Obstructive sleep apnoea (OSA) and other breathing conditions are common for many people who have COPD and other chronic lung conditions. People who suffer from OSA reduce or stop their breathing for short periods while sleeping because in deep sleep, the muscles of the throat relax and this may reduce the space at the back of the tongue, through which air must pass to reach the lungs. Normally this doesn’t cause any problems with breathing. In OSA, however, complete relaxation of the throat muscles may cause blockage of the upper airway so that breathing stops temporarily. Such an episode is called an apnoea. This can happen many times during the night. These breathing stoppages interrupt sleep which results in poor sleep quality with excessive sleepiness during the day. Because these events occur during sleep, a person suffering from OSA is usually unaware of them and is often the last one to know what is happening. In OSA, the breathing stoppages can last for ten or more seconds and the cycle of apnoeas and broken sleep is repeated hundreds of times per night in severe cases. Most sufferers are unaware of their disrupted sleep but awaken unrefreshed, feeling tired and needing more sleep.