Introduction: Type 2 diabetes mellitus (T2DM) is a chronic condition with significant psychological and physiological burdens, including diabetes distress and poor glycemic control. Interpersonal Therapy (IPT) addresses interpersonal challenges that may exacerbate distress and hinder self-management. This study evaluates IPT's efficacy in reducing diabetes distress, enhancing self-efficacy, and improving glycemic control in adults with T2DM compared to standard care.
Methods: This randomized controlled trial enrolled 136 adults with T2DM, randomized 1:1 to receive either 12 weekly 60-minute IPT sessions or four biweekly 90-minute standard diabetes education sessions. IPT focused on role transitions, interpersonal disputes, grief, and deficits, delivered in small groups by trained psychologists. The control group received education on diet, exercise, and medication adherence. Outcomes, assessed at baseline, post-intervention (12 weeks), and 2-month follow-up, included Diabetes Distress Scale (DDS), Diabetes Management Self-Efficacy Scale (DMSES), and laboratory markers (HbA1c, fasting blood glucose [FBG], lipids). Data were analyzed using linear mixed-effects models, with p < 0.05 indicating significance.
Results: Of 136 participants, 128 completed the study (IPT: n = 63; control: n = 65). Baseline characteristics were comparable (mean age: 52.4 ± 8.7 years IPT; 53.1 ± 9.2 years control). IPT significantly reduced DDS scores post-intervention (p = 0.02, Cohen's d = 0.48) and at follow-up (p = 0.01, Cohen's d = 0.57) compared to control. Self-efficacy (DMSES) improved more in IPT post-intervention (p = 0.001, Cohen's d = 0.71), though differences were non-significant at follow-up (p = 0.09). IPT showed greater improvements in HbA1c (p = 0.01 post-intervention, Cohen's d = 0.44; p = 0.02 follow-up, Cohen's d = 0.47), FBG (p = 0.03 post-intervention, Cohen's d = 0.46; p = 0.02 follow-up, Cohen's d = 0.50), and HDL (p = 0.02 post-intervention, Cohen's d = 0.43; p = 0.01 follow-up, Cohen's d = 0.47). Control group improved in total cholesterol (p = 0.03) and triglycerides (p = 0.04). No significant between-group differences were found for LDL.
Conclusion: IPT significantly reduced diabetes distress, enhanced self-efficacy, and improved HbA1c, FBG, and HDL compared to standard education in T2DM patients. Standard education improved lipid profiles, suggesting complementary benefits. Integrating IPT into diabetes care could enhance psychological and metabolic outcomes.
Supplementary information: The online version contains supplementary material available at 10.1007/s40200-026-01907-6.
Keywords: Diabetes distress; Fasting blood glucose; Glycemic control; Hemoglobin A1c; Interpersonal psychotherapy; Lipid metabolism; Psychological intervention; Randomized controlled trial; Self-Efficacy; Type 2 diabetes mellitus.
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