[Sleep disorders in elderly, the sleep apnea syndrome in particular: are they a cause of insomnia? A review of literature].

In this publication a review is presented based on the findings resulting from sleep-wake investigations searching for sleep disorders associated with insomnia in relatively healthy elderly. 44 Relevant journal articles published between 1980-1998 were found. The four most important sleep disorders which can be accompanied by sleeplessness in relatively healthy elderly people are periodic leg movements disorder (PLM), restless legs syndrome (RLS), REM sleep behaviour disorder (RBD) and sleep apnea syndrome (SAS). Of these disorders, sleep apnea and periodic leg movements occur most frequently, in a quarter of the elderly. The latter, however, seldom complain about sleeplessness. Within the category of older people disorders characterized by movements during sleep increase significantly with age, nightly respiration disorders do not. SAS, PLM and RBD appear most frequently in men and RLS in women. The disorders characterized by movements during sleep (especially RLS and RBD) are often accompanied by sleeplessness. SAS, however, is more closely associated with day-time sleepiness than with sleeplessness. No combination of demographic variables and symptoms allows a reliable prediction of these sleep disorders. Fortunately, these disorders are not a major threat to the health of older people.