Severe hypoxia Sleep apnea increases the risk of dementia

Lack of oxygen can cause regions in the brain to shrink?

So-called sleep apnea is a common condition that negatively affects breathing during sleep. Researchers have now found that sleep apnea-induced hypoxia causes shrinking of certain regions of the brain that are also affected by dementia.

The researchers from the University of Sydney found in their recent research that sleep apnea might favor the development of dementia. The physicians published the results of their study in the English-language journal "European Respiratory Journal".

With a special breathing mask, the nocturnal breathing interruptions of obstructive sleep apnea can usually be avoided. (Image: BVDC / fotolia.com)

Association between sleep apnea and shrunken brain regions

Sleep apnea is a common condition in which a person has frequent respiratory pauses or flat breathing during sleep. Experts have now observed in their research that sleep apnea depletion is associated with the shrinking of brain regions, which also play an important role in remembering and learning new information. Obstructive sleep apnea (OSA) subjects had reduced thickness in their temporal lobes. In addition, they performed worse in memory tests.

Should sleep clinics carry out memory tests?

Screening could identify obstructive sleep apnea, which could help to prevent deterioration of memory by offering patients special treatment to support the airways during sleep, physicians explain. The findings indicate that obstructive sleep apnea should be sought especially in older people, says study author Prof. Sharon Naismith of the University of Sydney. Elderly patients should talk to experts in sleep clinics about problems with their memory and their thinking skills. If necessary, tests should also be carried out.

83 subjects were examined for the study

Sleep apnea often occurs at an older age. Obese people are often affected as well. Sleep apnea increases the likelihood of developing high blood pressure, diabetes and sleep disorders. All these factors are also linked to dementia, say the experts. For their study, the researchers examined a total of 83 people aged 51 to 88 years, in which their doctor had previously observed memory problems, which may be an early sign of dementia. None of these participants previously had a diagnosis of obstructive sleep apnea.

Smaller temporal lobes caused worse storage of information

Memory tests and MRI scans were performed on each subject to assess their brain thickness. In addition, the subjects visited a sleep clinic, where their blood oxygen levels were measured overnight. It turned out that people with a lower blood oxygen level had shrunken right and left temporal lobes. These people were less able to store new information.

The lack of oxygen triggers inflammation in the brain?

The researchers also found increased thickness in other regions of the brain, which may be indicative of inflammation and swelling caused by oxygen deficiency. The research team is now investigating whether people in this at-risk group can benefit from treatment with a ventilator and mask.

Lifestyle factors greatly affect the risk of dementia

There is no cure for dementia, early intervention is key, says Professor Naismith. Treatment with a ventilator and mask is an effective treatment for obstructive sleep apnea, and diagnosing and treating obstructive sleep apnea may be a way to prevent cognitive decline before it is too late. Up to 50 percent of a person's dementia risk is thought to be caused by preventable lifestyle factors such as smoking, obesity, and high blood pressure. The influence of sleep disorders is being further investigated. (As)