Olive Cooke was an asset to society. Even in her nineties, she could be found selling poppies ahead of Remembrance Day to raise money for injured servicemen and women. Yet, it was reported in the press that on May 6, 2015, at age 92, her body was found at the bottom of a gorge — Cooke had taken her own life. A suicide note for her family reported that her life had become unbearable. Among other difficulties, including depression and ill health, she was no longer able to sleep, getting very few hours a night — and she couldn’t take it anymore.
Her story touched people all over Britain, and the prime minister issued a statement about her death. The inclusion of sleep among the issues that she dealt with was relatable to many.
During adolescence, bedtime moves to later, and it becomes much harder to wake up early in the morning. Flip this and you have the typical sleep of an older adult: It’s hard to stay up late and bedtime moves earlier. These differences between us might make good evolutionary sense — if there is always someone awake and able to watch over the group, we’re more likely to stay safe. This has been referred to as the “poorly sleeping grandparent” hypothesis: Older group members are up early or sleepless at night and will watch over the others. The hope is that the patterns of sleep in younger people will allow them to repay the favor, so there is always someone who is awake.
Sleep stages also change over time, and as we enter the golden years of our lives, we experience lighter sleep. But with increasingly light sleep comes an inevitable decrease in the other stages. We get less REM and deep, slow-wave sleep. It has been proposed that a reduction in slow-wave sleep — which is important for our physical and mental restoration — could even signify an age-related deterioration of the central nervous system.
As we age, we typically spend a greater proportion of the night awake — perhaps lying in bed with just our thoughts. Sleep apnea and restless legs syndrome are also common in older adults.
When I talk to Marco, a 79-year-old retired university lecturer, about his sleep patterns, he tells me, “I prefer to go to bed around 10 p.m. I never wake fewer than three times — to urinate — before sleep ends around 5.30 a.m. The longest time I sleep is three hours, although I had a single record-breaking four-hour phase a few months ago.” When I ask him how this relates to his peers, he tells me that he rarely discusses his sleep with them, but on the odd occasion that he does, they nod knowingly as if members of a secret club.
For some, there is the loss of a partner and a warm bed turns cold. Sleep disruption caused by tussles for the duvet gives way to that due to a newfound stillness.
So, why do these changes occur? Sleep is brought about by a complex dance between different areas of the brain vying to turn each other on and off in order to bring about sleep and wakefulness. In older adults, death of neurons in brain areas such as the ventrolateral preoptic (VLPO) nucleus of the hypothalamus, an area centrally important in bringing about sleep, could therefore lead to problems when hitting the hay.
Changes in behavior are also likely to lead to problems. Of course, the behavior of many older adults is far from stereotypical, and we live in a society where youths set up multibillion-dollar businesses from their bedrooms and centenarians run marathons. However, there are also more stereotypical trends that may explain certain sleep changes. These include spending more time at home or, for some, in care homes. With that might come reduced exercise and exposure to light, coupled with increased opportunities for napping.
Spending long periods of time at home and not seeing friends, family, and neighbors could result in poor-quality relationships. This could in turn lead to loneliness — a complaint that is common in older adults. Loneliness — something we have all felt at some point — involves feeling that our social network is not up to scratch, which can reduce feelings of safety. Feeling safe is important when it comes to our sleep, as it’s unwise to lose consciousness if we think harm might come to us, so perhaps it is perceived vulnerability that links loneliness and poor sleep quality. Our sleep becomes fragmented, allowing us to stay alert to danger.
But alterations in behavior do not explain all the sleep changes experienced in older adults. How do they account for poor sleep experienced by the “glammy grannies” who are members of tennis clubs and are drowning in friends and social activities? They could teach people half their age a thing or two about getting exercise and exposure to sunlight and living life to the fullest, yet some still struggle terribly with their sleep. So, which aspects of aging, other than lifestyle, might explain these sleep alterations?
Hormonal changes are one possibility, especially in women. Women’s estrogen and progesterone levels plummet during menopause, which usually occurs earlier in adulthood, at around the age of 50. It can lead to symptoms such as hot flushes, anxiety, and depression — and all these things can seriously impair a good night’s sleep.
Marco, the retired university lecturer, suggests that I talk to his wife, Maria, a sculptor, about her sleep. She has recently turned 75 and describes menopause affecting her sleep in a way that seems to chime well with reports from others. She tells me, “My joints felt more painful, and particularly so at night. I would wake up feeling intense heat around my face and neck…Even in the coldest of nights, I threw off all my covers and still felt internally hot, though aware that my feet were freezing.”
Exploring this topic, a study of women aged 40 to 59 focused on self-reported sleep duration and quality in relation to menopausal status. Whereas just 33 percent of premenopausal women claimed to sleep for fewer than seven hours a night, that figure leaped to 41 percent in postmenopausal women.
Postmenopausal women were also more likely to report sleep problems and to wake up feeling unrefreshed compared with premenopausal women. Maria’s description is in line with the research findings, and she ends by telling me, “I have never managed to regain my good sleeping habits. Sleep has become something I do reluctantly. The pleasure of sleep is something of the past.”
Physical ailments are also linked to sleep quality and may add up over the course of one’s life or appear at a greater rate as we age. Cancer, diabetes, Alzheimer’s, Parkinson’s, and enlarged prostate are just some of the problems that are more common as we grow older — and have been linked to poorer sleep. The mechanisms linking these problems to sleep are diverse, but pain and discomfort, toilet trips during the night, as well as the impact of certain medications, are just some of the ways physical illness can disrupt our sleep.
Our entire bodies suffer with the aging process. However, one particularly interesting change concerns the eyes, the lenses of which begin to yellow. This is caused by a buildup of pigment over time and reduces the amount of blue light that is passed to our retinas. It’s even been suggested that older artists use more blue paint in their work for this very reason. Changes to the eyes provides one fascinating route by which the aging process may be linked to sleep, as it is this same blue light that is most significant in setting our internal clocks and can prevent our bodies from making the hormone melatonin when we look at our tablet or phone late at night. So, with a newly formed blue-light filter in our eyes, the light cues around us might become less useful in influencing sleep timing.
This period of life can also bring psychological challenges. Dealing with our own mortality or that of loved ones can come at a huge psychological cost. Perhaps unsurprisingly, scientific research shows that older adults who are grieving experience less sleep, and the rest they do get is of a poorer quality — an association mainly explained by feeling depressed.
So, it seems there are multiple reasons why sleep can become disrupted as we age — but which risk factors are most salient? A review published in 2016 compared risk factors. It found that rather than age itself, the greatest predictors of poor sleep in older adulthood were being female, feeling depressed, and being physically unwell. Older people falling into these categories — especially those falling into all three — might particularly need support to help them sleep well.
Yet, sleep at this stage of life is not all bad, and some people sleep very well. Others who report feeling overwhelmed during the busiest stages of their lives yearn for old age, when they are able to apply the brakes and enjoy a lie-in if they so choose. This portion of life is sometimes accompanied by fewer responsibilities and can allow us to banish the alarm clock, as well as enjoy new opportunities during the daytime. While sleep problems are common in older adults, they are certainly not an inevitable part of aging — and for those who do suffer, help may be found with advice from a physician.