Early dementia symptom Drowsiness a day may indicate future Alzheimer's disease

Daytime sleepiness may indicate later Alzheimer's disease

A recent study found that older adults, who are often drowsy during the day, are nearly three times more likely to have brain deposits of beta-amyloid. This protein is typical for years later on Alzheimer's disease .

In their recent research, scientists at the Johns Hopkins Bloomberg School of Public Health found that high levels of daytime sleepiness in older people indicate an increased risk of Alzheimer's disease. The physicians published the results of their study in the English-language journal "SLEEP".

If people often fall asleep during the day or are tired, this may indicate a later onset of Alzheimer's. (Image: Kaesler Media / fotolia.de)

Which factors influence the risk for Alzheimer's??

The long-term study shows that adequate nightly sleep may be a way to prevent Alzheimer's disease, say the experts. Factors such as diet, exercise and cognitive activity are widely regarded as important potential targets for the prevention of Alzheimer's disease, but sleep also appears to affect the onset of the disease, study author Dr. Adam P. Spira of the Johns Hopkins Bloomberg School of Public Health. When sleep disorders contribute to Alzheimer's disease, patients should be treated with sleep problems to avoid these negative consequences, the physician adds.

Where did the data used in the study come from??

The study used data from the Baltimore Longitudinal Study of Aging (BLSA), a long-term study initiated by the NIA in 1958 that medically monitored the health of thousands of volunteers in their old age. As part of the study's regular research, volunteers completed a questionnaire between 1991 and 2000, asking the simple question of whether participants often sleep or are tired during the day. In addition, it was questioned how often the subjects sleep during the day during the week, once or twice a week, three to five times a week, rarely or never.

Which investigations were carried out?

A subgroup of participants in the BLSA study also received a so-called neuroimaging study in 1994. Some of these subjects also underwent positron emission tomography (PET) from 2005 onwards. So plaques should be detected in the neuronal tissue. These plaques are a hallmark of Alzheimer's disease, explain the researchers.

How much was the risk for Alzheimer's increased?

Prior to adjusting the results to demographic factors that could influence daytime fatigue, such as age, gender, education, and body mass index, the study data showed that participants reporting daytime sleepiness were about three times more likely to have beta-amyloid deposition had as subjects who felt no fatigue a day. After adjusting for the factors mentioned, the increased risk of Alzheimer's in daytime sleepiness was still 2.75 times higher, the researchers report.

Sleep has a major impact on the risk of Alzheimer's

According to Spira, however, it is unclear why drowsiness during the day correlates with the deposition of beta-amyloid proteins. One possibility is that drowsiness on the day itself causes this protein to form in the brain, the experts explain. Based on previous research, a probable explanation is that sleep disorders such as obstructive sleep apnea or inadequate sleep due to other factors cause beta-amyloid plaques to form through a currently unknown mechanism, and these sleep disorders also cause excessive daytime fatigue. However, it can not be ruled out that amyloid plaques, which were present at the time of sleep evaluation, cause daytime sleepiness, the study author explains in a Johns Hopkins Bloomberg School of Public Health press release.

Television and shift work can worsen sleep quality

The new study shows that poor sleep could actually contribute to Alzheimer's development. The findings suggest that sleep quality may be a risk factor that can be affected by sleep disorders such as obstructive sleep apnea and insomnia, as well as social and individual factors such as sleep loss from work or television, according to study authors. (As)