Sleep Apnoea Linked to Memory Loss
Research has shown that people with sleep apnoea, or problems which hinder their breathing during sleep, may be more likely to experience memory problems as they age.
US scientists analysed the medical histories of 2,470 people between the ages of 55 and 90, and divided them into three groups: those with Alzheimer’s disease, those with mild cognitive impairment (MCI), and those without any memory or thinking problems. They looked at whether the subjects had any breathing problems during sleep, and whether the affected were receiving treatment for these problems.
The results showed that those with sleep-breathing problems were diagnosed with MCI at an average age of 77, compared to an average age of 90 for those without such problems. Those who experienced breathing problems during sleep were also more likely to be diagnosed with Alzheimer’s at an average age of 83, while those who were free from sleep-breathing problems were more likely to develop the disease at an average age of 88.
In those with sleep apnoea, the muscles around the throat relax and block the airways during sleep, making it difficult to breathe. The researchers have speculated that this could mean that vital organs, including the brain, are not getting the oxygen they require, and that this could cause an increased risk of memory and thinking problems. However, further research is needed to clarify the link.
“This adds to growing evidence that disrupted breathing during sleep could be a risk factor for memory and thinking decline in older age, but it doesn’t prove one causes the other,” says Dr Simon Ridley, of Alzheimer’s Research UK. “A good supply of oxygen to the brain is vital to keep it healthy, and it is interesting to see that treatment of sleep apnoea was associated with a trend towards later memory and thinking problems.”
“Several earlier studies have shown that the quantity and quality of sleep we get can have an impact on our cognitive health,” says Dr Doug Brown, of the Alzheimer’s Society. “As sleeping disorders are common among the elderly, it is vital that we see more research into this area.”