Association between loneliness, sleep behavior and quality: a propensity-score-matched case-control study

Objective: To explore the influence of loneliness on sleep behavior and sleep quality based on propensity score-matched samples in Southwest China. Methods: Individual-level data were obtained from a Southwest China cohort study. Participants who felt lonely were matched with those who did not with propensity scores on the basis of age, gender, socioeconomic factors, physical exercise and social connection level. Sleep behavior (onset and offset timing), sleep quality (sleep latency, nocturnal awakenings and subjective sleep quality), and daytime function (daytime sleepiness and fatigue) were assessed with the Pittsburgh Sleep Index Scale (PSQI) and compared between the two groups. The data were collected between May 2019 and December 2019, and data analyses were completed in April 2021. Results: A total of 11,696 participants were included, and 824 out of 839 participants who felt loneliness were statistically matched with 824 participants who did not. Analyses of the matched samples showed that sleep onset and offset timing were similar between those who felt lonely and those who did not (p = 0.110 and p = 0.751, respectively). Sleep latency was longer in those who felt lonely (26.84 [0.9] vs. 35.52 [1.2] min, p < 0.001) than in those who did not. Furthermore, participants who felt lonely tended to have poor subjective sleep, a higher frequency of nocturnal awakenings, daytime sleepiness and fatigue (all p < 0.001). Conclusions: Loneliness was associated with extended sleep latency, increased nocturnal awakenings, and reduced subjective sleep quality and daytime function but was not associated with sleep behavior, including sleep onset and offset timings. (c) 2021 Elsevier B.V. All rights reserved.