Monash study ties midlife OSA to memory loss and dementia risk factors
Monash University researchers linked sleep apnoea to poorer memory and a higher burden of dementia risk factors in 2,795 cognitively healthy adults aged 40 to 70.
The study appeared in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association and used data from the Australian Healthy Brain Project.
All 2,795 participants completed online assessments of thinking skills and health before researchers compared people with and without Obstructive Sleep Apnoea, or 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.
People with OSA often have loud snoring, gasping or choking during sleep. In the Monash study, participants with OSA performed worse on memory tasks than participants without the condition.
That difference was mainly seen in untreated OSA. Meanwhile, participants receiving treatment performed similarly to adults without OSA.
Obesity, blood pressure and cholesterol
Researchers also found a greater number of dementia risk factors in participants with OSA, including obesity, high blood pressure and high cholesterol.
Those vascular and lifestyle risks explained part of the link between OSA and poorer memory. However, they did not fully explain the lower memory scores seen in the OSA group.
First author Gabriel Abdelmessih is a Monash University PhD candidate in Clinical Neuropsychology in the School of Psychological Sciences.
Abdelmessih said: “Sleep apnoea is common, frequently undiagnosed, and highly treatable, yet it is not often considered in discussions about dementia risk.”
According to Monash University, the findings support earlier identification and management of sleep apnoea in midlife, before significant cognitive decline appears.
Abdelmessih said: “Our findings suggest that identifying and managing sleep apnoea in midlife may represent an important opportunity to support long-term brain health.”
He also said sleep apnoea often appears alongside other modifiable dementia risk factors, including obesity, high blood pressure and high cholesterol.
Because the Australian Healthy Brain Project group was cognitively healthy, the results suggest memory differences and dementia risk may emerge before old age or diagnosis.
Following the comparison of treated and untreated OSA, only untreated participants showed clearly poorer memory, while treated participants looked similar to adults without OSA.
