Associations of Glycemic Control with Cognitive Flexibility and Mental Health-Related Quality of Life in Type 2...

Cognitive flexibility, a core executive function, enables individuals to adapt to the behavioral demands of chronic disease management. Poor glycemic control, indicated by elevated glycated hemoglobin (HbA1c), may impair cognition, adherence, and quality of life in type 2 diabetes mellitus (T2DM). This study examined associations between glycemic control, cognitive flexibility, and HRQoL.

This cross-sectional study included 268 adults with T2DM recruited from a tertiary endocrinology clinic between March and September 2024. Eligible participants had been diagnosed within the past 10 years and maintained a stable regimen across their two most recent HbA1c assessments. Exclusion criteria included major comorbidities, psychiatric or neurological treatment, and pregnancy. HbA1c values were obtained from medical records. Cognitive flexibility was assessed using the Cognitive Flexibility Inventory (CFI), and health-related quality of life with the 12-Item Short Form Survey (SF-12). Group comparisons (adequate vs poor glycemic control), Pearson's correlations and multiple linear regression analyses adjusting for potential confounders were conducted using IBM SPSS Statistics. An a priori power analysis was performed using G*Power, confirming a sufficient sample size (power = 0.91).

Of the 268 participants, 55.9% had poor glycemic control (HbA1c ≥ 7%). Compared with adequate control, those with poor control scored lower on CFI-Alternatives (p = 0.017, d = 0.51) and SF-12 mental component summary (p = 0.023, d = 0.56). Smaller but significant differences were found for CFI-Total (p = 0.037, d = 0.33) and SF-12 physical component summary (p = 0.042, d = 0.21). HbA1c correlated inversely with CFI-Alternatives (r = -0.228, p = 0.035), CFI-Total (r = -0.208, p = 0.038), and MCS-12 (r = -0.247, p = 0.022). These associations were clinically meaningful and remained significant in multiple linear regression analyses.

Poor glycemic control is associated with reduced cognitive flexibility and impaired HRQoL, particularly in the mental domain, among individuals with T2DM. The role of cognitive flexibility in treatment adherence warrants further investigation.