In this article, Air Liquide Healthcare explained how the cardiac risks is associated with sleep apnea, how it contributes to the risk of sudden death, why testing is so crucial, and the importance of sleep apnea therapy in reducing this risk.
Why is sleep apnea so dangerous?
Sleep apnea is a problem in which you repeatedly stop breathing while you sleep. Sleep apnea affects over 2.5 million Australians, while many more have it unknowingly.
A large portion of the population, including some primary care physicians, is uninformed of the dangers of untreated obstructive sleep apnea. This may be a contributing factor to the widespread underdiagnosis of sleep apnea.
The health concerns of sleep apnea are far more significant than the fact that you won’t get enough good sleep even if you get the recommended 7-9 hours every night. Some examples are insulin resistance, hypertension, and impotence (an early warning sign of vascular issues). As with diabetes, obstructive sleep apnea (OSA) is linked to an increased risk of cardiovascular disease (CVD) death.
Many cardiovascular diseases, including atrial fibrillation, heart failure, and first-degree block, are linked to obstructive sleep apnea.
Lack of oxygen is a symptom of obstructive sleep apnea. When we sleep, our oxygen intake drops, which can lead to oxidative stress, or an imbalance between free radicals and antioxidants.
Endothelial dysfunction, in which the heart’s blood vessels narrow and constrict rather than dilate and open, and atherosclerosis (a buildup of plaque on the artery walls) are two conditions that may be more common in people with untreated or undiagnosed sleep apnea because of the resulting imbalance.
In addition, the efficacy of therapies for other health issues may be diminished if sleep apnea is left untreated. There are implications for the management of conditions such as diabetes and hypertension.
This is because sleep-related increases in blood pressure and insulin are a direct result of airway blockages. As a result of treating the underlying causes of the apneas and hypopneas (partial airway blockages), the nighttime surges can be reduced or eliminated.
Please see our supplementary material for further information on the fatal consequences of sleep apnea and the annual number of deaths attributable to cardiovascular causes.
Sleep Apnea and the Risk of Sudden Cardiac Death
The occurrence of sudden cardiac death (SCD) is tragically prevalent yet preventable. Cardiovascular disease is the largest cause of death worldwide, and SCD is its most prevalent symptom.
There has been scant research into the causal relationship between OSA and cardiac arrest. However, more and more studies are looking at sleep apnea as a risk factor, and they’re finding several links.
A sleep study is needed to infer any incidence link, which may explain why there is so little research exploring the connection between OSA and SCD. Not until recently has there been any study that adequately followed up with a sizable population and recorded all the relevant data.
Obstructive Sleep Apnea and Low Oxygen Saturation
Due to airflow obstruction, sleep apnea lowers blood oxygen levels. According to the aforementioned study, not only does this generate significant oxidative stress in the body, which negatively impacts heart health, but it is also a predictor of unexpected mortality.
In particular, the lowest oxygen saturation value that a patient had at night was associated with an increased risk of sudden cardiac death. An additional 14% risk was seen for every 10% drop in oxygen saturation.
Another study found that between midnight and 6 a.m., individuals with OSA had a 2.57-fold higher relative risk of nocturnal (nighttime) sudden cardiac death compared to the general population. The risk of sudden death in those with severe obstructive sleep apnea is directly related to the number of hypopnea episodes (how often breathing is interrupted).
Over-arousal of the central nervous system is thought to develop in those with sleep apnea because of the lower oxygen saturation that happens during the night.
The power and speed with which your heart contracts are both the result of activation of the sympathetic nervous system, which also produces vasoconstriction of blood vessels. During sleep, the sympathetic nervous system is activated, increasing heart rate and contractile force to enhance cardiac output and provide oxygenated blood to the body.
This sympathetic activity at night is a major contributor to cardiovascular morbidity and death in people with OSA. In other words, cardiovascular disease and the resultant mortality are strongly linked to the activation of the sympathetic nervous system during sleep.
Recent studies highlight a relationship between OSA and SCD, and fresh evidence emphasises the need of treating sleep apnea.
Checking your risk factors and being tested if you believe you have sleep apnea is crucial since the connection between OSA and sudden cardiac death is complicated. You should get tested for sleep apnea if you snore, experience breathing interruptions while sleeping, are overweight, or have a family history of the disorder.
Treatment for Sleep Apnea: Why It’s So Crucial
If you or a loved one suffer obstructive sleep apnea, this new information may cause concern. However, the risk may be significantly lowered with proper treatment.
There are studies looking at the effects of CPAP treatment on long-term cardiovascular outcomes, but none of them focus on sudden cardiac death. Six out of seven studies included in a meta-analysis showing the benefits of CPAP for cardiovascular health indicated that using the device considerably reduced the risk of cardiovascular events.
Treatment for sleep apnea using continuous positive airway pressure (CPAP) involves wearing a mask that applies gentle, steady pressure to the user’s airway while they sleep.
If you suffer from OSA symptoms, CPAP therapy is a safe, easily available, and effective therapeutic option—but only if you use your CPAP machine regularly and reliably.
In addition to CPAP therapy, making adjustments to your lifestyle can help reduce the impact of sleep apnea and heart disease on your quality of life. For the sake of your heart and your sleep, you should think about making the following adjustments if you haven’t already:
You should cut back on booze and cigarettes, work in 30 minutes of moderate exercise every day, and get rid of any extra weight that’s making breathing difficult.
Eat a healthy, balanced diet and get enough of sleep (here are a few recommended lifestyle changes for better sleep)
Consult a specialist at Air Liquide Healthcare as soon as possible if you suspect you have sleep apnea or another sleep condition. Take our sleep apnea questionnaire to find out whether you have this respiratory problem or are at risk for it.