Clinical Diabetology · Aug 26, 2026
Glycemic Control and Cognitive Function in Dysglycemia: A Mediation Analysis of Depressive Symptoms Using NHANES 2011–2014
By Qian H, 毛 胜
Objective: To explore how depressive symptoms mediate the relationship between glycemic control and cognition among people with prediabetes and diabetes. Methods: A weighted multiple linear regression model was used to explore the relationship between diabetes status and cognitive function. A mediation model was used to analyze the mediating role of depressive symptoms. Results: After full adjustment, higher glycated hemoglobin (HbA1c) values were associated with higher depression scores (β = 0.34; 95% CI = 0.02 to 0.65; p = 0.039) and poorer cognitive performance on the Digit Symbol Substitution Test (DSST; β = −1.10; 95% CI = −2.10 to −0.11; p = 0.034). Higher depressive symptom scores were associated with poorer cognitive performance on the Consortium to Establish a Registry for Alzheimer’s Disease Word-Learning subtest (CERAD-WL; β = −0.10; 95% CI = −0.20 to 0.00; p = 0.048), Animal Fluency Test (AFT; β = −0.14; 95% CI = −0.23 to −0.05; p = 0.009), and DSST (β = −0.54; 95% CI = −0.80 to −0.27; p = 0.002). Depressive symptoms mediated 9.05% of the total effect of HbA1c on cognitive performance on the DSST. Conclusions: Depressive symptoms partially mediate the relationship between glycemic control and cognitive impairment in people with prediabetes and diabetes. These findings suggest that integrated management — combining glycemic control with mental health screening for depressive symptoms — may be more effective in delaying cognitive decline than glycemic management alone.