Environmental factors related to sleep latency among inpatients in rehabilitation wards according to functional independence measure cognitive scores.

Abstract

No study has investigated sleep-related environmental factors in patients according to their functional independence measure (FIM) cognitive scores. The aim of this study is to examine the associations between environmental factors such as noise and sleep latency according to the FIM cognitive scores among inpatients in rehabilitation wards. This is a prospective longitudinal study. This study measured the sleep state using a bed-based actigraphy, environmental data from Environmental Sensor®, and medical record information of 33 inpatients in the rehabilitation wards during 2018. A linear mixed-effect model was used to analyse the associations between sleep latency and environmental factors. Participants were grouped according to high or low FIM cognitive scores. The average patient age was 77.2 ± 10.9 years, and 48.5% were male. In the high FIM cognitive score group, the loudness and frequency of noise exceeding 40 dB during sleep latency were significantly associated with sleep latency. In the low FIM cognitive score group, only the noise frequency was associated with sleep latency, and intra-individual variance was larger than that of the high group. These findings suggest that providing night care with attention to subdued noise is important, particularly for patients with low cognitive functional independence levels measured by the FIM cognitive score.