Abstract
Social interactions play a central role in regulating affect and physiological arousal, with familiar and supportive relationships often associated with reduced anxiety and adaptive autonomic responses. However, it remains unclear whether individuals with depression benefit similarly from these so-called social buffering effects in everyday life. The present study examined momentary anxiety and cardiovascular responses (heart rate [HR] and heart rate variability [HRV]) during real-life social interactions in patients suffering from depression (N = 57) and matched healthy controls (N = 57). Participants reported on the familiarity and the gender of social interaction partners and the interaction context across five days, while a subsample also wore ambulatory electrocardiogram sensors. Across the patient and control group, higher interaction partner familiarity was associated with reduced state anxiety. However, only controls reported lower social interaction anxiety with increasing familiarity, whereas this pattern was not observed in patients. State social interaction anxiety was higher in controls when they interacted with female interaction partners, while there were no differences for patients. Regarding autonomic responses, patients exhibited higher baseline and state HR and lower baseline and state HRV compared to controls, consistent with autonomic dysregulation. We also observed lower HRs in opposite-gender interactions among controls but not among patients. Overall, these findings suggest that familiar social interactions are associated with lower levels of general state anxiety in both patients with depression and healthy controls, whereas social interaction anxiety and autonomic responses appear to show weaker associations with familiarity or the gender of interaction partners in patients. This research offers insights into how everyday social environments might support emotion regulation in clinical populations.