Sleep becomes less efficient as you age (it becomes shallower and more fragmented), but that doesn't mean older people need less sleep. Quite the opposite. The National Sleep Foundation of the United States recommends between seven and eight hours of sleep daily for older adults. And sleeping less than those recommended hours, especially if we fall below the six-hour threshold, has an impact on our physical and mental health.
Although it is estimated that up to 80% of adults in Western countries may be sleep deprived, the experts consulted believe that socially we are increasingly aware of the importance of a good rest as a pillar of a healthy life; as well as the relationship between lack of sleep and the development of certain diseases such as cardiovascular, metabolic, certain types of cancer or mental health disorders. There is not as much awareness about the close relationship between sleep and cognition. However, sleeping well, as pointed out by Dr. Adriano Targa, researcher at the CIBER Biomedical Research Center, helps prevent a natural physiological process such as brain aging.
"During the sleep period, many processes are experienced, such as the elimination of toxic molecules caused by neuronal activity during wakefulness; the synthesis of proteins, enzymes and other molecules that perform various functions in the body; and also the consolidation of various types of memory. In this way, by sleeping well, we help maintain brain function and avoid phenomena associated with older age such as increased inflammatory processes, oxidative stress, and cognitive difficulties," says the member of the working group. of Cognition and Sleep of the Spanish Sleep Society (SES).
Her opinion is shared by Dr. Celia García-Malo, a neurologist specializing in sleep medicine, who points out that at the level of cognition, various studies have confirmed that sleep disturbances, fundamentally those that affect the structure of sleep, have a direct impact on various neuropsychological domains. “Sleep fragmentation and reduced deep sleep phase time are related to lower attention span, worse working memory and worse executive function,” maintains the member of the Spanish Society of Neurology (SEN).
García-Malo adds that rest also has a crucial role in memory and learning processes, which occur mainly during slow-wave sleep or deep sleep and REM sleep, two phases that physiologically reduce in percentage as as we age: “Some research describes how a greater reduction in the percentage of deep sleep phase as well as the fragmentation in this phase of sleep is related to greater brain deposits of beta-amyloid, the same substance that accumulates in an abnormal and pathological way in people who suffer from some types of cognitive impairment such as Alzheimer's.”
Scientific evidence, as Adriano Targa emphasizes, has confirmed in numerous studies that chronically poor rest can accelerate brain aging and lead to cognitive deterioration. “All of this can lead to physiological events such as an increase in inflammatory processes and oxidative stress, which are generally associated with older age, which can alter the connectivity between neurons and also generate neuronal death,” says the expert.
Targa with García Malo in pointing out that ultimately this lack of sleep is associated with a greater risk of developing dementia: “With the data available to date, it is considered that there is a bidirectional relationship between sleep and Alzheimer's disease. That is, the presence of sleep disturbances is associated with a greater risk of developing the disease, just as the disease itself can lead to alterations in this sense.”
Chronic sleep deprivation at older ages - removing the stressor of work from the equation - may be due to the social context (poor sleep routines) and personal context (presence, for example, of mental disorders) or the presence of illnesses. related to sleep. In this last sense, Targa highlights obstructive sleep apnea (OSA) as especially important, an extremely prevalent disorder whose incidence increases with age which, however, has a high rate of underdiagnosis.
A recent study, presented at the beginning of March within the framework of the Annual Meeting of the American Academy of Neurology, demonstrated precisely the impact of OSA on cognition since, according to its results, people who experience sleep apnea They are 50% more likely to also have memory or thinking problems. “These findings highlight the importance of early detection of sleep apnea," conclude the authors of the research. And their recommendation is not trivial, since as Adriano Targa adds, current scientific evidence indicates that obstructive sleep apnea, In the long term, it increases the risk of developing mild cognitive impairment and Alzheimer's by 85 percent: "Based on these data, it is logical to expect that the treatment of OSA could help in the prevention of Alzheimer's disease."
The increase with age in the prevalence of sleep disorders (the aforementioned obstructive sleep apnea and insomnia, among others), as well as the physiological changes that occur with aging and that impact rest, can lead to normalization of bad rest. According to experts, a big mistake. “I think the most valuable advice that can be given to all ages, but especially during aging, is not to normalize poor sleep,” says Celia García-Malo, who explains that not being able to maintain sleep for a sufficient number of hours or not perceiving a good quality of sleep are indicators that we may suffer from a sleep disorder.
“If you have any warning signs, you should consult a specialist, because on certain occasions it may be necessary to perform a test, such as a sleep study, to reach a diagnosis,” recommends the neurologist, who also highlights the importance of not self-medicating: “The Hypnotic drugs or over-the-counter remedies, rather than curing the disorder, can serve as “a band-aid,” and in addition to not solving the problem, they can sometimes produce undesirable adverse effects.”
Ultimately, in order to improve rest to preserve brain health, experts list some basic tips for good sleep hygiene, which include adequate exposure to natural light during the first hours of the day, exercising regular physical exercise, maintain more or less regular sleep schedules and dedicate the last hours of the day to disconnecting - also from screens - to promote falling asleep.
