Increasing Drowsiness & Dementia Risk
- Women in their 80s who experience notable changes in their sleep patterns may face an elevated risk of developing dementia, according to a recent study published in the...
- The research, which followed a group of older women over five years, suggests that increased sleepiness could be an indicator of cognitive decline.
- Participants wore wrist devices to monitor their sleep and circadian rhythms for three consecutive days at the beginning of the study and again five years later.
Study Links Sleep Changes in Older Women to Dementia Risk
Table of Contents
- Study Links Sleep Changes in Older Women to Dementia Risk
- Study Links Sleep Changes in Older Women to Dementia Risk: Your Questions Answered
- What’s the main takeaway from the study linking sleep changes to dementia risk?
- Who was included in this study?
- How long did the study last?
- How was sleep monitored?
- What specific sleep changes were observed?
- What were the diffrent sleep pattern groups identified in the study?
- did any women develop dementia during the study?
- How did sleep pattern changes relate to dementia risk?
- Does the study prove that sleep changes cause dementia?
- Can circadian rhythms change quickly?
- What are the limitations of this study?
- What does this study mean for older women?
- What are the next steps in understanding the relationship between sleep and dementia?
- Summary of Key Study Findings
Published May 5, 2025
Women in their 80s who experience notable changes in their sleep patterns may face an elevated risk of developing dementia, according to a recent study published in the journal Neurology.
The research, which followed a group of older women over five years, suggests that increased sleepiness could be an indicator of cognitive decline. Researchers analyzed data from 733 women, with an average age of 82.5 years at the study’s outset, who were free from cognitive impairment between 2002 and 2009.
Participants wore wrist devices to monitor their sleep and circadian rhythms for three consecutive days at the beginning of the study and again five years later. They also maintained sleep logs and underwent neuropsychological testing throughout the follow-up period.
Over the five-year span, the participants’ average total sleep time increased by 18.7 minutes, and their sleep efficiency, a measure of sleep quality, improved by an average of 0.94 percent. The duration of daytime naps also increased by an average of 33.1 minutes.
Fluctuating Sleep Patterns Linked to Higher Dementia Risk
the study identified that approximately 44 percent of the women maintained stable sleep patterns. Another 34.9 percent exhibited decreasing nighttime sleep, reduced sleep quality, and slightly longer naps. The remaining 21.3 percent experienced a significant increase in both the duration and quality of sleep during the day and night,according to the researchers.
During the study, 93 women, or 12.7 percent, developed dementia. the risk of developing dementia was two to three times higher for women in the groups with decreasing nighttime sleep or greatly increased sleeping time and quality compared to those with stable sleep patterns.
After adjusting for demographic factors such as age, education, ethnicity, and certain health conditions, the researchers found that the group with increased sleepiness had twice the risk of dementia compared to women with stable sleep. The association between decreasing nighttime sleep and dementia was less pronounced after the data adjustment.
While the study does not establish a direct causal link between increased sleepiness and dementia, the researchers suggest that changes in sleep patterns over time may indicate a heightened risk of dementia in women.
Circadian Rhythms Can Shift Rapidly in Older Women
“We observed that sleep, napping, and circadian rhythms in women in their eighties can change dramatically within just five years,” said Yue Leng, professor of psychiatry at the University of California, San Francisco, and senior author of the study, in a press release.
Leng emphasized the need for further research to examine all aspects of daily sleep patterns to better understand how changes in these patterns relate to the risk of dementia over time.
The researchers noted that over 90 percent of the study participants were white women, highlighting the need for additional research to determine if the same associations exist in non-white women. Sleep researchers, not involved in the study, suggested in an accompanying editorial that the findings should serve as a “wake-up call,” urging recognition of the effects of sleep disorders on dementia.
Study Links Sleep Changes in Older Women to Dementia Risk: Your Questions Answered
What’s the main takeaway from the study linking sleep changes to dementia risk?
the primary finding is that women in their 80s who experience significant changes in their sleep patterns may face an elevated risk of developing dementia.This research, published in the journal Neurology, suggests that increased sleepiness could be an indicator of cognitive decline.
Who was included in this study?
This study focused on a group of 733 women. At the begining of the study, these women had an average age of 82.5 years and were free from any cognitive impairment.
How long did the study last?
the study followed the participants for five years.
How was sleep monitored?
Participants wore wrist devices to monitor their sleep and circadian rhythms. This was done for three consecutive days at the beginning of the study and again five years later. They also kept sleep logs and underwent neuropsychological testing throughout the study.
What specific sleep changes were observed?
Over the five-year period, the study revealed several changes:
Increased Sleep Time: the average total sleep time increased by 18.7 minutes.
Improved Sleep Quality: Sleep efficiency (a measure of sleep quality) improved by an average of 0.94 percent.
Longer Naps: The duration of daytime naps increased by an average of 33.1 minutes.
What were the diffrent sleep pattern groups identified in the study?
The study identified three primary groups based on sleep patterns:
Stable Sleep Patterns: Approximately 44% of the women maintained consistent sleep patterns.
Decreasing Nighttime Sleep: 34.9% of the women experienced decreased nighttime sleep, reduced sleep quality, and slightly longer naps.
Increased Sleep Duration and Quality: 21.3% of the women showed a significant increase in both the duration and quality of sleep during the day and night.
did any women develop dementia during the study?
Yes, during the five-year study period, 93 women (12.7%) developed dementia.
How did sleep pattern changes relate to dementia risk?
The risk of developing dementia varied substantially depending on the sleep pattern group:
Decreasing Nighttime Sleep & Increased Sleep Time and Quality: Women in these groups had a two to three times higher risk of developing dementia compared to those with stable sleep patterns.
Increased Sleepiness: After adjusting for demographic factors,women with increased sleepiness had twice the risk of dementia compared to those with stable sleep.
Does the study prove that sleep changes cause dementia?
No, the study does not establish a direct causal link. Though,the researchers suggested that changes in sleep patterns over time may indicate a heightened risk of dementia in women.
Can circadian rhythms change quickly?
Yes, the study’s senior author, Yue Leng, noted that sleep, napping, and circadian rhythms can change dramatically within just five years in women in their eighties.
What are the limitations of this study?
One major limitation is the study population. Over 90% of the participants were white women. The research highlights the need for further studies to determine if the same associations exist in non-white women.
What does this study mean for older women?
The findings offer a “wake-up call” (as described by sleep researchers in an accompanying editorial) about the potential impact of sleep disorders on dementia risk. While further research is necessary, the study suggests that monitoring sleep patterns could be a useful tool.
What are the next steps in understanding the relationship between sleep and dementia?
Researchers emphasize the need for further study to examine the extensive aspects of daily sleep patterns.This will involve investigating how any changes in these patterns relate to dementia risk over time. Additionally, research is needed to assess if the same patterns remain in other demographics.
Summary of Key Study Findings
here’s a summary of the key findings from this study:
| Finding | Result |
| ————————————————- | ————————————————————————————————————————————— |
| Prevalence of Dementia in the Study | 12.7% of participants developed dementia over five years. |
| Dementia Risk (Decreasing Nighttime sleep) | 2 to 3 times higher risk compared to stable sleep patterns. |
| Dementia Risk (Increased Sleepiness) | Twice the risk compared to stable sleep patterns,after adjusting for demographic factors. |
| Change in Total Sleep Time | Average increase of 18.7 minutes over five years. |
| Change in Daytime Naps | Average increase of 33.1 minutes for the duration of daytime naps. |
| Population Demographics | Primarily white women (over 90%), highlighting the need for additional research to determine if the same associations exist in non-white women. |