Sleep Apnea and Blood Sugar Swings: What New Research Shows

Obstructive sleep apnea—a condition where breathing repeatedly stops and starts during sleep—affects many people with diabetes. Researchers have long suspected a connection between sleep problems and difficulty managing blood sugar, but until now, no one had thoroughly reviewed all the evidence.

Glycemic variability, or the up-and-down swings in blood glucose levels throughout the day and night, is an important part of diabetes management. Large swings can increase health risks, even when average blood sugar levels look reasonable on paper.

A systematic review published in 2026 examined 14 studies on this topic. Researchers looked at nine studies testing CPAP therapy—a machine that keeps airways open during sleep—and five observational studies.

When researchers pooled results from single-arm studies (where everyone received CPAP), they found that treatment was linked to meaningful reductions in nighttime blood sugar variability. Specifically, nocturnal standard deviation decreased, and the amplitude of blood sugar swings at night showed some improvement.

However, when researchers looked at overall 24-hour blood sugar control across all studies, the improvements were less clear. Results varied depending on which measurement the researchers used to assess blood sugar variability.

The review included 14 studies, but only one focused specifically on people with Type 1 diabetes. This is a significant limitation. Most of the evidence comes from people with Type 2 diabetes, so it's unclear whether these findings apply equally to those managing Type 1.

More research is needed to understand whether treating sleep apnea can help improve blood sugar control in the Type 1 diabetes community.

If you have diabetes and suspect you may have sleep apnea—signs include loud snoring, gasping during sleep, and daytime sleepiness—it's worth discussing with your doctor. Untreated sleep apnea can complicate diabetes management and affect overall health.

If you're diagnosed with sleep apnea and offered CPAP therapy, the current evidence suggests it may help smooth out blood sugar swings, particularly at night. However, CPAP is primarily a treatment for sleep apnea itself, which has its own health benefits. Any changes to your blood sugar management should be discussed with your diabetes care team.

Source: Journal of sleep research. Evidence type: PubMed indexed literature. Type1Cure is an information and intelligence hub, not a medical advice service. This article summarizes published research and does not provide diagnosis, treatment, or personal medical guidance. Always talk to your own care team before changing anything about your Type 1 diabetes management.