Dementia is a syndrome linked to the ongoing decline of the brain – and there are a number of warning signs that can appear in the middle of the night, according to experts.News
Fiona Callingham Lifestyle writer
05:02, 01 Apr 2025
Certain problems with your sleep could be a warning sign of dementia(Image: Getty)
Experts have issued a warning that some of the early signs of dementia could manifest during sleep. Sleep-related symptoms could be an indication of cognitive decline before other more recognisable signs become apparent.
Dementia is a syndrome characterised by a group of symptoms related to ongoing brain deterioration. It’s most prevalent in individuals over 65, and symptoms such as memory loss can often be misinterpreted as normal ageing signs.
However, your sleep patterns could also be impacted. The Alzheimer’s Society has noted that individuals with dementia may experience specific sleep disturbances.
The charity explains on its website: “A person with dementia experiences physical changes in their brain because of their condition. These changes can affect how much, and how well they sleep.
“A person with dementia may struggle with sleeping at night, and may sleep more during the day. They may find it challenging to fall asleep or they may wake up frequently during the night. The individual you care for may not feel well-rested upon waking.
“Over time, if these issues persist, poor sleep may exacerbate the symptoms of dementia. This can be difficult to manage.”
The charity further elaborates: “For a person with dementia, achieving sufficient sleep can pose a challenge. Sleeping soundly can be problematic for individuals aged over 55, as the parts of the brain that regulate sleep may not function as effectively. An older person is likely to retire to bed earlier and may struggle to sleep through the night as they once did.”
According to the society, individuals with dementia might experience a range of sleep-related issues. They might:
- Sleep less deeply
- Sleep for less time overall
- Wake up several times during the night
- Have difficulty getting to sleep
Additionally, they may tend to sleep more during the day while struggling to sleep at night. “This process can start to happen even before a person has dementia, or if they have mild cognitive impairment (MCI),” the charity noted.
A recent study published in the journal Neurology suggests that one’s sleeping patterns might be able to predict the likelihood of developing dementia. The research indicates that people who feel increasingly sleepy during the day and perhaps take “excessive” naps could have double the risk of developing dementia.
Over a period of five years, the 733 study participants were categorised into three groups:
- Stable sleep (SS) – stable or slightly improved sleep, which 321 women (43.8 per cent) demonstrated
- Declining nighttime sleep (DNS) – decreases in nighttime sleep quality and duration, moderate increases in napping, and worsening circadian rest-activity rhythms (RARs), which 256 women (34.9 per cent) demonstrated
- Increasing sleepiness (IS) – large increases in both daytime and nighttime sleep duration and quality, as well as worsening circadian RARs, which 156 women (21.3 per cent) demonstrated
Researchers tracked the participants over five years to assess their cognitive state, categorising them as having normal cognition, mild cognitive impairment, or dementia based on multiple neuropsychological tests, physician diagnoses, or nursing home admissions.
Among the women in their 80s, the results showed that 164 (22.4 per cent) developed mild cognitive impairment, and 93 (12.7 per cent) developed dementia. Notably, the women whose sleepiness increased over time had a dementia risk roughly double that of those with stable sleep patterns.
The study authors noted: “Among community-dwelling women in their 80s, those with increasing 24-hour sleepiness over five years had doubled dementia risk during that time. Change in multidimensional 24-hour sleep-wake activity may serve as an early marker or risk factor for dementia in oldest old women.”
Other studies have also explored the link between sleep and dementia. A 2016 study in Alzheimer’s and Dementia journal found that high or low sleep duration increased the risk of cognitive impairment and dementia.
Meanwhile, a 2021 study in Nature Communications journal revealed that shorter sleep duration in middle age was associated with a higher dementia risk. The NHS highlights the following as “common” early signs of dementia:
- Struggling with familiar daily tasks, such as getting confused about change while shopping
- Trouble following conversations or finding the right words
- Memory loss
- Confusion about time and place
- Difficulty concentrating
- Mood changes
If you or someone you know is showing signs of dementia, it’s recommended to consult with a GP.