A person’s age is one of the many factors that influence how much sleep they need every night. The Canadian 24-Hour Movement Guidelines for Adults recommend 7 to 9 hours of good-quality sleep each night for adults between 18 and 64 years old, and 7 to 8 hours for adults over the age of 65.
Babies, children, and adolescents need more sleep than adults do. Newborns may sleep for as much as 18 hours over a 24-hour period, often in spells. Sleep plays an important role in an infant’s physical and mental development, and it is associated with certain cognitive functions (such as language and memory).
The amount of sleep a person needs isn’t the only aspect of sleep that changes with age. As people grow older, sleep patterns often shift and sleep architecture — the basic structure of an individual’s sleep — can be altered. A number of other factors (such as underlying health conditions) are also known to affect sleep in older people.
How is sleep affected by aging?
Circadian rhythms
Circadian rhythms are internal bodily processes that perform a number of functions, including regulation of the sleep-wake cycle. The suprachiasmatic nucleus (SCN) — a structure inside the brain’s hypothalamus — acts as the central pacemaker of the body’s circadian system and is responsible for managing most circadian rhythms. As people age, the SCN’s function begins to deteriorate. This can interfere with circadian rhythms, directly influencing when a person feels tired or alert.
According to research from the Canadian Medical Association Journal, there is typically a phase advance in the circadian sleep cycle of older people — meaning that older people tend to go to sleep earlier in the night but also wake up earlier in the morning. Teenagers, on the other hand, might experience a delayed circadian clock phase. It is this, in part, that can contribute to a sleep pattern that involves staying up later and waking up later.
Sleep architecture
Sleep architecture refers to the way a person typically cycles through the four stages of sleep. Stage 4 is when rapid eye movement (REM) sleep takes place, while stages 1, 2, and 3 are associated with non-REM sleep. As people age, their sleep architecture can change — research indicates that older adults stay in the earlier, lighter stages of sleep for longer and spend less time in stages 3 and 4, the later, deeper stages of sleep. This altered sleep architecture can cause older people to awaken more often throughout the night and can lead to poorer sleep quality.
Hormone production
Melatonin is a hormone produced by the brain that plays an important role in sleep. Natural levels of melatonin in the blood are highest at night because the production and release of melatonin in the body are linked to the time of day, increasing with exposure to darkness and decreasing with exposure to light. As a person grows older, their body produces less melatonin, which may contribute to problems with falling or staying asleep.
Health conditions
Mental and physical health conditions that can affect sleep in older people include depression, anxiety, heart disease, and diabetes. Health issues with symptoms that result in discomfort or pain may also have an impact on sleep quality in older people, and certain medications can trigger side effects that interrupt sleep.
The risk of Alzheimer’s disease and related types of dementia rises with age, and these conditions can lead to problems with sleep — research suggests that approximately one-quarter of people with dementia experience sleep disturbances. The symptoms of dementia can make it hard for a person to go to bed or stay in bed, and this may make it difficult for them to maintain good sleep quality and a consistent sleep pattern.
Concerns about ongoing sleep loss due to health conditions or medication should be shared with a doctor.
Common sleep issues in older people
According to the Public Health Agency of Canada, 1 in 4 adults aged 65 to 79 years are not getting enough sleep. Sleep disorders can be experienced by people of all ages, but there are certain sleep problems that may be more likely to arise or worsen as a person ages.
Insomnia is a sleep disorder characterized by difficulty falling or staying asleep, often leading to symptoms the next day. Symptoms of insomnia include daytime drowsiness, mood changes, and problems with concentrating or remembering. Insomnia is one of the most common sleep disorders in older people, with research from 2018 indicating that the overall prevalence of insomnia symptoms ranges from 30% to 48% in the elderly.
Additionally, physical changes in the urinary system as a person gets older can lead to more bathroom visits throughout the night, which can be disruptive to sleep. Studies suggest that nighttime urination (known as nocturia) is believed to affect a considerable proportion of the older population.
There are a number of steps that can be taken at home to help an older person with sleep problems. Practising good sleep hygiene — such as sticking to a consistent bedtime and ensuring the sleeping environment is dark, quiet, and comfortable — may promote better sleep and reduce the risk of sleep disturbances. Chronic or severe problems with sleep that affect a person’s day-to-day life should be addressed by a doctor, who can help identify any underlying conditions and provide guidance and treatment.