Disrupted sleep and circadian patterns in frontotemporal dementia.

BACKGROUND: A study of the pattern of Sleep/Wake disturbance in frontotemporal dementia (FTD). METHODS: Sleep diaries and prolonged actigraphy were used to record the activity, sleep and wake of 13 patients with a clinical diagnosis of FTD. These were compared with diaries and actigraphy from normal age/sex matched controls and also to a population with probable Alzheimer's disease (AD). RESULTS: There was significant sleep/wake disturbance in FTD. This occurred throughout the course of the illness and the nature of the sleep disturbance was different to patients with AD. FTD subjects showed increased nocturnal activity and decreased morning activity compared with controls, suggesting possible phase delay. Sleep diary data confirmed decreased sleep efficiency and decreased total sleep in all FTD patients. CONCLUSIONS: We describe significant sleep disturbance in non-institutionalized patients with FTD and suggest that early sleep disturbance may help differentiate between FTD and AD.