Association Between Sleep Quality and Falls: A Nationwide Population-Based Study from South Korea

Purpose: There are few large studies evaluating the association between sleep quality and the risk of falls. We aimed to determine the independent effect of poor sleep quality on an increased risk of falls using a large-sample dataset. Methods: We conducted a retrospective, cross-sectional study using population-based data from the 2018 Korean Community Health Survey on 201,700 participants. Sociodemographic, mental health-related, and physical health-related variables as well as sleep quality evaluated by the Pittsburgh Sleep Quality Index (PSQI) were compared between 2499 fallers who have experienced at least one fall during the past 12 months and 199,201 non-fallers. Multivariable logistic regression was performed to identify sleep quality variables significantly associated with an increased risk of falls. Results: Fallers had poorer sleep quality (PSQI score >5) and higher scores for global PSQI and individual PSQI components than did non-fallers (all p < 0.001). Multivariable logistic regression adjusted for potential confounders including socioeconomic, physical health-related, and mental health-related variables showed that an increased risk of falls was associated with poor sleep quality (odds ratio [OR] 1.30, 95% confidence interval [CI] 1.19-1.42). Subgroup analyses by age revealed that poor sleep quality was significantly associated with an increased risk of falls in all three adult age groups. Multivariable logistic regression using the seven PSQI components revealed that an increased risk of falls was associated with short sleep duration (OR 1.14, CI 1.09-1.20), increased sleep disturbances (OR 1.30, CI 1.16-1.46), and increased daytime dysfunctions (OR 1.21, CI 1.08-1.13). Conclusion: Poor sleep quality caused by short sleep duration may be a principal risk factor of falls in adult populations. Increased sleep disturbances and daytime dysfunctions may also contribute to an increased risk of falls. Our results have clinical and public health perspectives that increasing sleep duration and reducing daytime dysfunctions and sleep disturbances could mitigate unintentional falls.