[Sleep disturbance in elderly patients with dementia at home and the factors associated with its identification: An observational study].

AIMS

The purpose of this study was to objectively quantify the sleep of elderly patients with dementia at home using a device and to investigate the factors associated with its identification.

METHODS

Sixteen patients (6 males [37.5%], 84.1±4.7 years old; and 10 patients with mild dementia [62.5%]) and their family caregivers who were using outpatient memory clinics and home-visiting nursing station in Japan were included. Demographic and clinical data of the patients and their family caregivers, subjective perceptions of patients' sleep, family caregivers' Zarit care burden, and whether or not they were aware of patients' sleep problems were determined. Nighttime sleep parameters were collected for one week using a non-wearable actigraph. Sleep parameters were compared with patients' subjective views and family caregivers' observations to investigate factors indicative of sleep disturbance.

RESULTS

Nighttime sleep parameters for 1 week (mean) were follows: sleep efficiency, 77.2%±9.3%; asleep time, 442.3±99.9 minutes; sleep latency, 18.2±15.8 minutes; awake time, 105.1±69.7 minutes; and number of times leaving the bed, 4.6±3.8 (maximum of 29/night). A significant positive correlation was found between sleep efficiency and duration of dementia (r=0.53, p=0.046), while no correlation was found with dementia severity or Zarit care burden score. The agreement between the patients' complaints about sleep and sleep efficiency (75%) was 30.7%, and family caregivers' awareness of patients' nighttime awakening and bed-leaving was significantly associated with patients' incontinence (p=0.024) and a greater dementia severity (p=0.027).

CONCLUSIONS

Elderly dementia patients experienced sleep disturbance at home, such as nighttime awakening and associated bed-leaving; however, it might be difficult to identify these patients at an early stage based on their own complaints and observations by family caregivers. Identifying sleep problems at an early stage may thus require the use of objective measurement devices.