The Link Between Obstructive Sleep Apnoea and Cardiovascular Diseases

Cardiovascular disease is one of the top killers in the world today. This group of diseases affect the heart and the blood vessels. These diseases include coronary heart disease, cerebrovascularr disease, peripheral artery disease, rheumatic heart disease, congenital heart disease, deep venous thrombosis and pulmonary embolism. Coronary heart disease affect the blood vessels that are located in the heart muscles while cerebrovascular disease involves the blood vessels that supply the brain. Peripheral artery disease involves the arteries that supply the limbs while rheumatic heart disease is caused by damage to the heart muscles and heart valves due to streptococcal bacteria. Congenital heart disease is caused by malformations of the heart structure which may exist at birth. Deep vein thrombosis and pulmonary embolism are caused by blood clots in the leg veins which have the tendency to dislodge and be transported to the heart and lungs.

Not all people are prone to develop cardiovascular disease; only those persons who have risk factors can do so. These risk factors include unhealthy eating, sedentary lifestyle, smoking, alcohol abuse and lifestyle. Recently, more studies are focusing on the fact that obstructive sleep apnoea can also cause cardiovascular diseases.

Obstructive sleep apnoea is becoming more of a common condition. This condition is characterized by the abnormal collapse of the pharyngeal airways during sleep, further causing arousals and falls in oxygen saturation. When not treated, it can lead to cardiovascular events such as heart failure, arrhythmias, coronary artery disease, and pulmonary hypertension. A recent article published in Pulmonary Medicine talks about potential mechanisms linking OSA to CVD, acute cardiovascular effects of OSA, impact of OSA on natural history of CVD, cardiovascular effects of continuous positive airway pressure (CPAP) treatment, and therapeutic cardiovascular efficacy of emerging treatment for OSA and central sleep apnoea (CSA).

According to the authors, several mechanisms behind the link between obstructive sleep apnoea and cardiovascular disease are processes such as enhanced sympathetic activity, oxidative stress, systemic inflammation, and endothelial dysfunction. These processes promote atherogenesis which increases the likelihood of cardiovascular events. Also, sleep apnoea is associated with decreases in blood oxygen concentration which further causes long term hypoxia and enhance atherosclerosis development. Hypoxia generates inflammation and proinflammatory cytokines such as tumour necrosis factor-α and interleukin-8, substances which have been implicated in the development of cardiovascular diseases.

In many studies, researchers have proven the link between obstructive sleep apnoea and cardiovascular diseases, atherosclerosis, hypertension and endothelial dysfunction. There were also evidences that different treatment strategies for sleep apnoea such as as oxygen therapy, CPAP, bilevel positive airway pressure (BIPAP), and adaptive servoventilation (ASV) have positive effects on obstructive sleep apnoea patients with cardiovascular diseases.

This is why experts recommend that sleep apnoea should be treated as soon as possible. Sleep apnoea has the possibility of leading to cardiovascular diseases in the long run. Also, patients with cardiovascular diseases should get tested for sleep apnoea to improve their quality of life and life expectancy.

Reference:

Alvarez-Sala R, García-Río F, Del Campo F, Zamarrón C, Netzer NC. Sleep apnoea and cardiovascular diseases. Pulm Med. 2014;2014:690273.

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