Loneliness Predicts Symptom Outcomes Following a Digital Intervention for Appearance Concerns

Digital mental health interventions have proliferated in the past decade, though it is not clear whether social isolation or loneliness influences their efficacy. The present study sought to determine whether loneliness predicted symptom outcomes following a digital treatment for appearance concerns. Women elevated in appearance concerns (N = 203) were randomized to one of two interventions where participants were either instructed to reduce appearance-related safety behaviors (ARSB; i.e., actions people take to reduce appearance anxiety) or general unhealthy behaviors. Both treatments led to similar reductions in loneliness. However, we found that baseline loneliness moderated the effect of condition on social anxiety such that, at low levels of loneliness, ARSB reduction led to lower social anxiety than control, though these effects were absent at high levels of loneliness. We also found that, in the ARSB treatment condition (but not the control condition), pretreatment loneliness predicted symptoms of social anxiety at posttreatment and predicted social anxiety, eating disorder symptoms, and depression at follow-up. Taken together, loneliness appears to play an important role in the efficacy of this digital intervention, findings which may have implications for the broader digital treatment literature.