Association of dietary fiber with subjective sleep quality in hemodialysis patients: a cross-sectional study in China

BACKGROUND: Poor sleep quality is a common problem among hemodialysis (HD) patients. Dietary fiber is a key component of a healthy diet and is beneficial for a variety of health outcomes; however, evidence of an association between dietary fiber consumption and subjective sleep quality has not been established among HD patients. Therefore, we determined the association between dietary fiber consumption and the subjective sleep quality in Chinese maintenance HD patients, taking into account fiber type and source. METHODS: Dietary intake was assessed with a validated food frequency questionnaire in a cross-sectional study including 741 maintenance HD patients between December 2021 and January 2022. The daily intake of dietary fiber was categorized into three groups. The lowest tertile was used as the reference category. Sleep quality of patients was accurately calculated using the Pittsburgh sleep quality index standard questionnaire. Multivariable logistic regression model and restricted cubic spline analysis were performed to assess the relationship between dietary fiber consumption and poor sleep quality. RESULTS: Compared with the lowest tertile group of dietary fiber intake, the highest tertile group had a lower prevalence of poor sleep quality. After adjustment for potential confounders, a higher intake of total dietary fiber (OR(tertile 3 (T3) to tertile 1 (T1))= 0.51, 95% CI: 0.31–0.85), total insoluble dietary fiber (OR(T3 to T1) =0.54, 95% CI: 0.33–0.89), and soluble dietary fiber in vegetables (OR(T3 to T1) =0.61, 95% CI: 0.40–0.93) were associated with a lower prevalence of poor sleep quality. Furthermore, significant linear trends were also observed (p < 0.05). No significant interactions were observed in subgroup analyses. CONCLUSION: A higher intake of dietary fiber was inversely associated with the poor sleep quality. These findings support the current recommendations that dietary fiber is essential for health and well-being. KEY MESSAGES: 1. This study was conducted because there was not prior evidence connecting sleep quality and dietary fiber consumption in hemodialysis patients. 2. In the present study a cross-sectional design was used to assess the association between dietary fiber consumption and poor sleep quality. 3. Intake of total dietary fiber, total insoluble dietary fiber, and soluble dietary fiber in vegetables were negatively associated with poor sleep quality among maintenance hemodialysis patients.