The Health Risks Associated With Sleep Apnoea

There is no doubt that sleep apnoea can increase the incidence of death and cardiovascular disease. There are many studies that can prove this fact. It is said that untreated and severe sleep apnoea can give rise to increased risk for mortality and cardiovascular illnesses such as heart attacks and strokes. Recently, a study by Hudgel et. al published in the Journal of Clinical Sleep Medicine has evaluated the incidences of all-cause mortality, MI, CVA, and pulmonary embolus (PE) in people with obstructive sleep apnoea within a time span of 8 years.

In this study, adult patients greater than 18 years of age who underwent evaluation at the Henry Ford Sleep Disorders and Research Centre in 2001 and 2002 diagnosed with either primary snoring or obstructive sleep apnoea were studied. A total of 1,691 patients were recruited. The medical records of these patients including electronic medical records (EMR) and polysomnogram (PSG) records were obtained retrospectively. Patients were grouped whether they were non-apnoeic snorers (AHI of 0 to < 5), patients with mild OSA (AHI of 5-14), patients with moderate OSA (AHI of 15-29) and patients with severe OSA (AHI ≥ 30).

The study found out that those patients with severe obstructive sleep apnoea have the greatest number of adverse events. About 10% of those patients belonging to the age group ≥ 50 died; the rates were equal among males and females. About one-fourth of deaths and heart attacks and about one-third or more of strokes and pulmonary embolisms occurred in patients less than 50 years old. The adverse events were not related to BMI.

In those patients less than 50 years of age, all-cause mortality was predicted by the presence of severe obstructive sleep apnoea and by the presence of stroke, heart attacks and congestive heart failure. However in this subgroup of patients, the severity of obstructive sleep apnoea was not related to myocardial infarction, strokes and pulmonary embolisms.

In males, all-cause mortality was predicted by the presence of severe obstructive sleep apnoea and the history of congestive heart failure. This was consistent with previous studies which have observed that age, severe obstructive sleep apnoea, and arterial oxygen desaturation index are predictors of all-cause and cardiovascular mortality in males under the age of 70 years.

In females, all-cause mortality was predicted by histories of congestive heart failure and stroke. CPAP use of ≥ 4h/night was inversely proportional to mortality in patients with severe obstructive sleep apnoea.

Thus considering these facts, it is clear enough that younger male patients with severe obstructive sleep apnoea are highly susceptible to mortality and cardiovascular outcomes. Also patients with severe obstructive sleep apnoea who have previous cardiovascular illnesses are at risk of mortality and future cardiovascular illnesses. These patients should be prioritized in terms of sleep apnoea workups and treatments.

Reference:

Hudgel DW, Lamerato LE, Jacobsen GR, Drake CL. Assessment of multiple health risks in a single obstructive sleep apnoea population. J Clin Sleep Med. 2012 Feb 15;8 (1):9-18.

Image Courtesy of photostock / freedigitalphotos.net