Mohammed T. Abou-Saleh

Principles and Practice of Geriatric Psychiatry.Editors: Professor John R. M. Copeland, Dr Mohammed T. Abou-Saleh and Professor Dan G. BlazerCopyright & 2002 John Wiley & Sons LtdPrint ISBN 0-471-98197-4 Online ISBN 0-470-84641-0113bSleep and Ageing:Disorders and ManagementHelen ChiuChinese University of Hong Kong, People’s Republic of ChinaSleep complaints are very common in the elderly, with up to 40%being affected by insomnia. Further, a disproportionately largenumber of prescriptions of sedative–hypnotics are given to elderlypeople. Sleep disturbances in the elderly may be the result ofphysiological changes with the ageing process, poor sleep hygiene,medical and psychiatric conditions (particularly depression) leadingto secondary sleep disturbance, and primary sleep disorders 1 .A number of changes in sleep characteristics and architectureoccurs with ageing. In general, the older person takes more time tofall asleep, has more awakenings and less efficient sleep, as well asmore napping in the daytime. Moreover, the older person tends togo to bed early and rise early, reflecting a phase-advanced rhythmof the sleep–wake pattern. In addition, there is a decrease in slowwave sleep and rapid eye movement (REM) sleep but an increasein light sleep, i.e. stages 1 and 2 of NREM sleep 1–3 .Inadequate sleep hygiene includes poor sleep habits andengaging in sleep-incompatible behaviour 4 . Excessive time inbed, irregular hour of going to bed, lack of exercise, excessivecaffeine intake, alcohol withdrawal and noisy environment are allfactors that might influence sleep.Numerous medical conditions can lead to sleep disturbances,especially when pain is a significant feature. In the elderly,dementia is a common cause of sleep disturbance. In Alzheimer’sdisease, there is a decrease in slow-wave sleep and REM sleep,with increased fragmentation of sleep. A disrupted sleep–wakecycle is frequently found. Agitation and confusion in the eveningand at night (sundowning) may also occur in some patients 5 .As for primary sleep disorders, sleep apnoea, REM sleepbehaviour disorder and periodic leg movement during sleep(PLMS) are the ones with increased prevalence in the elderly, andwill be dealt with in this chapter.SLEEP APNOEAA period of apnoea is defined by a cessation of breathing for 10 sor more, whereas a hypopnoea period is a 50% reduction in therespiratory depth for 10 seconds or more. Sleep apnoea ischaracterized by recurrent episodes of apnoea and hypopnoeaduring sleep, and is usually associated with oxygen desaturation inthe blood 6 .There are two main types of sleep apnoea, obstructive andcentral. Obstructive sleep apnoea is the more common form.Cardinal features are loud snoring and excessive daytimesleepiness. Associated features include headache, insomnia,apnoea observed during sleep, excessive movements duringsleep, cognitive impairment, personality changes and enuresis.Physical problems include systemic hypertension, pulmonaryhypertension and cor pulmonale 6 , which might explain whysleep apnoea is associated with an increased mortality due tocardiovascular events.The exact prevalence of sleep apnoea is unknown but it isestimated that about 2–4% of the general population meetminimal criteria for obstructive sleep apnoea 7 . Its frequencyincreases with age, reaching a maximum between 50 and 70 yearsof age, and there is a male predominance. In the elderly,prevalence rates of 26–73% have been reported in variousstudies 8 . This shows that disordered breathing is a commonproblem in the elderly. However, a major unresolved issue iswhether sleep apnoea is a less pathological condition in theelderly. Studies in clinical populations have shown that disturbedrespiration during sleep in the elderly has minimal associationwith mortality and morbidity, while epidemiologic studies in theelderly have suggested otherwise 2 . Pending further studies toclarify the issue, older people with symptomatic sleep apnoeaprobably should be treated in the same way as younger patients.In the management of sleep apnoea, general measures includeweight reduction and avoidance of alcohol and benzodiazepinesbefore bedtime. In the majority of patients with sleep apnoea,continuous positive airway pressure (CPAP) during sleep is thetreatment of choice. Surgical treatment may be indicated forpatients with specific upper airway abnormality who have failedCPAP therapy or did not want CPAP for various reasons, such asfrequent travelling 9 .REM SLEEP BEHAVIOUR DISORDER (RSBD)This is a recently described parasomnia 10 . Presenting features areusually excessive motor activity during sleep, which may lead torepeated injuries to the patients or their bed-partners. Patientsmay talk or shout aloud in sleep, accompanied by vigorous limbmovements, walking, falling out of bed, or carrying out variousactivities in their dreams. After awakening, patients may recalldreams that coincide with their motor activities. This suggests thatthe motor activity in sleep is a form of dream enactment. Somepatients resort to various measures to protect themselves frominjury, like tying themselves to the bed or putting a mattress onthe floor. In addition, the nature of their dreams may change overthe years, becoming very vivid and action-packed 11 . The diagnosisof RSBD should be considered in elderly people presenting withsleep-related injury or violence.Principles and Practice of Geriatric Psychiatry, 2nd edn. Edited by J. R. M. Copeland, M. T. Abou-Saleh and D. G. Blazer&2002 John Wiley & Sons, Ltd