Mental health interventions for carers of individuals with eating disorders: a systematic review of randomized controlled trials assessing efficacy on anxiety and depressive symptoms

Background: Carers of individuals with eating disorders (EDs) often experience high levels of psychological distress, which can lead to anxiety and depressive symptoms. While several interventions have been developed to support carers, the effectiveness on their mental health remains unclear. Methods: We performed a systematic review of randomized controlled trials (RCTs) assessing mental health interventions for carers of individuals with EDs, with anxiety and depressive symptoms defined as outcomes of interest. Searches were performed across major electronic databases up to 31 October 2025. Results: Twelve RCTs met the inclusion criteria. Structured narrative synthesis indicated that statistically significant effects were infrequent, outcome-specific, and generally small in magnitude. Interventions based on the Cognitive-Interpersonal Maintenance Model (CIMM) were the most frequently evaluated. However, only one trial demonstrated significant improvements in depressive symptoms (p = 0.010), with no significant effect on the Depression Anxiety Stress Scale (DASS-21) total scores (p = 0.06) or on the anxiety subscale (p = 0.50). In addition, Cognitive Behavioural Therapy (CBT)-based interventions showed some promising effects on the Hospital Anxiety and Depression Scale (HADS) total score (p = 0.033), but these results were not consistently replicated across guided and unguided formats. Among the other approaches, a video-based skills-training intervention produced a measurable reduction in carer distress, but this effect was observed only when combined with professional support (p = 0.030). Overall, interventions incorporating professional or peer support appeared more promising than fully self-directed approaches, although direct comparisons between guided and unguided formats did not consistently show statistically significant differences. Quality assessment showed at least an average standard of quality for all the included trials. Conclusions: Interventions for carers of individuals with EDs are conceptually well-founded, yet current evidence provides only limited support for their effectiveness in reducing anxiety and depressive symptoms. Future research should prioritize interventions that combine more structured mental health strategies with guided self-help programmes and workshops, providing tailored support to address the various needs of carers.