Disrupted daily activity/rest cycles in relation to daily @entity701 rhythms of home-dwelling XXXX with early @entity195 .

@entity1 @entity1949 @entity303 @entity701 @entity195 @entity393
Disturbed sleep cycles are the principal cause of institutionalization in @entity303 , and therefore represent a major clinical problem. They may arise from dysfunction within the circadian clock of the hypothalamus that times and consolidates wakefulness, or from neuropathology in output pathways and/or target sites of the clock specifically controlling sleep and wakefulness. To determine the relationship of disturbed activity cycles to other circadian clock-controlled rhythms, cross-sectional and longitudinal actigraphy and serial sampling of saliva were used to compare the impact of early @entity195 on activity/rest and @entity701 rhythms in home-dwelling subjects. Mildly demented subjects had daily activity rhythms comparable to those of healthy age-matched subjects. Moderately demented subjects exhibited a range of disturbances of the activity/rest cycle, with reduced stability, @entity1949 and @entity393 . Within the moderately demented group, however, the degree of circadian disruption was not correlated with the individual severity of @entity303 . All groups of subjects, mild, moderate with normal activity cycles and moderate with abnormal activity cycles, exhibited robust daily profiles of salivary @entity701 , with highest levels in the morning (08:00 h) and an evening nadir (20:00-24:00 h). Salivary @entity701 levels tended to be higher in the moderately demented subjects in the afternoon, but this effect was not specific to those with abnormal activity/rest patterns. The actimetric data confirm that deterioration of activity/rest cycles is a common and progressive feature in home-dwelling Alzheimer's @entity1 , occurring early in the disease but after the measurable onset of @entity303 . The maintenance of highly rhythmic daily @entity701 profiles in association with disturbed activity profiles, both on an individual and on a group basis, demonstrates that loss of circadian control to activity/rest cycles is not a consequence of global circadian disruption in early @entity303 . Rather, pathology may develop in discrete elements of the circadian clockwork and/or its output systems that control activity/rest, sleep and wakefulness. Further characterization of this pathology will facilitate more effective management of sleep patterns in home-dwelling demented @entity1 .
