Man in his forties (40s) snoring in bed with type 2 diabetes and OSA.

Blindness is a big risk for those with type 2 diabetes and OSA.

Of the 29 million adults with diabetes, 90 to 95 percent of all diagnosed cases have type 2 diabetes, according to the CDC. Another large percentage of adults with this disease also have obstructive sleep apnea (OSA), which may or may not be the cause of type 2 diabetes. OSA is a condition that makes it hard to sleep, causing snoring and interrupted breathing during the night. These symptoms occur when you have a blockage in your throat during sleep, due to a large neck or small airways. Overall, OSA makes it difficult to breathe at night.

Researchers continue to look for the link between type 2 diabetes and OSA through several studies. The most recent study looking into the connection between the two reveals a startling discovery. Left untreated, people with both type 2 diabetes and OSA are at greater risk. These patients can develop a condition that causes blindness.

Diabetic Retinopathy

Around 40 to 50 percent of patients with diabetes have diabetic retinopathy, the most common form of diabetic eye disease. In fact, this condition is the leading cause of blindness in the western world. High blood sugar levels can cause damage to the blood vessels in your retina. When this occurs, the blood vessels will either:

  • Swell and leak
  • Close, stopping blood flow
  • Or grow abnormal blood vessels

You can find out more from the American Academy of Ophthalmology by clicking here.

How the Condition Develops With Type 2 Diabetes and Sleep Apnea

The study at the University of Birmingham is the first to look at the impact of OSA on diabetic retinopathy. It also leads towards the theory that OSA can cause or worsen your diabetes. The researchers tested 230 patients with Type 2 diabetes, accessing them for both OSA and diabetic retinopathy.

“Firstly, we showed that sight-threatening diabetic retinopathy was more common in patients with both Type 2 diabetes and OSA compared to those with Type 2 diabetes but without OSA,” states Doctor Abd Tahrani. Dr. Tahrani is the corresponding author of the University of Birmingham’s Institute of Metabolism and System Research.

“However, more importantly, we have shown that patients with OSA and Type 2 diabetes, compared to those with diabetes only, are at increased risk of developing advanced diabetic retinopathy over a period of three years and seven months.”

Researchers found that the prevalence of diabetic retinopathy was 42.9 percent in those with OSA. This is higher than the prevalence in those with just type 2 diabetes. Meanwhile, after reviewing the patients 43 months later, the researchers discovered that those with OSA were 18.4 percent more likely to develop a moderate to severe case of the disease.

“Our findings are important because improved understanding of the pathogenesis of diabetic retinopathy is important in order to identify new treatments,” states Dr. Tahrani.

“Following our research, it is important that clinicians treating patients with Type 2 diabetes are aware that their patients who also have OSA are particularly at increased risk of developing advance retinopathy and, hence, appropriate preventative measures should be put in place.