Sleep apnea and diabetes are closely linked. Sleep apnea can significantly increase the risk of diabetes, and diabetes can enhance some of the serious risks related to sleep apnea. And both conditions can have a sweeping impact on your overall health as well as the health and function of individual systems.
One system that can be dramatically impacted by diabetes. Diabetic retinopathy can significantly damage your sight and can lead to blindness. Unfortunately, a new study shows that the risk of vision loss due to diabetes is greater if you have sleep apnea.
What Is Diabetic Retinopathy?
Diabetic retinopathy (DR) is a complication caused by changes in your blood and blood vessels related to diabetes. Diabetes is hard on blood vessels, especially small ones, such as the ones in your eye. When these blood vessels get damaged, your vision can suffer.
DR starts when diabetes causes damage to blood vessels in the eye, creating a shortage in the blood supply. When the body senses this shortage, it tries to grow new blood vessels. But these new blood vessels can distort and damage the retina. The new and old blood vessels can leak, causing a fluid buildup around the retina. The swelling, scarring, and other damage to the retina diminishes vision and may even cause it to be lost altogether.
Retinopathy More Common–and More Severe
DR is a common complication of diabetes, but it wasn’t known how much impact sleep apnea could have until recently. For this new study, researchers followed 230 patients with diabetes, none of whom had previously been diagnosed with sleep apnea. Nor had they been diagnosed with other respiratory conditions. At the start of the study, patients were tested for DR and sleep apnea. For DR, they used detailed scans of the eye. For sleep apnea, subjects were given a multichannel home test. These are both good diagnostic tests, which makes the study’s results more robust.
The test showed that 64% of the patients had sleep apnea and 36% had sleep-threatening DR (STDR). Although this coincidentally adds up to 100%, there was significant overlap between these two populations. In fact, researchers found that diabetics with sleep apnea were 2.3 times more likely to have STDR than those without sleep apnea.
The risks continued as researchers followed the population for an average of 43 months. They found that diabetics with sleep apnea were 5.3 times more likely to develop proliferative or pre-proliferative DR, a form that can turn into STDR.
Sleep Apnea Treatment Seems to Help
This study was mostly looking at risk, but it did come up with an incidental insight about the impact of treatment on the risk of DR. It seems that patients who got CPAP treatment during the study reduced their risk of developing proliferative DR. These results were statistically significant, but researchers warned that more studies should be done to confirm the result.
There are other studies that show sleep apnea treatment can help with diabetes. For some people, CPAP is a reasonable treatment, but for many people, oral appliance therapy is a better treatment because it is easier to comply with so people get better results.