, obesity, and type 2 diabetes.” Stay tuned, in other words. Because, as these UCSD researchers noted, sleep apnea, and specifically OSA, is both underdiagnosed and undertreated in people with type 2 diabetes. More focused attention on integrating sleep health generally in treatment could help prevent obesity, OSA, and type 2 diabetes.

Conclusion

If you have type 2 diabetes, it’s quite possible that you also have sleep apnea. Because sleep apnea is so underdiagnosed — and because it can significantly impact your health — it’s worth discussing with your healthcare provider and getting tested. Treating sleep apnea, and getting proper sleep, could make it considerably easier to manage your diabetes.

Sources and Fact-Checking