Effect of Interpersonal Therapy on Perceived Social Support and Depressive Symptoms in Adults With Type 2 Diabetes: A Randomized Controlled Trial Publisher



Sadeghi F ; Bahrami M ; Lord B ; Kaviani M ; Mousavizadeh SN
Source: Journal of Nursing and Midwifery Sciences Published:2025

Abstract

Background: Type 2 diabetes mellitus (T2DM) imposes a significant psychological burden, with depression and limited social support prevalent among patients, adversely affecting self-care and quality of life. This study evaluated the efficacy of interpersonal therapy (IPT), a structured psychotherapy targeting interpersonal stressors, in improving depressive symptoms and perceived social support in T2DM adults. Objectives: The present randomized controlled trial (RCT) aimed to determine the efficacy of IPT in improving perceived social support and depressive symptoms among adults with type 2 diabetes. By doing so, the study seeks to contribute to a more holistic understanding of diabetes care and offer practical implications for integrating psychotherapeutic approaches into chronic disease management. Methods: In a RCT conducted in Tehran, Iran, in 2025, 110 adults aged 18-65 with T2DM and mild-to-severe depressive symptoms [Beck Depression Inventory-II (BDI-II) ≥ 14] were assigned to receive 10 weekly IPT sessions or standard care using simple randomization. Certified therapists delivered IPT, focusing on interpersonal stressors such as role disputes and transitions. Outcomes were measured using the Multidimensional Scale of Perceived Social Support (MSPSS) and BDI-II at baseline (T0), post-intervention (T1), and two-month follow-up (T2). Data were analyzed using repeated-measures analysis of variance (ANOVA) and linear mixed-effects models (LMMs), with intention-to-treat (ITT) analysis addressing a 5.45% attrition rate; gender and marital status were explored as moderators. Results: The intervention group (n = 51) significantly improved MSPSS scores from T0 to T1 (P < 0.001) and T2 (P = 0.002), while BDI-II scores decreased from T0 to T1 (P < 0.001) and T2 (P < 0.001). The control group (n = 53) showed declining MSPSS scores from T0 to T1 (P = 0.017) and T0 to T2 (P = 0.013), with minimal BDI-II change (P = 0.614). Significant time-by-group interactions were observed for MSPSS (P < 0.001) and BDI-II (P < 0.001), with between-group Cohen’s d = 0.63-1.08. Females and married participants showed greater improvements in both outcomes (P = 0.031 for MSPSS, P = 0.021 for BDI-II). The LMMs confirmed these findings, and no baseline group differences existed (P > 0.05). Conclusions: The IPT significantly enhanced perceived social support and reduced depressive symptoms in T2DM adults, with sustained effects at T2, particularly for females and married individuals. These findings support integrating IPT into T2DM care to address psychosocial challenges, with future research needed to explore physiological impacts and long-term outcomes. © 2025 Elsevier B.V., All rights reserved.