Medical Complications

Hypertension

Apnea and hypopnea episodes during sleep cause acute blood pressure changes. Nightly episodes of hypoxia, arousals and swings in chest pressure and effort due to obstructive sleep apnea (OSA) may lead to sustained elevation of blood pressure.

OSA is an important risk factor for hypertension. An association appears to be present even at the mild end of the OSA spectrum. The high prevalence of OSA implies that it may be responsible for a substantial portion of the population burden of hypertension. [1]

Stroke

Sleep-disordered breathing has been linked to stroke in previous studies… These data demonstrate a strong association between moderate to severe sleep-disordered breathing and prevalent stroke, independent of contributing factors. They also provide the first prospective evidence that sleep disordered breathing precedes stroke and may contribute to the development of stroke. [2]

Diabetes

Diabetes is more prevalent in Sleep-Disordered Breathing (SDB) and this relationship is independent of other risk factors. However, it is not clear that SDB is causal in the development of diabetes. [3]

Daytime Sleepiness

Excessive daytime sleepiness is a cardinal feature of the OSA syndrome… there is evidence that both OSA and non-apneic snoring are important causes of daytime sleepiness…. [In one study] approximately 23% of women and 16% of men with an AHI of 5 or more reported experiencing three measures of sleepiness (excessive daytime sleepiness plus awakening unrefreshed no matter how long they had slept plus uncontrollable daytime sleepiness that interfered with daily living) 2 days or more per week…

[In another study] there was a significant increase in Epworth Sleepiness Scale (ESS) score with increasing AHI. AHI is the total of apneic events (cessation of breathing of 10 sec or more) and hypopnea events (drop of oxygen saturation by more than 4%) divided by hours of sleep.

A number of epidemiological studies have evaluated the relationship between snoring and daytime sleepiness and almost all have found an insignificant association. As snoring is a strong marker of the presence of OSA, the association of snoring with sleepiness might be due to their joint association with OSA; however, several studies suggest that snoring is independently associated with excessive sleepiness…

… studies suggest that snoring without frank apnea and hypopnea episodes is associated with daytime sleepiness independent of AHI. If so, the very high prevalence of snoring in the adult population suggests that public health burden of snoring-related sleepiness might well exceed that of overt OSA. [4]