Sleep apnoea and dementia

Sleep apnoea, is defined as a period of 2 missed breaths or greater. Only 2-4 percent of people in the UK are diagnosed with sleep apnoea. However, two recent studies suggest that ~90% of people are diagnosed and this number could be significantly higher - closer to half of men and a quarter of women over the age of 40. These are alarming statistics as sleep apnoea is linked to the biggest killers in the UK: Heart disease, respiratory distress, stroke, cancer, liver disease, and dementia. Patients with sleep apnoea, are 4 times more likely to die from a heart attack and stroke, are 5 times more likely to die from cancer, and have an increased occurrence of liver disease, diabetes, and metabolic syndrome. Furthermore, sleep apnoea leads to cognitive impairment and exacerbates neurodegenerative diseases, partially due to sleep deprivation, and we hypothesise partially due to the induction of neuroinflammation. Therefore, patients with sleep apnoea are likely to develop other long term and even fatal diseases. This is not only consequential to the patients and their loved ones, but it also has financial implications for the health service as it will contribute to the costs of these diseases to the NHS: £8.7 billion (cardiovascular disease), 9.6 billion (stroke), £5 billion (cancer), £3.5 billion (liver disease), £9.8 billion (diabetes), and 26.3 billion (dementia). Furthermore, certain medicines such as analgesia and anaesthesia are contraindicated for people with sleep apnoea, leading to complications both during and following surgery; a problem exacerbated by the fact these patients are often tired without knowing it and therefore they are involved in more major accidents, particularly car crashes. There are currently no appropriate experimental models of sleep apnoea, meaning that there is no good way of studying sleep disordered breathing except for monitoring patients breathing during sleep, which is both costly and time consuming. Therefore, we currently do not understand why people with sleep-disordered breathing develop these debilitating disorders. Without understanding the causes, we cannot prevent the outcomes. Ms Reno Roberts, who works in the Neurosciences division at the Warwick School of Life Sciences and this team have created a physiologically realistic and clinically relevant model of sleep apnoea, in which they will investigate the mechanisms that relate sleep apnoea to cognitive deficits and dementia, using cognitive behavioural tasks and electrophysiological recordings of neural tissue. The Medical and Life Sciences Research Fund is pleased to support this research and by identifying the relationship between sleep apnoea and these issues, in the future the aim is to develop new diagnostic tools to help identify at risk patients. This new model of sleep apnoea may also be used by pharmaceutical companies to test new therapeutics, or indeed therapeutics currently approved for use in humans. If the drugs already approved for use in humans prove effective in this model it could have an instant clinical impact, and if an experimental drug proves effective it could lead to clinical trials. Improved diagnostics and treatment regiments will stop the perpetual downward spiral in the health of these patients, and lead to improved patient outcomes and a better quality of life for patients, and their families and carers.