Adrenaline:
When one wakes from sleep, the adrenal gland secretes adrenaline (also known as epinephrine) into the bloodstream. If this stress hormone remains high, hypertension can result.
Additionally, when breathing is obstructed during sleep, there is a drop in oxygen levels. This hypoxia coupled with the high adrenaline in the bloodstream can cause irregular heart rate and dangerous arrhythmias.
Insulin:
OSA disrupts healthy glucose function and decreases insulin sensitivity. Insulin is the hormone responsible for regulating blood sugar levels, and when the body becomes resistant to it, blood sugar levels remain high.
Several studies have shown that sleep apnea correlates with prolonged hypersecretion of insulin, creating insulin resistance in the patients. This is a precursor to diabetes, and should not remain untreated.
Additionally, insulin is responsible for stimulating sodium retention by the kidneys, contributing to water retention and hypertension.
Cortisol:
In sleep apneic patients, cortisol levels are higher than that of non-sleep apneic controls. This is due to the fact that nocturnal awakenings are associated with elevated cortisol release. Cortisol is responsible for controlling blood sugar levels (cortisol provides the body with glucose by stimulating the liver to perform gluconeogenesis on stored proteins), regulating metabolism, and reducing inflammation. However, as stressful condition persist, and cortisol levels remain high in the blood, the blood sugar levels of the patient remains elevated.
High cortisol combined with insulin resistance can lead to diabetes if left untreated. Use of a CPAP significantly lowers both blood pressure and cortisol levels, which in turn lowers blood glucose levels to a normal state.
References:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2128620/
https://www.sleepapnea.com/blog/post/93116542331/osa-and-insulin-resistance-a-link-its-common
http://www.peakakron.com/syndrome-x-insulin-resistance-and-hyperinsulinemia.html
http://www.naturalmedicinejournal.com/journal/2010-06/role-cortisol-sleep
By: Jennifer LaBombard