Exposure to light and noise at night, and sleep quality in community-dwelling older adults: a cross-sectional study

We aimed to investigate the levels and sources of nighttime light and noise exposure in community-dwelling older adults and explored their associations with sleep quality.

A total of 2978 participants ≥ 65 years old from the 2023 survey of Yiwu Elderly Cohort were included in this cross-sectional study. Nighttime light and noise exposure and sleep quality information were collected by questionnaires. Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep quality. Log-binomial regression models were performed to evaluate the associations between different levels and sources of nighttime light and noise and sleep quality.

Among the 2978 participants (median age 72.0 years (interquartile range [IQR], 68.0-76.0 years), 49.8% men), 39.7% (n = 1181) were classified as having poor sleep quality (PSQI > 5). Significant associations were found between nighttime light and noise and poor sleep, with prevalence ratio (PR) of 1.14 (95% confidence interval [95% CI] 1.04, 1.26) for light and 1.15 (95% CI 1.03, 1.30) for noise. Specifically, light or television on in the room, light outside the room, and noise from the room, traffic and public place, were negatively associated with sleep quality. Further exploring the associations with PSQI components, nighttime light tended to increase the risk of low sleep efficiency, long sleep latency and sleep disturbances.

Nighttime light and noise exposure are associated with poor sleep quality in older adults. Further interventional studies should explore whether creating a dim and quiet sleeping environment can help maintain good sleep quality in older adults.