Yes, that's right... untreated obstructive sleep apnea can contribute to the development of type 2 diabetes.
Wait... OSA can cause diabetes?
No. But if you look at the way sleep apnea affects the body, you can see how leaving it untreated can create conditions for type 2 diabetes to take root.
The brain and the body work together in a neurochemical fashion to operate all its system stress hormones.
If body chemistry becomes unbalanced over long periods of time, it can lead to the disruption of these same systems.
How untreated OSA sets the stage for diabetes
Sleep apnea provides the very kind of dysfunction that leads to systemic imbalance.
Think about it: a person with OSA experiences blocks to their air supply for at least ten seconds at a time, and often quite frequently. Over the course of the night, that can translate into hundreds of moments when the bloodstream is short on oxygen.
Any time you don't have enough oxygen in the bloodstream, you experience hypoxia. When hypoxia happens, the brain and body respond by flooding the bloodstream with stress hormones to initiate an arousal so that you can consciously breathe and correct the imbalance.
Every once in a while, this is not a problem. But when it happens dozens to hundreds of times a night, it alters chemistry in a way that can lead to a new "normal."
Insulin resistance: a new "normal"
One of the key problems with repeated hypoxic events during sleep is that they lead to this constant system correction. Over time, the outcome is elevated blood sugar levels and impaired insulin sensitivity.
Unchecked insulin sensitivity leads to insulin resistance, which leads to glucose intolerance and, eventually, type 2 diabetes.
This is not to say that you will automatically develop a case of type 2 diabetes if you have sleep apnea. But studies do confirm that its risk factors multiply for those who are not vigilant about treating their OSA.
The uninvited guest: How obesity factors into both sleep apnea and diabetes
A third factor that can influence the development of both sleep apnea and diabetes is weight gain.
People with untreated sleep apnea can become overweight due to these same chemistry imbalances. The sleep fragmentation caused by arousals from apnea leads to sleep deprivation, which we now know is a major risk factor for obesity.
Sleep deprivation tends to increase the amounts of ghrelin in our bloodstream. This is the hormone which increases appetite, and too much of it leads to snacking that's motivated by daytime fatigue.
Ghrelin's counterpart, leptin, is a metabolic regulator that typically signals when the body is full, but for people with OSA, leptin levels drop, leading to overeating and, eventually, obesity.
To compound matters, obesity results in excess tissue around the neck. This additional weight, while the body reclines, serves to mechanically worsen sleep apnea, with longer pauses in breathing and more difficulty waking up to breathe again. More systemic stress means the body has no other choice but to live inside this new chemical "normal," one which can eventually trigger type 2 diabetes.
The sleep problems of diabetics
Diabetics already suffer from poor sleep even without having an identifiable sleep disorder. High nocturnal glucose counts force the kidneys to excrete excess sugar, leading to multiple trips to the bathroom, for one thing. Diabetics may need to rise and eat a light snack to keep their blood chemistry balanced, as well. A night of disrupted sleep is often the norm for the diabetic.
These people also struggle to maintain a good melatonin supply. This is important, because melatonin not only regulates circadian rhythm function, it also supervises insulin release from the pancreas to balance out high blood sugar. Without enough melatonin to perform this task, metabolic imbalance ensues.
Diabetics also struggle with leptin resistance. This is problematic because leptin helps stabilize breathing patterns and lung function during sleep. Researchers think this may potentially explain a diabetic's predisposition to sleep apnea.
One more reason to treat your sleep breathing problems
We already have enough reasons for developing chronic diseases like diabetes. Studies show that treating sleep apnea can, by itself, offer relief for many other health conditions like hypertension, mood disorders, and diabetes.
If you snore loudly or have been told you gasp or pause while breathing while you sleep, please take it seriously. These are just some of the signs of sleep apnea. By treating it, you may be able to dodge other more devastating illnesses down the line.
American Academy of Sleep Medicine
National Sleep Foundation
Nature and Science of Sleep
PLOS - Medicine