An independent Australian group has done a study on the implication of obstructive sleep apnoea on systemic hypertension in young to middle-aged people. The study also aimed to link the reduction of high blood pressure in some patients when OSA is addressed or treated. Also concluded is the fact that severe OSA is highly linked to increased stroke, cardiovascular diseases and mortality in middle-aged people.

Cardiovascular diseases and type 2 diabetes mellitus is prevalent in OSA patients this is so because sporadic hypoxia coupled with irregular sleep notably leads to proinflammatory state which could lead to cardiovascular disease (CVD) and insulin resistance (IR). Studies indicate that obstructive sleep apnoea is a risk factor for CVD and IR, and not relating to obesity.

Diabetes and Insulin Resistance

Studies point out that OSA is a contributing factor in aggravating type 2diabetes and IR. In this connection, diabetes may worsen OSA through neuropathy and weight gain due to insulin use. Recent statistics showed that prevalence of type 2 diabetes in OSA patients stands from 23% to 86%.

Systemic Hypertension

About 30% to 86% of people with systemic hypertension have OSA. Patients with untreated OSA are more likely to develop hypertension as indicated by T-cross sectional studies. Furthermore, middle-aged patients with untreated OSA are three times more likely to develop systemic hypertension in four to eight years. This study, however, is not applicable to people aged 65 and above as additional risk factors are evident in this age bracket to form a conclusion.

Cardiac Arrhythmias

Episodes of benign cardiac arrhythmias, including atrial fibrillation, bradycardia (slow heartbeat), tachycardia (fast hearbeat), irregular heartbeat and heartblock, are commonly associated with OSA. Researches indicate that patients with severe OSA of more than AHI>31/h are more at risk to ventricular tachycardia, atrial fibrillation and quadrigeminy in which the heartbeats come in 4s.

Stroke

Studies conclude that patients, including those aged 65 and above, with undiagnosed and untreated OSA have a greater risk of having stroke. Some of the symptoms of stroke include atrial fibrillation during sleep involving blood clot formation and pulmonary hypertension, swings in systemic blood pressure and possible damage to the carotid artery. The increase risk for ischemic stroke in a person is linked to the severity of his OSA. Men with an AHI >19/h is three times more likely to develop stroke whereas the risk for women is significantly lower.

Heart Failure

OSA patients have an increased risk of diastolic and systolic heart failure. Studies conclude that patients with severe OSA (more than AHI>30/h) are three times more prone to diastolic and systolic heart failure as compared to those without OSA. On the other hand, the same study indicates that central sleep apnoea and OSA are common in people with heart conditions.

People with severe and untreated OSA (AHI>30/h) have an increase mortality compared to those with controlled OSA, mild to moderate OSA, and those with no OSA or other sleep disorder. The fact is, people with untreated, severe OSA have a higher mortality risk.

But this should not be a cause of alarm because with the right CPAP treatment therapy,

OSA Is manageable and treatable.