Obstructive sleep apnoea (OSA) affects two per cent of all middle-aged women, and four per cent of all men, according to a 2002 study. OSA causes people to stop breathing while they are asleep. Young people are also vulnerable to this sleep disorder. It can lead to hypoxia – a condition in which a part of the body is deprived of oxygen – which can in turn have an impact on brain function. This is likely the reason why so many OSA patients feel that some of their functions have been impaired.
Not many studies have been done with regard to how OSA affects our hearing. Sounds enter the ear and are converted into brain signals. These signals are processed by the brain, which is why we understand what it is that we’re hearing. The brain helps us understand language and appreciate music. Without a properly functioning brain, we may be able to hear sounds, but we might have difficulty interpreting what they mean. That is why, for example, an injury to the head can significantly affect our ability to interpret sound.
Until recently, OSA was thought to have little impact on our ability to detect sound. Injuries in or around the ear were the main things that affected our hearing. We recently examined the impact the brain has on how we interpret sound by studying the brain of a rat which was suffering from OSA. This revealed that the functions of more than one region of the brain was affected by OSA. Portions of the brainstem responded less to sound, while the cortex responded more. Other regions of the brain that have a part to play in our hearing were relatively unaffected.
This study, combined with recent studies reporting auditory-processing deficiencies in OSA patients, is early evidence that OSA can affect our hearing, because it can affect the way our brain works.
This suggests there is a link between sleep disorders and hearing difficulties – two things which affect children, and may have an impact on their lives as they grow up. That’s why it’s important for young people and their parents to immediately talk to a doctor or a medical professional if they suspect there are problems that might harm their quality of life.