Differential circadian rhythm disturbances in men with Alzheimer disease and frontotemporal degeneration

Background: Caregiver Exhaustion is a frequent consequence of sleep disturb ance and rest-activity rhythm disruption that occurs in dementia. This exha ustion is the causal factor most frequently cited by caregivers in making t he decision to institutionalize patients with dementia. Recent studies have implicated dysfunction of the circadian pacemaker in the etiology of these disturbances in dementia. Methods: We studied the activity and core-body temperature rhythms in a coh ort of 38 male patients with a clinical diagnosis of probable Alzheimer dis ease (AD) approximately 2 years before death. These patients were later giv en a confirmed diagnosis of AD (n=23), frontotemporal degeneration (FTD) (n =9), or diffuse Lewy body disease (DLB) with mixed AD or FTD pathologies (n =6) after autopsy and neuropathological Examination. Physiological rhythms of patients with AD and FTD were then compared with a group of normal, elde rly men (n=8) from the community. Results: Alzheimer patients showed increased nocturnal activity and a signi ficant phase-delay in their rhythms of core-body temperature and activity c ompared with patients with FTD and controls. The activity rhythm of FTD pat ients was highly fragmented and phase-advanced in comparison with controls and apparently uncoupled from the rhythm of core-body temperature. Conclusions: Patients with AD and patients with FTD show different disturba nces in their rhythms of activity and temperature compared with each other and with normal elderly patients.