Interoception mediates the association between social support and sociability in patients with major depressive disorder.

Background: Interoception dysfunction has an important impact on the onset and development of major depressive disorder (MDD). Social support serves as a protective factor against MDD, and sociability also plays a significant role in this condition. These interconnected constructs-social support and sociability-play pivotal roles in MDD. However, no research on the mechanisms underlying the associations between social support and sociability, particularly the potential role of interoception, have been reported.

Aim: To investigate the mediating effect of interoception between social support and social ability and to explore the independent role of social support in sociability.

Methods: The participants included 292 patients with MDD and 257 healthy controls (HCs). The patient health questionnaire 9, the multidimensional assessment of interoception awareness, version 2 (MAIA-2), the social support rating scale (SSRS), and the Texas social behavior inventory (TSBI) were used to assess depression, interoception, social support, and sociability, respectively. A mediation analysis model for the eight dimensions of interoception (noticing, not distracting, not worrying, attention regulation, emotional awareness, self-regulation, body listening, and trust), social support, and sociability were established to evaluate the mediating effects.

Results: A partial correlation analysis of eight dimensions of the MAIA-2, SSRS, and TSBI scores, with demographic data as control variables, revealed pairwise correlations between the SSRS score and both the MAIA-2 score and TSBI score. In the major depression (MD) group, the SSRS score had a positive direct effect on the TSBI score, while the scores for body listening, emotional awareness, self-regulation, and trust in the MAIA-2C had indirect effects on the TSBI score. In the HC group, the SSRS score had a positive direct effect on the TSBI score, and the scores for attention regulation, emotional awareness, self-regulation, and trust in the MAIA-2C had indirect effects on the TSBI score. The proportion of mediators in the MD group was lower than that in the HC group.

Conclusion: Interoceptive awareness is a mediating factor in the association between social support and sociability in both HCs and depressed patients. Training in interoceptive awareness might not only help improve emotional regulation in depressed patients but also enhance their social skills and support networks.