Many of us believe poor sleep is inevitable as we get older. Chronic pain, medication side effects, and more frequent middle-of-the-night trips to the bathroom affect the quantity and quality of our rest. That has implications not only for physical health, but for cognitive health as well, according to research presented at the Gerontological Society of America conference in November 2023.
Age-related sleep disruptions
While we don’t need as much sleep as we did as teenagers, most older people still need about seven hours of good-quality sleep each night, according to Katie Stone, an epidemiologist and sleep researcher at California Pacific Medical Center and the University of California, San Francisco.
However, as we age, our sleep tends to become shorter and more fragmented, with less time is spent in slow-wave and rapid eye movement (REM) sleep, Stone and other sleep researchers found. Additionally, other age-related sleep disruptions—including undiagnosed or untreated sleep apnea, as well as conditions such as depression and anxiety—can have a real impact on our brain health.
Sleep for better brain health
“Evidence suggests that sleep plays a role in clearing Alzheimer’s-linked proteins from the brain," said Stone. “In the presence of sleep disruption, those plaques, like beta amyloid, can accumulate and that's an early sign that somebody may be progressing toward Alzheimer's disease or dementia.” Additionally, poor sleep contributes to inflammation and metabolic dysfunction, which also are linked to cognitive decline or dementia.
Researchers are growing more comfortable directly linking poor sleep health with cognitive decline. “The evidence is growing that it could be that it very well be causal,” Stone said. What hasn’t been firmly established is whether treating sleep problems can effectively slow that down. Researchers are on the cusp of learning whether treating poor sleep can not only prevent or delay decline in cognitive function but also reduce falls or other negative health effects that happen as we get older. Her current research shows that getting more consolidated sleep, and having fewer awakenings, is better for the brain.
Stone, who has been researching sleep and older adults for decades, has also also found that women may be more sensitive to sleep disruptions than men. Women tend to have more complaints about sleep, and insomnia is more common in women.
“Insomnia is really more of a subjective report of sleep problems with symptoms that are disturbing to the individual during the day. It's not like an objective test that you do similar to sleep apnea,” Stone explained. Other researchers are investigating possible hormonal links to sleep quality and gender differences in sleep health.
Stone and her team studied 820 older adults who were enrolled in the Study of Muscle, Mobility and Aging (SOMMA) for changes in executive function and in global tests of cognition. Participants wore actigraphs—small wristwatch-size monitors—for a week, to measure variables like total sleep time and sleep efficiency. They found that people with greater sleep fragmentation, as well as weaker 24-hour sleep-wake rhythms, had significantly greater odds of cognitive impairment. In this analysis, total sleep time had no effect at all on cognitive test performance.
In a prior study, Stone and colleagues reported that over five years of follow-up, people who did not have dementia at the start of the study, but had poorer sleep quality, were more likely to develop dementia over the long term.
There are many reasons older adults might have disrupted sleep, according to gerontologist Dr. Leslie Kernisan, a clinical instructor in the UCSF division of geriatrics, and host of the Better Health While Aging podcast. Among them: breathing disorders, like sleep apnea or COPD; chronic heartburn or gastric reflux; arthritis; overactive bladder; neurodegenerative diseases like Alzheimer’s or Parkinson’s; and medication side effects, which can be a huge culprit.
Nearly 90% of people over 65 take at least one prescription daily, and more than a third (36%) are on five or more prescriptions. Many of these medications can impact sleep quality. It becomes a cycle—someone is prescribed sleep medications to get them through the night, which may have side effects like residual daytime grogginess. Then, they nap during the day, which then makes it more difficult to fall asleep at night. Certain sleep medications themselves can also increase risk of dementia by as much as 79%, according to another UCSF study.
In addition to what is now standard advice for better sleep, such as turning off electronic devices and making your bedroom as comfortable and dark as possible, Stone also suggests these strategies:
1. Work with a health provider to address sleep problems rather than just self-medicating
While some people swear by supplements like melatonin or use combination pain relievers/sleep aids, she says they often don’t work all that well and can lead to other issues, like increased risk of falls when getting out of bed. We also still don’t know some of the long term effects of using certain medications, and they could be harmful in the long term.
2. Consider cognitive behavioral therapy for insomnia symptoms
For people who stay on cognitive behavioral therapy over the long term, It's more effective and tends to have a more lasting effect than medications. It’s the first line of treatment for insomnia recommended by the American College of Physicians and other health organizations.
3. Don’t shy away from talking to your healthcare provider about your sleep issues
Many sleep disorders, like sleep apnea, can be diagnosed by your doctor and treated without medication.
4. Make sleep health a priority
Sleep is just as critical to older people as a balanced diet and regular exercise, Stone said. It may get overlooked as an inevitable negative aspect of aging, but it’s an equally important pillar of health, and you can do something about it.
