Objective To examine the association between sleep and depressive symptoms among community-dwelling older adults and whether loneliness mediates this association.

Methods Using a multistage sampling approach, we enrolled participants aged 60 years or older from two communities in Chengdu, China. A questionnaire was used to collect basic information, including age, sex, etc., from the participants. In addition, loneliness, depressive symptoms, and sleep quality were assessed using a short-form University of California Los Angeles Loneliness Scale (ULS-8), the 10-item version of Center of Epidemiologic Studies Depression Scale (CESD-10), and the Pittsburgh Sleep Quality Index (PSQI), respectively. The Spearman rank correlation coefficient was employed to assess the correlations among social sleep, loneliness, and depression symptoms. Generalized structural equation modeling was used to assess the mediating effect of loneliness between sleep and depressive symptoms.

Results Of the 1377 participants, 32.03% (441) experienced loneliness and 30.57% (421) had depressive symptoms, with the median and interquartile range of their sleep quality being 6 (3, 9). Correlation analysis revealed statistically significant associations between sleep quality, loneliness, and depressive symptoms (P < 0.001). Generalized structural equation modeling analysis revealed that loneliness had a partial mediation effect on the association between sleep quality and depressive symptoms (b = 0.075; 95% CI, 0.025-0.125; P < 0.05), accounting for 44.38% of the total effect (95% CI, 0.258-0.630; P < 0.001).

Conclusion Poor sleep quality is associated with a higher risk of depressive symptoms in community-dwelling older adults, with loneliness mediating the association. Further research on improving the sleep quality to mitigate depressive symptoms in older adults is warranted. Special attention should be given to older adults experiencing both poor sleep and loneliness.