and Spain, and Japan has the highest aging rate of 28% [1].Older adults have many oral and dental health issues, such as tooth loss, periodontitis, decreased motor dysfunction, malnutrition, and dysphagia, as well as sleep disorders. Due to complications and age-related changes, sleep quality decreases in older adults. Obstructive sleep apnea (OSA), which substantially reduces sleep quality, is a common disorder that occurs in 3% of women and 10% of men aged 30-49 years, and in 9% of women and 17% of men aged 50-70 years [2]. Older adults are at a markedly higher risk of developing OSA owing to age-related increases in its incidence. Although mandibular advancement devices (MAD) are recommended for OSA, many factors, including the presence of other sleep disorders in conjunction with OSA, the use of medications that affect sleep apnea, and a lack of teeth (which are needed to support MAD), make this treatment difficult in older adults.This narrative review discusses important information for dentists practicing dental sleep medicine in older adults. As limited information is currently available on older adults with frailty, we did not discuss this population in the review.
Sleep physiology in older adultsAge-related changes in brain function affect sleep and wakefulness. Sleep physiology differs between older and younger adults, with sleep disturbances occurring frequently in older adults. Decreased sleep quality in older adults considerably impacts their quality of life. Older adults have lower sleep efficiency as they spend more time lying in bed and less time sleeping than younger adults[3], thereby reducing the amount of deep sleep [4].The total amount of sleep gradually decreases with age. Sleep duration is approximately 8 h in late adolescence and slowly decreases to approximately 6 h in older adults aged ≥75 years. In older adults, the time to fall asleep and wake up is slightly earlier because of the advanced phase of the circadian rhythm and core body temperature [5]. It is important to note that these age-related physiological changes in older adults may affect the quality and quantity of sleep. Thus, questionnaires to understand their sleep cycles are important.