Depressive symptom as a mediator of the influence of self-reported sleep quality on falls: a mediation analysis

Abstract

Objectives: It is well known that sleep quality was associated with falls. This study aimed to examine whether the presence of depressive symptoms mediate the association of self-reported sleep quality with falls.Methods: Data of community-based study including 4,579 adults aged 60 years or older were analyzed. Information regarding sleep quality and falls was self-reported by participants using pre-designed questionnaires. The nine-item Patient Health Questionnaire (PHQ-9) without the sleep item was used to assess the presence of depressive symptoms. A bootstrapping approach was performed to explore whether the relationship between self-reported sleep quality and falls was partially mediated by depressive symptoms. The mediator was considered significant if the 95% confidence interval (CI) did not include 0.Results: Older adults with poor sleep quality had higher odds of falls than their counterparts with normal sleep. In the equation regressed falls on self-reported sleep quality and PHQ-9 score, the association between self-reported sleep quality and falls disappeared. Depressive symptoms partially mediated the association between self-reported sleep quality and falls based on the significance of indirect effect (β = 0.15, 95% bootstrap CI = 0.08, 0.22).Conclusions: The presence of depressive symptoms might partially mediate the association of self-reported sleep quality with falls among older adults.