Dementia Risk Linked to Sleep; New Study Suggests Early Bedtime or Sleeping Too Long Increases the Chances of Developing the Disease

New research recently suggested that the time an individual goes to sleep may increase his chances of experiencing cognitive decline and developing dementia.

A research team from Sweden, China, and the United Kingdom discovered a 69-percent higher dementia risk in people who sleep for longer than eight hours and a twice higher risk for those going to bed before 9pm versus 10pm or later, a UPI report specified.

In addition, the findings suggest that there is a need for cognitive function to be monitored in older adults reporting prolonged sleep and early bedtime, specifically in senior males whose ages range from 60 to 74 years old.

According to the study's lead author, Dr. Rui Liu, in the Department of Neurology at Shandong University's Shandong Provincial Hospital in Jinan, China, future studies "may help clarify" if moderately decreasing time in bed and delaying the timing of sleep can slow down cognitive decline and delay the onset of dementia on older adults.

Link Between Sleep and Dementia

The study, published in the Journal of the American Geriatrics Society, included approximately 2,000 older adults in China who were dementia-free at the start of the research.

Ninety-seven of these participants were diagnosed to have dementia during an average follow-up period of 3.7 years.

The authors of the study emphasized that most research on sleep and dementia has been carried out among nearly exclusively White populations in Europe and North America and has failed to focus on rural elderly.

Based on the study, this is essential because older adults who live in rural areas of China, as compared to Western populations and city dwellers, typically go to bed earlier, get up earlier, get poorer and inadequate sleep, not to mention, are more vulnerable to dementia, partly attributable to differences in culture, socioeconomic status, lifestyle, and education.

Sleep Duration

Dementia risk as linked to sleep does not only mean longer hours of sleeping but shorter duration too. According to a Mail Online report, in past research patients who get both "under six and more than nine hours of sleep have suffered from worse health outcomes through short sleep tend trends to be more dangerous.

Researchers measured beta-amyloid levels, a protein in the brain that's usually found at high levels when a patient is developing Alzheimer's disease.

Additionally, the research team used several memory or brain tests, attention, executive function, and spatial skills to identify the cognitive abilities of the patients

Factors Affecting Sleep and Cognitive Decline

To attempt to fill in the knowledge gap, the research targeted rural-dwelling the elderly, mostly low-income and with limited education, in western Shandong Province.

The researchers noted that problems with sleep, as well as cognitive decline, are known to be associated with demographics including gender, education, and age.

Furthermore, the study investigators also said that a well-established genetic risk factor for dementia has been linked to short sleep duration.

Yet, at present, population-based studies have generated mixed outcomes about associations between sleep problems and dementia, the research specified.

The team also acknowledged the limitations of their own study and said that the results need to be interpreted with caution since sleep traits were self-reported, there was a lack of data factors like sleep apnea, and the period of follow-up monitoring was comparatively short.

Related information about sleeping too much and dementia risk is shown on Boston University School of Medicine's YouTube video below:

Check out more news and information on Dementia and Technology in Science Times.