Poor sleep may be faulted for dementia, the condition wherein symptoms of memory decline, reducing the ability of a person to perform daily activities. A recent study suggests men who are older and have less deep sleep time or difficulty in breathing are perhaps heading for brain changes that may be a precursor of dementia. While previous studies already suggest that poor sleep is one of the problems of dementia, the reason is still unclear.
Poor sleep has been found to perhaps contribute to dementia and cognitive impairment, according to Dr. Rebecca Gelber, the study leader of Honolulu-based VA Pacific Islands Health Care System. Specifically, they found, one-quarter of elderly men who were lacking sufficient oxygen that circulates in the blood during sleep, were four times likely to have more micro-infarcts in their brain compared to those whose oxygen levels are high.
Low oxygen levels can result from conditions such as sleep apnea or emphysema, wherein breathing goes on and off during sleep. Micro-infarcts are the small abnormality of the brain tissue, which can be signs that dementia may occur next. Also, men who experienced less restorative sleep stage or slow-wave sleep, the deep sleep, which helps process memories, showed their brain tissues have more atrophy.
Gelber explained that micro-infarcts, as well as atrophy, are more severe and common in people with dementia than in those without memory issues. Research says as people get older, they tend to have less slow-wave sleep time. Gelber also said that the study is the first one conducted to show sleep features that have something to do with changes in the brain.
Though not part of the study, Dr. James Leverenz, who is treating dementia at Cleveland Clinic supported the low level oxygen and micro-infarcts concept. He said, those who have lower oxygen levels in the blood when sleeping have more micro-infarcts, the small strokes correlated with problems with thinking skills and memory loss in aging.
While poor sleep may be faulted for dementia, medical experts are still not drawing conclusions. The research did not directly show poor sleep causing dementia and an expert suggested the need to be wary in the interpretation of the results. Director Keith Fargo of Chicago-based Scientific Programs and Outreach for Alzheimer’s Association said that the study results show an association between poor sleep and dementia, not cause-and-effect.
What Fargo likes to point is this study did not show sleep apnea itself to be related to the changes in the brain. People with poor sleep appear to likely have brain changes which are linked to dementia. There is the linkage, but the researchers still have to comprehend it. He emphasized it is important to research of sleep’s role in dementia first, as there are still numerous questions to be answered.
Meanwhile, Gelber said there are evidences that addressing sleep apnea can enhance mental performance, but it is not known yet if improving oxygen levels when sleeping reduces dementia risk. There is a need for more studies to check whether slow-wave sleep can restore the brain function and when there are ways to improve the time needed by an old person to spend in deep sleep.
Science Communications Manager Dr. Laura Phipps at Alzheimer’s Research UK, said a good sleep contributes to proper brain function, but more studies are needed to determine if sleep distractions could affect thinking skills when aging. She said a healthy diet, exercise and not smoking can reduce dementia risk.
Fargo noted that some people with sleep issues have problems with concentration, memory and thinking that are not associated with dementia at all. Poor sleep may be faulted for dementia, but it is not a definite fact yet. He advised people should see their physician if they have sleep distractions.
By Judith Aparri
Photo courtesy by Michael Galkovsky – Flicker License