Key points
New research has found sleep apnoea is linked to poorer memory and a greater burden of dementia risk.
Routine screening for sleep apnoea may support long-term brain health.
Improving the management of sleep apnoea, along with its associated vascular risk factors such as obesity and high blood pressure, may support healthy cognitive ageing.
Better identification and management of sleep apnoea and associated vascular risk factors in midlife may provide an important opportunity to support long-term brain health, according to new research from Monash University.
The study, published in Alzheimer's & Dementia: The Journal of the Alzheimer's Association, investigated the link between sleep apnoea, thinking skills and dementia risk factors in cognitively healthy middle-aged adults.
The 2,795 participants, aged 40-70 years and enrolled in the Australian Healthy Brain Project, completed online assessments of thinking skills and health. The researchers compared cognitive performance and dementia risk factors between individuals with and without Obstructive Sleep Apnoea (OSA).
OSA is a common sleep disorder in which the airway repeatedly narrows or collapses during sleep, causing breathing to stop or become shallow for short periods. The condition is often accompanied by loud snoring, gasping or choking during sleep.
The study found participants with OSA had poorer memory than those without the condition. Specifically, poorer memory was primarily observed among individuals with untreated OSA, while those receiving treatment performed similarly to participants without the condition.
Researchers also found that participants with OSA had a greater amount of dementia risk factors, including obesity, high blood pressure and high cholesterol.
While these vascular and lifestyle dementia risk factors explained some of the link between OSA and poor memory, they did not fully explain why people with OSA performed worse on memory tasks in this study.
First author Gabriel Abdelmessih, Monash University PhD candidate in Clinical Neuropsychology from the School of Psychological Sciences, said the findings emphasise the importance of identifying and managing sleep apnoea early in life, well before any significant cognitive decline becomes apparent.
"Sleep apnoea is common, frequently undiagnosed, and highly treatable, yet it is not often considered in discussions about dementia risk," Mr Abdelmessih said.
"Our findings suggest that identifying and managing sleep apnoea in midlife may represent an important opportunity to support long-term brain health.
"Importantly, sleep apnoea often co-occurs with other modifiable dementia risk factors, including obesity, high blood pressure and high cholesterol.
"Our findings highlight the importance of considering sleep apnoea alongside these other health factors when assessing an individual's risk of future cognitive decline and dementia."
Researchers now want to investigate whether treating sleep apnoea and other related vascular risk factors together could help protect brain health and lower the risk of dementia as people age.
Read the research paper: https://doi.org/10.1002/alz.71553
