Association of Cognitive Function, Quality of Life, and Sleep Disorders in Children With Depression

Background: Children with depression frequently experience sleep disorders, which may significantly impact their cognitive function and quality of life. Investigating the relationship between sleep quality, cognitive performance, and quality of life in this population is essential for developing targeted interventions. Methods: From February 2022 to January 2024, 78 children diagnosed with depression at the Hunan Children's Hospital were assessed using the 17-item Hamilton Rating Scale for Depression (HAMD-17). Based on their HAMD-17 scores, participants were categorized into mild, moderate, and severe depression groups, with 26 children in each group. Sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI), cognitive function was assessed via the Wisconsin Card Sorting Test (WCST), and quality of life was measured using the 36-item Short Form Health Survey (SF-36). Correlations between PSQI, WCST, and SF-36 scores were analyzed for all groups. Results: Compared to the control group, the depression group of children with depression had significantly higher levels of depression and significantly lower levels of quality of life, sleep quality, and cognitive function (p < 0.05). Further analysis showed that sleep quality in children with depression worsened with increasing severity of depression, as evidenced by a gradual increase in PSQI scores (p < 0.05). Cognitive function assessment (WCST scores) revealed that with increasing depression severity, the number of classifications completed by children decreased, while the total number of errors, perseverative errors, and non-perseverative errors all significantly increased (p < 0.001). Quality of life assessment (SF-36 scores) showed that increasing depressive symptoms significantly affected the quality of life of children, with an overall significant decrease in scores (p < 0.05). Correlation analysis further revealed that cognitive function was closely related to sleep quality in children with depression. Specifically, the number of classifications completed was significantly negatively correlated with PSQI scores (r = –0.5534, p < 0.0001), while the total number of errors, perseverative errors, and non-perseverative errors were all significantly positively correlated with PSQI scores (r = 0.6769, 0.6988, and 0.6937, respectively, all p < 0.0001). In addition, four dimensions of quality of life (social function, physical function, role function, and cognitive function) were all significantly negatively correlated with sleep quality (r = –0.6866, –0.5309, –0.5823, –0.5698, respectively, all p < 0.0001). Conclusion: Poor sleep quality in children with depression is positively correlated with poor cognitive function and poor quality of life. Routine evaluation of sleep disturbances in this population can provide critical insights for timely intervention and management.