Assessment of Anxiety and Depression Symptoms Following Insulin Initiation in Type 2 Diabetes: A 6-Month Prospective Observational Study

Abstract

Objective: To compare 6-month changes in anxiety and depression levels relative to metabolic trajectories between patients with type 2 diabetes newly initiated on insulin and an oral antidiabetic drug (OAD)–treated control group. Methods: This prospective, observational study included 100 patients with type 2 diabetes: an insulin group (n = 55; basal insulin added to OADs) and an OAD control group (n = 45). Psychological distress was assessed at baseline and 6 months using the Hospital Anxiety and Depression Scale (HADS) alongside HbA1c monitoring. Trajectories were analyzed using 2×2 repeated-measures ANOVA, and within-group changes via paired t tests. Standardized effect sizes (Cohen d) were calculated at 6 months. Results: At baseline, diabetes duration and HbA1c levels were higher in the insulin group, while anxiety scores were higher in the OAD group (P < .001 for all). At 6 months, mean (SD) HbA1c decreased significantly in the insulin group (from 9.51% [0.72%] to 7.49% [0.78%]; P < .001) but remained stable in the OAD group. Repeated-measures ANOVA showed significant time × group interactions for anxiety (F 1,98 = 69.16; P < .001) and depression (F 1,98 = 85.68; P < .001). Within the insulin group, mean (SD) scores increased significantly for anxiety (from 6.98 [2.00] to 11.25 [2.74]; P < .001) and depression (from 8.25 [2.05] to 12.36 [2.26]; P < .001). At 6 months, between-group differences reflected substantial clinical magnitudes favoring the control group for both anxiety (Cohen d = 1.14) and depression (Cohen d = 2.29). Conclusions: Insulin initiation was associated with increased anxiety and depression symptoms over 6 months despite improved glycemic control. These findings underscore the need to integrate structured psychosocial support into clinical care during insulin transition.