Sleep apnea can contribute to cardiovascular disease (CVD) and poor heart health in several ways.
Oxygenation
Sleep apnea causes repeated pauses in breathing during sleep, leading to corresponding drops in blood oxygen levels. This cycle of low oxygen followed by oxygen recovery can trigger systemic inflammation, oxidative stress (inability to detoxify the body), and activation of the sympathetic nervous system to speed up heart rate and breathing, which contribute to cardiovascular dysfunction and damage.
Response to danger
In addition to elevated heart rate, increased sympathetic nervous system activity (mechanisms that kick in to combat danger) increases blood pressure and cardiovascular workload during sleep. This can place additional strain on the heart and blood vessels over time, increasing the risk of chronic high blood pressure (hypertension), irregular heartbeats (arrhythmias), and many other cardiovascular complications.
Cycling oxygen levels and sympathetic nervous responses can impair the function of the lining of blood vessels (endothelium). This dysfunction is a precursor to atherosclerosis, the buildup of plaque in the arteries, which can lead to coronary artery disease, heart attacks, and strokes.
Metabolism
Sleep apnea is also associated with insulin resistance, glucose intolerance, abnormal lipid levels, and obesity. These are collectively known as metabolic syndrome. These metabolic disturbances are all independent risk factors for cardiovascular disease and can worsen the cardiovascular effects of sleep apnea.
Arrhythmias
Sleep apnea increases the risk of cardiac arrhythmias, including atrial fibrillation, ventricular tachycardia, and bradyarrhythmias (slow heartbeats). These abnormal heart rhythms can disrupt normal heart function, reduce cardiac output, and increase the risk of stroke and sudden cardiac death.
Mentation
Finally, sleep apnea can cause sleep deprivation, which has detrimental mental effects in addition to physical ones. Sleep deprivation can cause slower mental processes, confusion, errors in judgment, and worst - psychosis.
Overall, sleep apnea is closely linked to cardiovascular disease and poor heart health due to its effects on oxygenation, sympathetic nervous activity, endothelial function, metabolism, and heart rhythm. Treatment for sleep apnea can help mitigate these cardiovascular risks and improve overall heart health.
